Network Working Group                                      T. Morin, Ed.
Request for Comments: 4834                            France Telecom R&D
Category: Informational                                       April 2007

Requirements for Multicast in Layer 3 Provider-Provisioned Virtual Private Networks (PPVPNs)


Status of This Memo


This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited.


Copyright Notice


Copyright (C) The IETF Trust (2007).




This document presents a set of functional requirements for network solutions that allow the deployment of IP multicast within Layer 3 (L3) Provider-Provisioned Virtual Private Networks (PPVPNs). It specifies requirements both from the end user and service provider standpoints. It is intended that potential solutions specifying the support of IP multicast within such VPNs will use these requirements as guidelines.


Table of Contents


   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Conventions Used in This Document  . . . . . . . . . . . . . .  5
     2.1.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  5
     2.2.  Conventions  . . . . . . . . . . . . . . . . . . . . . . .  6
   3.  Problem Statement  . . . . . . . . . . . . . . . . . . . . . .  7
     3.1.  Motivations  . . . . . . . . . . . . . . . . . . . . . . .  7
     3.2.  General Requirements . . . . . . . . . . . . . . . . . . .  7
     3.3.  Scaling vs. Optimizing Resource Utilization  . . . . . . .  8
   4.  Use Cases  . . . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.1.  Scenarios  . . . . . . . . . . . . . . . . . . . . . . . .  8
       4.1.1.  Live Content Broadcast . . . . . . . . . . . . . . . .  9
       4.1.2.  Symmetric Applications . . . . . . . . . . . . . . . . 10
       4.1.3.  Data Distribution  . . . . . . . . . . . . . . . . . . 10
       4.1.4.  Generic Multicast VPN Offer  . . . . . . . . . . . . . 11
     4.2.  Scalability Orders of Magnitude  . . . . . . . . . . . . . 11
       4.2.1.  Number of VPNs with Multicast Enabled  . . . . . . . . 11
       4.2.2.  Number of Multicast VPNs per PE  . . . . . . . . . . . 12
       4.2.3.  Number of CEs per Multicast VPN per PE . . . . . . . . 12
       4.2.4.  PEs per Multicast VPN  . . . . . . . . . . . . . . . . 12
       4.2.5.  PEs with Multicast VRFs  . . . . . . . . . . . . . . . 13
       4.2.6.  Number of Streams Sourced  . . . . . . . . . . . . . . 13
   5.  Requirements for Supporting IP Multicast within L3 PPVPNs  . . 13
     5.1.  End User/Customer Standpoint . . . . . . . . . . . . . . . 13
       5.1.1.  Service Definition . . . . . . . . . . . . . . . . . . 13
       5.1.2.  CE-PE Multicast Routing and Group Management
               Protocols  . . . . . . . . . . . . . . . . . . . . . . 14
       5.1.3.  Quality of Service (QoS) . . . . . . . . . . . . . . . 14
       5.1.4.  Operations and Management  . . . . . . . . . . . . . . 15
       5.1.5.  Security Requirements  . . . . . . . . . . . . . . . . 16
       5.1.6.  Extranet . . . . . . . . . . . . . . . . . . . . . . . 17
       5.1.7.  Internet Multicast . . . . . . . . . . . . . . . . . . 18
       5.1.8.  Carrier's Carrier  . . . . . . . . . . . . . . . . . . 18
       5.1.9.  Multi-Homing, Load Balancing, and Resiliency . . . . . 19
       5.1.10. RP Engineering . . . . . . . . . . . . . . . . . . . . 19
       5.1.11. Addressing . . . . . . . . . . . . . . . . . . . . . . 20
       5.1.12. Minimum MTU  . . . . . . . . . . . . . . . . . . . . . 20
     5.2.  Service Provider Standpoint  . . . . . . . . . . . . . . . 21
       5.2.1.  General Requirement  . . . . . . . . . . . . . . . . . 21
       5.2.2.  Scalability  . . . . . . . . . . . . . . . . . . . . . 21
       5.2.3.  Resource Optimization  . . . . . . . . . . . . . . . . 23
       5.2.4.  Tunneling Requirements . . . . . . . . . . . . . . . . 24
       5.2.5.  Control Mechanisms . . . . . . . . . . . . . . . . . . 26
       5.2.6.  Support of Inter-AS, Inter-Provider Deployments  . . . 26
       5.2.7.  Quality-of-Service Differentiation . . . . . . . . . . 27
       5.2.8.  Infrastructure security  . . . . . . . . . . . . . . . 27
       5.2.9.  Robustness . . . . . . . . . . . . . . . . . . . . . . 28
       5.2.10. Operation, Administration, and Maintenance . . . . . . 28
       5.2.11. Compatibility and Migration Issues . . . . . . . . . . 29
       5.2.12. Troubleshooting  . . . . . . . . . . . . . . . . . . . 30
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 30
   7.  Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 31
   8.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 31
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 32
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 32
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 33
1. Introduction
1. はじめに

Virtual Private Network (VPN) services satisfying the requirements defined in [RFC4031] are now being offered by many service providers throughout the world. VPN services are popular because customers need not be aware of the VPN technologies deployed in the provider network. They scale well for the following reasons:


o because P routers (Provider Routers) need not be aware of VPN service details

O Pルータ(プロバイダールータ)がVPNサービスの詳細を意識する必要がないので、

o because the addition of a new VPN member requires only limited configuration effort


There is also a growing need for support of IP multicast-based services. Efforts to provide efficient IP multicast routing protocols and multicast group management have been made in standardization bodies which has led, in particular, to the definition of Protocol Independent Multicast (PIM) and Internet Group Management Protocol (IGMP).

IPマルチキャストベースのサービスをサポートするためのニーズの高まりもあります。効率的なIPマルチキャストルーティングプロトコルおよびマルチキャストグループ管理を提供するための努力は、Protocol Independent Multicast(PIM)とインターネットグループ管理プロトコル(IGMP)の定義に、特に、つながっている標準化機関で行われています。

However, multicast traffic is not natively supported within existing L3 PPVPN solutions. Deploying multicast over an L3VPN today, with only currently standardized solutions, requires designing customized solutions which will be inherently limited in terms of scalability, operational efficiency, and bandwidth usage.

しかし、マルチキャストトラフィックはネイティブに、既存のL3 PPVPNソリューション内でサポートされていません。唯一、現在標準化されたソリューションとL3VPNの上にマルチキャスト今日、展開、本質的に拡張性、運用効率、および帯域幅の使用に関して制限されるカスタマイズされたソリューションを設計する必要があり。

This document complements the generic L3VPN requirements [RFC4031] document, by specifying additional requirements specific to the deployment within PPVPNs of services based on IP multicast. It clarifies the needs of both VPN clients and providers and formulates the problems that should be addressed by technical solutions with the key objective being to remain solution agnostic. There is no intent in this document to specify either solution-specific details or application-specific requirements. Also, this document does NOT aim at expressing multicast-related requirements that are not specific to L3 PPVPNs.

この文書では、IPマルチキャストに基づいてサービスのPPVPNs内の展開に特有の追加要件を指定することで、一般的なL3VPN要件[RFC4031]文書を補完します。これは、VPNクライアントとプロバイダーの両方のニーズを明確にし、主要な目的は、ソリューションにとらわれないままにすることで技術的な解決策で対処すべき問題を定式化します。ソリューション固有の詳細情報や、アプリケーション固有の要件のいずれかを指定するには、この文書の意図はありません。また、この文書は、L3 PPVPNsに固有のものではありませんマルチキャスト関連の要件を表現することを目指しません。

It is expected that solutions that specify procedures and protocol extensions for multicast in L3 PPVPNs SHOULD satisfy these requirements.

L3 PPVPNsにおけるマルチキャストのための手順やプロトコル拡張を指定するソリューションは、これらの要件を満たすべきであることが期待されます。

2. Conventions Used in This Document
2.1. Terminology
2.1. 用語

Although the reader is assumed to be familiar with the terminology defined in [RFC4031], [RFC4364], [RFC4601], and [RFC4607], the following glossary of terms may be worthwhile.


We also propose here generic terms for concepts that naturally appear when multicast in VPNs is discussed.


ASM: Any Source Multicast. One of the two multicast service models, in which a terminal subscribes to a multicast group to receive data sent to the group by any source.


Multicast-enabled VPN, multicast VPN, or mVPN: A VPN that supports IP multicast capabilities, i.e., for which some PE devices (if not all) are multicast-enabled and whose core architecture supports multicast VPN routing and forwarding.


PPVPN: Provider-Provisioned Virtual Private Network.


PE, CE: "Provider Edge", "Customer Edge" (as defined in [RFC4026]). As suggested in [RFC4026], we will use these notations to refer to the equipments/routers/devices themselves. Thus, "PE" will refer to the router on the provider's edge, which faces the "CE", the router on the customer's edge.

PE、CE: "プロバイダエッジ"、 "顧客エッジ"([RFC4026]で定義されるように)。 [RFC4026]で示唆したように、我々は機器/ルータ/デバイス自体を参照するためにこれらの表記を使用します。したがって、「PE」「CE」、顧客のエッジ上のルータと対向プロバイダのエッジ上のルータを参照します。

VRF or VR: By these terms, we refer to the entity defined in a PE dedicated to a specific VPN instance. "VRF" refers to "VPN Routing and Forwarding table" as defined in [RFC4364], and "VR" to "Virtual Router" as defined in [VRs] terminology.

VRFかVRは:これらの用語によって、我々は特定のVPNインスタンスに専用のPEに定義されたエンティティを参照してください。 「VRF」は、[仮想ルーター]用語で定義される「仮想ルータ」に[RFC4364]で定義されるように、「VPNルーティングおよび転送テーブル」を参照し、「VR」。

MDTunnel: Multicast Distribution Tunnel. The means by which the customer's multicast traffic will be transported across the SP network. This is meant in a generic way: such tunnels can be either point-to-point or point-to-multipoint. Although this definition may seem to assume that distribution tunnels are unidirectional, the wording also encompasses bidirectional tunnels.


S: Denotes a multicast source.


G: Denotes a multicast group.


Multicast channel: In the multicast SSM model [RFC4607], a "multicast channel" designates traffic from a specific source S to a multicast group G. Also denominated as "(S,G)".


SP: Service provider.


SSM: Source Specific Multicast. One of the two multicast service models, where a terminal subscribes to a multicast group to receive data sent to the group by a specific source.


RP: Rendezvous Point (Protocol Independent Multicast - Sparse Mode (PIM-SM) [RFC4601]).

RP:ランデブーポイント(プロトコル独立マルチキャスト - スパースモード(PIM-SM)[RFC4601])。

P2MP, MP2MP: Designate "Point-to-Multipoint" and "Multipoint-to-Multipoint" replication trees.


L3VPN, VPN: Throughout this document, "L3VPN" or even just "VPN" will refer to "Provider-Provisioned Layer 3 Virtual Private Network" (PP L3VPNs), and will be preferred for readability.

L3VPN、VPN:このドキュメントでは、「L3VPN」あるいは単に「VPN」は、「プロバイダ・プロビジョニングのレイヤ3仮想プライベートネットワーク」(PP L3VPNs)を参照し、読みやすくするために好ましいであろう。

Please refer to [RFC4026] for details about terminology specifically relevant to VPN aspects, and to [RFC2432] for multicast performance or quality of service (QoS)-related terms.

用語 - 関連マルチキャスト性能やサービス品質(QoS)のために特にVPNの側面に関連して、[RFC2432]への用語の詳細については、[RFC4026]を参照してください。

2.2. Conventions
2.2. 表記

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].

この文書のキーワード "MUST"、 "MUST NOT"、 "REQUIRED"、、、、 "べきではない" "べきである" "ないもの" "ものとし"、 "推奨"、 "MAY"、および "OPTIONAL" はあります[RFC2119]に記載されているように解釈されます。

3. Problem Statement
3.1. Motivations
3.1. 動機

More and more L3VPN customers use IP multicast services within their private infrastructures. Naturally, they want to extend these multicast services to remote sites that are connected via a VPN.


For instance, the customer could be a national TV channel with several geographical locations that wants to broadcast a TV program from a central point to several regional locations within its VPN.


A solution to support multicast traffic could consist of point-to-point tunnels across the provider network and requires the PEs (Provider Edge routers) to replicate traffic. This would obviously be sub-optimal as it would place the replication burden on the PE and hence would have very poor scaling characteristics. It would also probably waste bandwidth and control plane resources in the provider's network.


Thus, to provide multicast services for L3VPN networks in an efficient manner (that is, with a scalable impact on signaling and protocol state as well as bandwidth usage), in a large-scale environment, new mechanisms are required to enhance existing L3VPN solutions for proper support of multicast-based services.


3.2. General Requirements
3.2. 一般要件

This document sets out requirements for L3 provider-provisioned VPN solutions designed to carry customers' multicast traffic. The main requirement is that a solution SHOULD first satisfy the requirements documented in [RFC4031]: as far as possible, a multicast service should have the same characteristics as the unicast equivalent, including the same simplicity (technology unaware), the same quality of service (if any), the same management (e.g., performance monitoring), etc.


Moreover, it also has to be clear that a multicast VPN solution MUST interoperate seamlessly with current unicast VPN solutions. It would also make sense that multicast VPN solutions define themselves as extensions to existing L3 provider-provisioned VPN solutions (such as for instance, [RFC4364] or [VRs]) and retain consistency with those, although this is not a core requirement.


The requirements in this document are equally applicable to IPv4 and IPv6, for both customer- and provider-related matters.


3.3. Scaling vs. Optimizing Resource Utilization
3.3. 最適化リソース使用率対スケーリング

When transporting multicast VPN traffic over a service provider network, there intrinsically is tension between scalability and resource optimization, since the latter is likely to require the maintenance of control plane states related to replication trees in the core network [RFC3353].


Consequently, any deployment will require a trade-off to be made. This document will express some requirements related to this trade-off.


4. Use Cases

The goal of this section is to highlight how different applications and network contexts may have a different impact on how a multicast VPN solution is designed, deployed, and tuned. For this purpose, we describe some typical use case scenarios and express expectations in terms of deployment orders of magnitude.


Most of the content of these sections originates from a survey done in summer 2005, among institutions and providers that expect to deploy such solutions. The full survey text and raw results (13 responses) were published separately, and we only present here the most relevant facts and expectations that the survey exposed.


For scalability figures, we considered that it was relevant to highlight the highest expectations, those that are expected to have the greatest impact on solution design. For balance, we do also mention cases where such high expectations were expressed in only a few answers.


4.1. Scenarios
4.1. シナリオ

We don't provide here an exhaustive set of scenarios that a multicast VPN solution is expected to support -- no solution should restrict the scope of multicast applications and deployments that can be done over a multicast VPN.

何の解決策は、マルチキャストVPNを介して行うことができマルチキャストアプリケーションと展開の範囲を制限するべきではない - 私たちはここで、マルチキャストVPNソリューションをサポートすることが期待されているシナリオの網羅セットを提供していません。

Hence, we only give here a short list of scenarios that are expected to have a large impact on the design of a multicast VPN solution.


4.1.1. Live Content Broadcast
4.1.1. ライブコンテンツのブロードキャスト

Under this label, we group all applications that distribute content (audio, video, or other content) with the property that this content is expected to be consulted at once ("live") by the receiver. Typical applications are broadcast TV, production studio connectivity, and distribution of market data feeds.


The characteristics of such applications are the following:


o one or few sources to many receivers


o sources are often in known locations; receivers are in less predictable locations (this latter point may depend on applications)


o in some cases, it is expected that the regularity of audience patterns may help improve how the bandwidth/state trade-off is handled


o the number of streams can be as high as hundreds, or even thousands, of streams


o bandwidth will depend on the application, but may vary between a few tens/hundreds of Kb/s (e.g., audio or low-quality video media) and tens of Mb/s (high-quality video), with some demanding professional applications requiring as much as hundreds of Mb/s.

O帯域幅は、アプリケーションに依存しますが、KB /秒の数十/数百(例えば、オーディオまたは低品質のビデオメディア)との間で数十メガビット/秒(高品質のビデオ)の異なる場合があり、いくつかの厳しいプロフェッショナルアプリケーションとMb /秒の何百もの限りを必要とします。

o QoS requirements include, in many cases, a low multicast group join delay


o QoS of these applications is likely to be impacted by packet loss (some applications may be robust to low packet loss) and to have low robustness against jitter


o delay sensitivity will depend on the application: some applications are not so delay sensitive (e.g., broadcast TV), whereas others may require very low delay (professional studio applications)


o some of these applications may involve rapid changes in customer multicast memberships as seen by the PE, but this will depend on audience patterns and on the amount of provider equipments deployed close to VPN customers

O PEで見られるように、これらのアプリケーションのいくつかは、顧客のマルチキャストメンバーシップの急激な変化を伴うことが、これは観客のパターンに近いとVPNの顧客に展開され、プロバイダの機器の量に依存します

4.1.2. Symmetric Applications
4.1.2. 対称型アプリケーション

Some use cases exposed by the survey can be grouped under this label, and include many-to-many applications such as conferencing and server cluster monitoring.


They are characterized by the relatively high number of streams that they can produce, which has a direct impact on scalability expectations.


A sub-case of this scenario is the case of symmetric applications with small groups, when the number of receivers is low compared to the number of sites in the VPNs (e.g., video conferencing and e-learning applications).


This latter case is expected to be an important input to solution design, since it may significantly impact how the bandwidth/state is managed.


Optimizing bandwidth may require introducing dedicated states in the core network (typically as much as the number of groups) for the following reasons:


o small groups, and low predictability of the location of participants ("sparse groups")


o possibly significantly high bandwidth (a few Mb/s per participant)

Oおそらく非常に高い帯域幅(数MB / sの参加者あたり)

Lastly, some of these applications may involve real-time interactions and will be highly sensitive to packet loss, jitter, and delay.


4.1.3. Data Distribution
4.1.3. データ配信

Some applications that are expected to be deployed on multicast VPNs are non-real-time applications aimed at distributing data from few sources to many receivers.


Such applications may be considered to have lower expectations than their counterparts proposed in this document, since they would not necessarily involve more data streams and are more likely to adapt to the available bandwidth and to be robust to packet loss, jitter, and delay.


One important property is that such applications may involve higher bandwidths (hundreds of Mb/s).

1つの重要な特性は、そのようなアプリケーションは、より高い帯域幅(数百MB / s)を伴うことです。

4.1.4. Generic Multicast VPN Offer
4.1.4. 一般的なマルチキャストVPNオファー

This ISP scenario is a deployment scenario where IP-multicast connectivity is proposed for every VPN: if a customer requests a VPN, then this VPN will support IP multicast by default. In this case, the number of multicast VPNs equals the number of VPNs. This implies a quite important scalability requirement (e.g., hundreds of PEs, hundreds of VPNs per PE, with a potential increase by one order of magnitude in the future).


The per-mVPN traffic behavior is not predictable because how the service is used is completely up to the customer. This results in a traffic mix of the scenarios mentioned in Section 4.1. QoS requirements are similar to typical unicast scenarios, with the need for different classes. Also, in such a context, a reasonably large range of protocols should be made available to the customer for use at the PE-CE level.

サービスがどのように使われるか、完全にお客様次第ですのでごとのMVPNトラフィックの動作は予測できません。これは、4.1節で述べたシナリオのトラフィックミックスになります。 QoS要件は、異なるクラスの必要性と、典型的なユニキャストのシナリオに似ています。また、このような状況において、プロトコルの合理的に広い範囲は、PE-CEレベルでの使用のために顧客に利用可能にされるべきです。

Also, in such a scenario, customers may want to deploy multicast connectivity between two or more multicast VPNs as well as access to Internet Multicast.


4.2. Scalability Orders of Magnitude
4.2. マグニチュードのスケーラビリティ受注

This section proposes orders of magnitude for different scalability metrics relevant for multicast VPN issues. It should be noted that the scalability figures proposed here relate to scalability expectations of future deployments of multicast VPN solutions, as the authors chose to not restrict the scope to only currently known deployments.


4.2.1. Number of VPNs with Multicast Enabled
4.2.1. マルチキャストでのVPNの数が有効

From the survey results, we see a broad range of expectations. There are extreme answers: from 5 VPNs (1 answer) to 10k VPNs (1 answer), but more typical answers are split between the low range of tens of VPNs (7 answers) and the higher range of hundreds or thousands of VPNs (2 + 4 answers).

調査結果から、我々は期待の広い範囲を参照してください。 2(5つのVPNの(1答)から10KのVPN(1答)に、より多くの一般的な答えは、VPNの(7つの解答)の数十の低域の間で分割され、VPNの数百または数千の高い範囲:あり、極端な答えがあります+ 4件の回答)。

A solution SHOULD support a number of multicast VPNs ranging from one to several thousands.


A solution SHOULD NOT limit the proportion of multicast VPNs among all (unicast) VPNs.


4.2.2. Number of Multicast VPNs per PE
4.2.2. PEあたりのマルチキャストVPNの数

The majority of survey answers express a number of multicast VPNs per PE of around tens (8 responses between 5 and 50); a significant number of them (4) expect deployments with hundreds or thousands (1 response) of multicast VPNs per PE.


A solution SHOULD support a number of multicast VPNs per PE of several hundreds, and may have to scale up to thousands of VPNs per PE.


4.2.3. Number of CEs per Multicast VPN per PE
4.2.3. PEあたりのマルチキャストVPNあたりのCEの数

Survey responses span from 1 to 2000 CEs per multicast VPN per PE. Most typical responses are between tens (6 answers) and hundreds (4 responses).

アンケートの回答は、1からPEあたりのマルチキャストVPNあたり2000 CEにまたがります。最も典型的な応答は、十(6件の回答可)と数百人(4件の回答)の間にあります。

A solution SHOULD support a number of CEs per multicast VPN per PE going up to several hundreds (and may target the support of thousands of CEs).


4.2.4. PEs per Multicast VPN
4.2.4. マルチキャストVPNあたりのPE

People who answered the survey typically expect deployments with the number of PEs per multicast VPN in the range of hundreds of PEs (6 responses) or tens of PEs (4 responses). Two responses were in the range of thousands (one mentioned a 10k figure).

アンケートに答え人々は、通常のPE(6件の回答)または十PEの(4つの応答)の数百の範囲のマルチキャストVPNあたりのPEの数と展開を期待しています。 2つの応答は、(1が10Kの図を述べた)何千人もの範囲でした。

A multicast VPN solution SHOULD support several hundreds of PEs per multicast VPN, and MAY usefully scale up to thousands.

マルチキャストVPNソリューションは、マルチキャストVPNあたりのPEの数百をサポートする必要があり、有効に数千人にスケールアップするかもしれません。 ... with Sources。 ...ソースを使用します

The number of PEs (per VPN) that would be connected to sources seems to be significantly lower than the number of PEs per VPN. This is obviously related to the fact that many respondents mentioned deployments related to content broadcast applications (one to many).


Typical numbers are tens (6 responses) or hundreds (4 responses) of source-connected PEs. One respondent expected a higher number of several thousands.


A solution SHOULD support hundreds of source-connected PEs per VPN, and some deployment scenarios involving many-to-many applications may require supporting a number of source-connected PEs equal to the number of PEs (hundreds or thousands).

溶液は、VPN当たりソースに接続されたPEの数百、及びPES(数百または数千)の数に等しいソースに接続されたPEの数をサポートする必要な場合があり、多対多の用途を含むいくつかの展開シナリオをサポートしなければなりません。 ... with Receivers。 ...レシーバ付き

The survey showed that the number of PEs with receivers is expected to be of the same order of magnitude as the number of PEs in a multicast VPN. This is consistent with the intrinsic nature of most multicast applications, which have few source-only participants.


4.2.5. PEs with Multicast VRFs
4.2.5. マルチキャストVRFを使用するPE

A solution SHOULD scale up to thousands of PEs having multicast service enabled.


4.2.6. Number of Streams Sourced
4.2.6. ストリームソース化の数

Survey responses led us to retain the following orders of magnitude for the number of streams that a solution SHOULD support:


per VPN: hundreds or thousands of streams


per PE: hundreds of streams


5. Requirements for Supporting IP Multicast within L3 PPVPNs
L3 PPVPNs内IPマルチキャストをサポートするための要件5.

Again, the aim of this document is not to specify solutions but to give requirements for supporting IP multicast within L3 PPVPNs.

ここでも、この文書の目的は、解決策を指定するのではなく、L3 PPVPNs内のIPマルチキャストをサポートするための要件を与えることはありません。

In order to list these requirements, we have taken the standpoint of two different important entities: the end user (the customer using the VPN) and the service provider.


In the rest of the document, by "a solution" or "a multicast VPN solution", we mean a solution that allows multicast in an L3 provider-provisioned VPN, and which addresses the requirements listed in this document.


5.1. End User/Customer Standpoint
5.1. エンドユーザー/顧客視点
5.1.1. Service Definition
5.1.1. サービスの定義

As for unicast, the multicast service MUST be provider provisioned and SHALL NOT require customer devices (CEs) to support any extra features compared to those required for multicast in a non-VPN context. Enabling a VPN for multicast support SHOULD be possible with no impact (or very limited impact) on existing multicast protocols possibly already deployed on the CE devices.


5.1.2. CE-PE Multicast Routing and Group Management Protocols
5.1.2. CE-PEマルチキャストルーティングおよびグループ管理プロトコル

Consequently to Section 5.1.1, multicast-related protocol exchanges between a CE and its directly connected PE SHOULD happen via existing multicast protocols.


Such protocols include: PIM-SM [RFC4601], bidirectional-PIM [BIDIR-PIM], PIM - Dense Mode (DM) [RFC3973], and IGMPv3 [RFC3376] (this version implicitly supports hosts that only implement IGMPv1 [RFC1112] or IGMPv2 [RFC2236]).

そのようなプロトコルは:PIM-SM [RFC4601]、双方向PIM [BIDIR-PIM]、PIM - 稠密モード(DM)[RFC3973]、およびIGMPv3 [RFC3376](このバージョンは暗黙のみのIGMPv1 [RFC1112]を実装するホストをサポートするかをIGMPv2の[RFC2236])。

Among those protocols, the support of PIM-SM (which includes the SSM model) and either IGMPv3 (for IPv4 solutions) and/or Multicast Listener Discovery Version 2 (MLDv2) [RFC3810] (for IPv6 solutions) is REQUIRED. Bidir-PIM support at the PE-CE interface is RECOMMENDED. And considering deployments, PIM-DM is considered OPTIONAL.

これらのプロトコルのうち、(SSMモデルを含む)PIM-SMおよび(IPv4のソリューションのため)のIGMPv3のいずれかおよび/またはマルチキャストリスナー発見バージョン2(のMLDv2)(IPv6のソリューションのため)[RFC3810]のサポートが必要です。 PE-CEインターフェイスで双方向-PIMサポートが推奨されます。そして、導入を検討し、PIM-DMは、オプションと考えられています。

When a multicast VPN solution is built on a VPN solution supporting IPv6 unicast, it MUST also support v6 variants of the above protocols, including MLDv2, and PIM-SM IPv6-specific procedures. For a multicast VPN solution built on a unicast VPN solution supporting only IPv4, it is RECOMMENDED that the design favors the definition of procedures and encodings that will provide an easy adaptation to IPv6.

マルチキャストVPNソリューションがIPv6ユニキャストをサポートするVPNソリューションに基づいて構築されている場合、それはまたのMLDv2、およびPIM-SM IPv6固有の手順を含む上記プロトコルのV6変異体をサポートしなければなりません。 IPv4のみをサポートしているユニキャストVPNソリューション上に構築されたマルチキャストVPNソリューションのためには、設計がIPv6への容易な適応を提供し、手続きとエンコーディングの定義を支持することが推奨されます。

5.1.3. Quality of Service (QoS)
5.1.3. サービスの品質(QoS)

Firstly, general considerations regarding QoS in L3VPNs expressed in Section 5.5 of [RFC4031] are also relevant to this section.


QoS is measured in terms of delay, jitter, packet loss, and availability. These metrics are already defined for the current unicast PPVPN services and are included in Service Level Agreements (SLAs). In some cases, the agreed SLA may be different between unicast and multicast, and that will require differentiation mechanisms in order to monitor both SLAs.


The level of availability for the multicast service SHOULD be on par with what exists for unicast traffic. For instance, comparable traffic protection mechanisms SHOULD be available for customer multicast traffic when it is carried over the service provider's network.


A multicast VPN solution SHALL allow a service provider to define at least the same level of quality of service as exists for unicast, and as exists for multicast in a non-VPN context. From this perspective, the deployment of multicast-based services within an L3VPN environment SHALL benefit from Diffserv [RFC2475] mechanisms that include multicast traffic identification, classification, and marking capabilities, as well as multicast traffic policing, scheduling, and conditioning capabilities. Such capabilities MUST therefore be supported by any participating device in the establishment and the maintenance of the multicast distribution tunnel within the VPN.


As multicast is often used to deliver high-quality services such as TV broadcast, a multicast VPN solution MAY provide additional features to support high QoS such as bandwidth reservation and admission control.


Also, considering that multicast reception is receiver-triggered, group join delay (as defined in [RFC2432]) is also considered one important QoS parameter. It is thus RECOMMENDED that a multicast VPN solution be designed appropriately in this regard.


The group leave delay (as defined in [RFC2432]) may also be important on the CE-PE link for some usage scenarios: in cases where the typical bandwidth of multicast streams is close to the bandwidth of a PE-CE link, it will be important to have the ability to stop the emission of a stream on the PE-CE link as soon as it stops being requested by the CE, to allow for fast switching between two different high-throughput multicast streams. This implies that it SHOULD be possible to tune the multicast routing or group management protocols (e.g., IGMP/MLD or PIM) used on the PE-CE adjacency to reduce the group leave delay to the minimum.

ケースでマルチキャストストリームの典型的な帯域幅は、それが意志PE-CEリンクの帯域幅に近いです([RFC2432]で定義されるように)グループ離脱遅延はまた、いくつかの使用シナリオ用のCE-PEリンク上で重要であるかもしれませんそれは二つの異なる高スループットマルチキャストストリーム間の高速切り替えを可能にするために、CEによって要求されている停止するとすぐに、PE-CEリンク上のストリームの発光を停止させる能力を有することが重要です。これは、最小のグループ離脱遅延を低減するために、PE-CE隣接上で使用されるマルチキャストルーティングまたはグループ管理プロトコル(例えば、IGMP / MLDまたはPIM)調整することが可能でなければならないことを意味します。

Lastly, a multicast VPN solution SHOULD as much as possible ensure that client multicast traffic packets are neither lost nor duplicated, even when changes occur in the way a client multicast data stream is carried over the provider network. Packet loss issues also have to be considered when a new source starts to send traffic to a group: any receiver interested in receiving such traffic SHOULD be serviced accordingly.


5.1.4. Operations and Management
5.1.4. 運用と管理

The requirements and definitions for operations and management (OAM) of L3VPNs that are defined in [RFC4176] equally apply to multicast, and are not extensively repeated in this document. This sub-section mentions the most important guidelines and details points of particular relevance in the context of multicast in L3VPNs.


A multicast VPN solution SHOULD allow a multicast VPN customer to manage the capabilities and characteristics of their multicast VPN services.


A multicast VPN solution MUST support SLA monitoring capabilities, which SHOULD rely upon techniques similar to those used for the unicast service for the same monitoring purposes. Multicast SLA-related metrics SHOULD be available through means similar to the ones already used for unicast-related monitoring, such as Simple Network Management Protocol (SNMP) [RFC3411] or IPFIX [IPFIX-PROT].

マルチキャストVPNソリューションは、同一の監視目的のためにユニキャストサービスのために使用されるものと同様の技術に依存するべきであるSLA監視機能をサポートしなければなりません。マルチキャストSLA関連メトリックは、簡易ネットワーク管理プロトコル(SNMP)[RFC3411]またはIPFIX [IPFIX-PROT]として既にユニキャスト関連の監視のために使用されるものと同様の手段を介して利用可能であるべきです。

Multicast-specific characteristics that may be monitored include: multicast statistics per stream, end-to-end delay, and group join/ leave delay (time to start/stop receiving a multicast group's traffic across the VPN, as defined in [RFC2432], Section 3).


The monitoring of multicast-specific parameters and statistics MUST include multicast traffic statistics: total/incoming/outgoing/dropped traffic, by period of time. It MAY include IP Performance Metrics related information (IPPM, [RFC2330]) that is relevant to the multicast traffic usage: such information includes the one-way packet delay, the inter-packet delay variation, etc. See [MULTIMETRICS].


A generic discussion of SLAs is provided in [RFC3809].


Apart from statistics on multicast traffic, customers of a multicast VPN will need information concerning the status of their multicast resource usage (multicast routing states and bandwidth). Indeed, as mentioned in Section 5.2.5, for scalability purposes, a service provider may limit the number (and/or throughput) of multicast streams that are received/sent to/from a client site. In such a case, a multicast VPN solution SHOULD allow customers to find out their current resource usage (multicast routing states and throughput), and to receive some kind of feedback if their usage exceeds the agreed bounds. Whether this issue will be better handled at the protocol level at the PE-CE interface or at the Service Management Level interface [RFC4176] is left for further discussion.

別にマルチキャストトラフィックの統計から、マルチキャストVPNの顧客は、マルチキャストリソース使用量の状況(マルチキャストルーティングの状態と帯域幅)に関する情報が必要になります。スケーラビリティのために、セクション5.2.5で述べたように実際に、サービスプロバイダは、番号(及び/又はスループット)を制限することができるクライアントのサイトへ/から送信/受信されたマルチキャストストリームの。このような場合には、マルチキャストVPNソリューションは、顧客が現在のリソース使用量(マルチキャストルーティング状態及びスループット)を見つけるために可能にしなければならない、そしてそれらの使用は、合意された境界を超えた場合、フィードバックのいくつかの種類を受信します。この問題は、より良好な[RFC4176] PE-CEインターフェースにおけるプロトコルレベルまたはサービス管理レベルのインターフェイスで処理されるかどうかは、さらなる議論のために残されています。

It is RECOMMENDED that any OAM mechanism designed to trigger alarms in relation to performance or resource usage metrics integrate the ability to limit the rate at which such alarms are generated (e.g., some form of a hysteresis mechanism based on low/high thresholds defined for the metrics).


5.1.5. Security Requirements
5.1.5. セキュリティ要件

Security is a key point for a customer who uses a VPN service. For instance, the [RFC4364] model offers some guarantees concerning the security level of data transmission within the VPN.


A multicast VPN solution MUST provide an architecture with the same level of security for both unicast and multicast traffic.


Moreover, the activation of multicast features SHOULD be possible:


o per VRF / per VR


o per CE interface (when multiple CEs of a VPN are connected to a common VRF/VR)

CEインターフェイスあたりO(VPNの複数のCEが共通のVRFに接続されている/ VR)

o per multicast group and/or per channel


o with a distinction between multicast reception and emission


A multicast VPN solution may choose to make the optimality/ scalability trade-off stated in Section 3.3 by sometimes distributing multicast traffic of a client group to a larger set of PE routers that may include PEs that are not part of the VPN. From a security standpoint, this may be a problem for some VPN customers; thus, a multicast VPN solution using such a scheme MAY offer ways to avoid this for specific customers (and/or specific customer multicast streams).


5.1.6. Extranet
5.1.6. エクストラネット

In current PP L3VPN models, a customer site may be set up to be part of multiple VPNs, and this should still be possible when a VPN is multicast-enabled. In practice, it means that a VRF or VR can be part of more than one VPN.

現在のPP L3VPNモデルでは、顧客サイトは複数のVPNの一部であるように設定することができる、およびVPNがマルチキャストに対応しているとき、これはまだ可能でなければなりません。実際には、VRFまたはVRが複数のVPNの一部であることを意味します。

A multicast VPN solution MUST support such deployments.


For instance, it must be possible to configure a VRF so that an enterprise site participating in a BGP/MPLS multicast-enabled VPN and connected to that VRF can receive a multicast stream from (or originate a multicast stream towards) another VPN that would be associated to that VRF.

BGP / MPLSのマルチキャスト対応VPNに参加し、そのVRFに接続された企業のサイトからマルチキャストストリームを受信(又は向かってマルチキャストストリームを発信)であろう他のVPNができるように、例えば、VRFを設定することが可能でなければなりませんそのVRFに関連付けられています。

This means that a multicast VPN solution MUST offer means for a VRF to be configured so that multicast connectivity can be set up for a chosen set of extranet VPNs. More precisely, it MUST be possible to configure a VRF so that:


o receivers behind attached CEs can receive multicast traffic sourced in the configured set of extranet VPNs


o sources behind attached CEs can reach multicast traffic receivers located in the configured set of extranet VPNs


o multicast reception and emission can be independently enabled for each of the extranet VPNs


Moreover, a solution MUST allow service providers to control an extranet's multicast connectivity independently from the extranet's unicast connectivity. More specifically:


o enabling unicast connectivity to another VPN MUST be possible without activating multicast connectivity with that VPN


o enabling multicast connectivity with another VPN SHOULD NOT require more than the strict minimal unicast routing. Sending multicast to a VPN SHOULD NOT require having unicast routes to that VPN; receiving multicast from a VPN SHOULD be possible with nothing more than unicast routes to the relevant multicast sources of that VPN

別のVPNでマルチキャスト接続を可能oを厳密最小ユニキャストルーティングよりも多くを必要とすべきではありません。 VPNへのマルチキャストを送信すると、そのVPNへのユニキャストルートを持つ必要はありません。 VPNからのマルチキャストを受信すると、そのVPNの関連するマルチキャストソースへのユニキャストルートよりも何も可能であるべき

o when unicast routes from another VPN are imported into a VR/VRF, for multicast Reverse Path Forwarding (RPF) resolution, this SHOULD be possible without making those routes available for unicast routing

別のVPNからのユニキャストルートはVR / VRFにインポートされたときにO、マルチキャストリバースパス転送(RPF)解像度のため、これは、ユニキャストルーティングのためにそれらの経路を利用可能にすることなく可能であるべき

Proper support for this feature SHOULD NOT require replicating multicast traffic on a PE-CE link, whether it is a physical or logical link.


5.1.7. Internet Multicast
5.1.7. インターネットマルチキャスト

Connectivity with Internet Multicast is a particular case of the previous section, where sites attached to a VR/VRF would need to receive/send multicast traffic from/to the Internet.

インターネットマルチキャストとの接続には、VR / VRFに添付のサイトが/からのインターネットへのマルチキャストトラフィックを送信/受信する必要があるだろう、前のセクションの特定のケースです。

This should be considered OPTIONAL given the additional considerations, such as security, needed to fulfill the requirements for providing Internet Multicast.


5.1.8. Carrier's Carrier
5.1.8. キャリアのキャリア

Many L3 PPVPN solutions, such as [RFC4364] and [VRs], define the "Carrier's Carrier" model, where a "carrier's carrier" service provider supports one or more customer ISPs, or "sub-carriers". A multicast VPN solution SHOULD support the carrier's carrier model in a scalable and efficient manner.

このような[RFC4364]などの多くのL3 PPVPNソリューション、および[のVR]、「キャリアのキャリア」サービス・プロバイダは、1つのまたは複数の顧客のISP、または「サブキャリアを」サポート「キャリアのキャリア」モデルを定義します。マルチキャストVPNソリューションは、スケーラブルかつ効率的にキャリアのキャリアモデルをサポートする必要があります。

Ideally, the range of tunneling protocols available for the sub-carrier ISP should be the same as those available for the carrier's carrier ISP. This implies that the protocols that may be used at the PE-CE level SHOULD NOT be restricted to protocols required as per Section 5.1.2 and SHOULD include some of the protocols listed in Section 5.2.4, such as for instance P2MP MPLS signaling protocols.

理想的には、サブキャリアのISPのために利用可能なトンネリングプロトコルの範囲は、キャリアのキャリアISPのために利用可能なものと同じであるべきです。これは、PE-CEレベルで使用することができるプロトコルはセクション5.1.2に従って必要なプロトコルに限定されるものではないことを意味し、そのようなインスタンスP2MP MPLSシグナリングプロトコルのような、セクション5.2.4に記載されているプロトコルの一部を含むべきです。

In the context of MPLS-based L3VPN deployments, such as BGP/MPLS VPNs [RFC4364], this means that MPLS label distribution SHOULD happen at the PE-CE level, giving the ability to the sub-carrier to use multipoint LSPs as a tunneling mechanism.

そのようなBGP / MPLS VPNの[RFC4364]としてMPLSベースL3VPN配備のコンテキストでは、これは、MPLSラベル配布トンネリングとして多LSPを使用するサブキャリアする能力を与え、PE-CEレベルで起こるべきであることを意味します機構。

5.1.9. Multi-Homing, Load Balancing, and Resiliency
5.1.9. マルチホーミング、ロードバランシング、および復元力

A multicast VPN solution SHOULD be compatible with current solutions that aim at improving the service robustness for customers such as multi-homing, CE-PE link load balancing, and fail-over. A multicast VPN solution SHOULD also be able to offer those same features for multicast traffic.


Any solution SHOULD support redundant topology of CE-PE links. It SHOULD minimize multicast traffic disruption and fail-over.


5.1.10. RP Engineering
5.1.10. RPエンジニアリング

When PIM-SM (or bidir-PIM) is used in ASM mode on the VPN customer side, the RP function (or RP-address in the case of bidir-PIM) has to be associated to a node running PIM, and configured on this node.

PIM-SM(または双方向-PIM)がVPN顧客側のASMモードで使用される場合、RP機能(または双方向-PIMの場合にはRP-アドレス)PIMを実行するノードに関連付けられ、そして上に構成されなければなりませんこのノード。 RP Outsourcing。 RPのアウトソーシング

In the case of PIM-SM in ASM mode, engineering of the RP function requires the deployment of specific protocols and associated configurations. A service provider may offer to manage customers' multicast protocol operation on their behalf. This implies that it is necessary to consider cases where a customer's RPs are outsourced (e.g., on PEs). Consequently, a VPN solution MAY support the hosting of the RP function in a VR or VRF.

ASMモードでPIM-SMの場合は、RP機能のエンジニアリングは、特定のプロトコルと関連する構成を展開する必要があります。サービスプロバイダは、彼らに代わって顧客のマルチキャストプロトコルの動作を管理するために提供することがあります。顧客のRPが(例えば、PEの上)外部委託しているケースを考慮する必要があることを意味します。そのため、VPNソリューションは、VRまたはVRFにRP機能のホスティングをサポートするかもしれません。 RP Availability。 RPの可用性

Availability of the RP function (or address) is required for proper operation of PIM-SM (ASM mode) and bidir-PIM. Loss of connectivity to the RP from a receiver or source will impact the multicast service. For this reason, different mechanisms exist, such as BSR [PIM-BSR] or anycast-RP (Multicast Source Discovery Protocol (MSDP)- based [RFC3446] or PIM-based [RFC4610]).

RP機能(またはアドレス)の入手可能性は、PIM-SM(ASMモード)とのbidir-PIMの適切な動作のために必要とされます。受信機または送信元からRPへの接続の損失は、マルチキャストサービスに影響を与えます。この理由のために、異なるメカニズムが、このようなBSR [PIM-BSR]またはエニーキャスト-RPとして、存在する(マルチキャストソース発見プロトコル(MSDP) - ベースの[RFC3446]またはPIMベース[RFC4610])。

These protocols and procedures SHOULD work transparently through a multicast VPN, and MAY if relevant, be implemented in a VRF/VR.

これらのプロトコルおよび手順は、マルチキャストVPNを透過的に動作するはずですし、MAYは関連がある場合は、VRF / VRで実装します。

Moreover, a multicast VPN solution MAY improve the robustness of the ASM multicast service regarding loss of connectivity to the RP, by providing specific features that help: a) maintain ASM multicast service among all the sites within an MVPN that maintain connectivity among themselves, even when the site(s) hosting the RP lose their connectivity to the MVPN


b) maintain ASM multicast service within any site that loses connectivity to the service provider

b)は、サービスプロバイダへの接続を失った任意のサイト内のASMマルチキャストサービスを維持 RP Location。 RP場所

In the case of PIM-SM, when a source starts to emit traffic toward a group (in ASM mode), if sources and receivers are located in VPN sites that are different than that of the RP, then traffic may transiently flow twice through the SP network and the CE-PE link of the RP (from source to RP, and then from RP to receivers). This traffic peak, even short, may not be convenient depending on the traffic and link bandwidth.


Thus, a VPN solution MAY provide features that solve or help mitigate this potential issue.


5.1.11. Addressing
5.1.11. アドレッシング

A multicast provider-provisioned L3VPN SHOULD NOT impose restrictions on multicast group addresses used by VPN customers.


In particular, like unicast traffic, an overlap of multicast group address sets used by different VPN customers MUST be supported.


The use of globally unique means of multicast-based service identification at the scale of the domain where such services are provided SHOULD be recommended. For IPv4 multicast, this implies the use of the multicast administratively scoped range (239/8 as defined by [RFC2365]) for services that are to be used only inside the VPN, and of either SSM-range addresses (232/8 as defined by [RFC4607]) or globally assigned group addresses (e.g., GLOP [RFC3180], 233/8) for services for which traffic may be transmitted outside the VPN.

このようなサービスが提供されているドメインの規模でマルチキャストベースのサービス識別のグローバル一意手段の使用が推奨されるべきです。定義されるようなのIPv4マルチキャストのために、これは、VPN内で使用されるサービスのために、およびSSM範囲のアドレスのいずれかのマルチキャスト管理スコープ範囲(8分の239 [RFC2365]で定義されるように)(232/8の使用を意味します[RFC4607])によって、またはグローバルトラフィックがVPNの外部に送信することができるため、サービスのためのグループアドレス(例えば、GLOP [RFC3180]、8分の233)を割り当て。

5.1.12. Minimum MTU
5.1.12. 最小MTU

For customers, it is often a serious issue whether or not transmitted packets will be fragmented. In particular, some multicast applications might have different requirements than those that make use of unicast, and they may expect services that guarantee available packet length not to be fragmented.


Therefore, a multicast VPN solution SHOULD be designed with these considerations in mind. In practice: o the encapsulation overhead of a multicast VPN solution SHOULD be minimized, so that customer devices can be free of fragmentation and reassembly activity as much as possible


o a multicast VPN solution SHOULD enable the service provider to commit to a minimum path MTU usable by multicast VPN customers


o a multicast VPN solution SHOULD be compatible with path MTU discovery mechanisms (see [RFC1191] and [RFC4459]), and particular care SHOULD be given to means to help troubleshoot MTU issues


Moreover, since Ethernet LAN segments are often located at first and last hops, a multicast VPN solution SHOULD be designed to allow for a minimum 1500-byte IP MTU for VPN customers multicast packet, when the provider backbone design allows it.

イーサネットLANセグメントは、多くの場合、最初と最後のホップに位置しているので、マルチキャストVPNソリューションは、プロバイダのバックボーンデザインがそれを可能にする場合、VPNの顧客マルチキャストパケットの最小1500バイトのIP MTUを可能にするように設計する必要があります。

5.2. Service Provider Standpoint
5.2. サービスプロバイダの立場

Note: To avoid repetition and confusion with terms used in solution specifications, we introduced in Section 2.1 the term MDTunnel (for Multicast Distribution Tunnel), which designates the data plane means used by the service provider to forward customer multicast traffic over the core network.


5.2.1. General Requirement
5.2.1. 一般的な要件

The deployment of a multicast VPN solution SHOULD be possible with no (or very limited) impact on existing deployments of standardized multicast-related protocols on P and PE routers.


5.2.2. Scalability
5.2.2. スケーラビリティ

Some currently standardized and deployed L3VPN solutions have the major advantage of being scalable in the core regarding the number of customers and the number of customer routes. For instance, in the [RFC4364] and Virtual Router [VRs] models, a P router sees a number of MPLS tunnels that is only linked to the number of PEs and not to the number of VPNs, or customer sites.


As far as possible, this independence in the core, with respect to the number of customers and to customer activity, is recommended. Yet, it is recognized that in our context scalability and resource usage optimality are competing goals, so this requirement may be reduced to giving the possibility of bounding the quantity of states that the service provider needs to maintain in the core for MDTunnels, with a bound being independent of the multicast activity of VPN customers.


It is expected that multicast VPN solutions will use some kind of point-to-multipoint technology to efficiently carry multicast VPN traffic, and because such technologies require maintaining state information, this will use resources in the control plane of P and PE routers (memory and processing, and possibly address space).


Scalability is a key requirement for multicast VPN solutions. Solutions MUST be designed to scale well with an increase in any of the following:


o the number of PEs


o the number of customer VPNs (total and per PE)


o the number of PEs and sites in any VPN


o the number of client multicast channels (groups or source-groups)


Please consult Section 4.2 for typical orders of magnitude up to which a multicast VPN solution is expected to scale.


Scalability of both performance and operation MUST be considered.


Key considerations SHOULD include:


o the processing resources required by the control plane (neighborhood or session maintenance messages, keep-alives, timers, etc.)


o the memory resources needed for the control plane


o the amount of protocol information transmitted to manage a multicast VPN (e.g., signaling throughput)


o the amount of control plane processing required on PE and P routers to add or remove a customer site (or a customer from a multicast session)


o the number of multicast IP addresses used (if IP multicast in ASM mode is proposed as a multicast distribution tunnel)


o other particular elements inherent to each solution that impact scalability (e.g., if a solution uses some distribution tree inside the core, topology of the tree and number of leaf nodes may be some of them)


It is expected that the applicability of each solution will be evaluated with regards to the aforementioned scalability criteria.


These considerations naturally lead us to believe that proposed solutions SHOULD offer the possibility of sharing such resources between different multicast streams (between different VPNs, between different multicast streams of the same or of different VPNs). This means, for instance, if MDTunnels are trees, being able to share an MDTunnel between several customers.

これらの考慮事項は、自然に提案されたソリューションは、(異なるVPN間で、同じの異なるマルチキャストストリーム間や異なるVPNの)異なるマルチキャストストリームの間で、このようなリソースを共有する可能性を提供すべきであると信じて私たちを導きます。 MDTunnelsは、複数の顧客の間でMDTunnelを共有することができるという、木々ある場合、これは、例えば、意味しています。

Those scalability issues are expected to be more significant on P routers, but a multicast VPN solution SHOULD address both P and PE routers as far as scalability is concerned.


5.2.3. Resource Optimization
5.2.3. リソースの最適化 General Goals。一般的な目標

One of the aims of the use of multicast instead of unicast is resource optimization in the network.


The two obvious suboptimal behaviors that a multicast VPN solution would want to avoid are needless duplication (when the same data travels twice or more on a link, e.g., when doing ingress PE replication) and needless reception (e.g., a PE receiving traffic that it does not need because there are no downstream receivers).

マルチキャストVPNソリューションは避けたいと思う2つの明白な次善の行動が(入力PEのレプリケーションを行うときに同じデータが、例えば、リンクを2回以上移動する)不必要な重複や不必要な受信(例えば、PE受信トラフィックそれことです何の下流の受信機が存在しないため)必要はありません。 Trade-off and Tuning。トレードオフとチューニング

As previously stated in this document, designing a scalable solution that makes an optimal use of resources is considered difficult. Thus, what is expected from a multicast VPN solution is that it addresses the resource optimization issue while taking into account the fact that some trade-off has to be made.


Moreover, it seems that a "one size fits all" trade-off probably does not exist either. Thus, a multicast VPN solution SHOULD offer service providers appropriate configuration settings that let them tune the trade-off according to their particular constraints (network topology, platforms, customer applications, level of service offered etc.).


As an illustration, here are some example bounds of the trade-off space:


Bandwidth optimization: setting up optimized core MDTunnels whose topology (PIM or P2MP LSP trees, etc.) precisely follows a customer's multicast routing changes. This requires managing a large amount of state in the core, and also quick reactions of the core to customer multicast routing changes. This approach can be advantageous in terms of bandwidth, but it is poor in terms of state management.

帯域幅の最適化:トポロジ(PIMまたはP2MP LSP木、等)最適化されたコアMDTunnelsの設定を正確に顧客のマルチキャストルーティング変化に追従します。これは、顧客のマルチキャストルーティングの変更にコアの迅速な反応をコアに状態を大量に管理し、かつ必要があります。このアプローチは、帯域幅の面で有利であることができますが、それは国家管理の面で劣っています。

State optimization: setting up MDTunnels that aggregate multiple customer multicast streams (all or some of them, across different VPNs or not). This will have better scalability properties, but at the expense of bandwidth since some MDTunnel leaves will very likely receive traffic they don't need, and because increased constraints will make it harder to find optimal MDTunnels.

状態の最適化:複数の顧客のマルチキャスト・ストリーム(全てまたはそのうちのいくつか、異なるVPN間またはしない)を集計MDTunnelsを設定します。これは、より優れた拡張性の性質を持っていますが、一部のMDTunnelの葉は非常に可能性の高いトラフィックを受信しますので、帯域幅を犠牲にして彼らが必要としない、と増加した制約が行いますので、それは難しい最適MDTunnelsを見つけること。 Traffic Engineering。トラフィックエンジニアリング

If the VPN service provides traffic engineering (TE) features for the connection used between PEs for unicast traffic in the VPN service, the solution SHOULD provide equivalent features for multicast traffic.


A solution SHOULD offer means to support key TE objectives as defined in [RFC3272], for the multicast service.


A solution MAY also usefully support means to address multicast-specific traffic engineering issues: it is known that bandwidth resource optimization in the point-to-multipoint case is an NP-hard problem, and that techniques used for unicast TE may not be applicable to multicast traffic.


Also, it has been identified that managing the trade-off between resource usage and scalability may incur uselessly sending traffic to some PEs participating in a multicast VPN. For this reason, a multicast VPN solution MAY permit that the bandwidth/state tuning take into account the relative cost or availability of bandwidth toward each PE.


5.2.4. Tunneling Requirements
5.2.4. トンネルの要件 Tunneling Technologies。トンネリング技術

Following the principle of separation between the control plane and the forwarding plane, a multicast VPN solution SHOULD be designed so that control and forwarding planes are not interdependent: the control plane SHALL NOT depend on which forwarding plane is used (and vice versa), and the choice of forwarding plane SHOULD NOT be limited by the design of the solution. Also, the solution SHOULD NOT be tied to a specific tunneling technology.


In a multicast VPN solution extending a unicast L3 PPVPN solution, consistency in the tunneling technology has to be favored: such a solution SHOULD allow the use of the same tunneling technology for multicast as for unicast. Deployment consistency, ease of operation, and potential migrations are the main motivations behind this requirement.

ユニキャストL3 PPVPNソリューションを拡張マルチキャストVPNソリューションでは、トンネリング技術の一貫性が好まれなければならない。そのような溶液は、ユニキャストの場合とマルチキャストのための同一のトンネリング技術を使用することを可能にすべきです。展開の一貫性、操作の容易さ、および潜在的な移行は、この要件の背後にある主な動機です。

For MDTunnels, a solution SHOULD be able to use a range of tunneling technologies, including point-to-point and point-to-multipoint, such as:


o Generic Routing Encapsulation (GRE) [RFC2784] (including GRE in multicast IP trees),


o MPLS [RFC3031] (including P2P or MP2P tunnels, and multipoint tunnels signaled with MPLS P2MP extensions to the Resource Reservation Protocol (RSVP) [P2MP-RSVP-TE] or Label Distribution Protocol (LDP) [P2MP-LDP-REQS] [P2MP-LDP]),

MPLS O [RFC3031](P2PまたはMP2Pトンネル、およびリソース予約プロトコル(RSVP)[P2MP-RSVP-TE]またはラベル配布プロトコル(LDP)P2MP-LDP-REQS] [に対してMPLS P2MP拡張とシグナリングマルチポイントトンネルを含みますP2MP-LDP])、

o Layer-2 Tunneling Protocol (L2TP) (including L2TP for multicast [RFC4045]),


o IPsec [RFC4031]

OのIPsec [RFC4031]

o IP-in-IP [RFC2003], etc.

O IPインIP [RFC2003]など

Naturally, it is RECOMMENDED that a solution is built so that it can leverage the point-to-multipoint variants of these techniques. These variants allow for packet replications to happen along a tree in the provider core network, and they may help improve bandwidth efficiency in a multicast VPN context.

当然、これらの技術のポイント・ツー・マルチポイントのバリアントを活用できるように、ソリューションが構築されていることが推奨されます。これらの変異体は、パケットの複製は、プロバイダーのコアネットワークのツリーに沿って起こることを可能にし、彼らは、マルチキャストVPNコンテキストにおける帯域幅の効率を向上させることがあります。 MTU and Fragmentation。 MTUと断片化

A solution SHOULD support a method that provides the minimum MTU of the MDTunnel (e.g., to discover MTU, to communicate MTU via signaling, etc.) so that:


o fragmentation inside the MDTunnel does not happen, even when allowed by the underlying tunneling technology

O MDTunnel内部の断片化は、基本的なトンネリング技術によって許可された場合でも、発生しません

o proper troubleshooting can be performed if packets that are too big for the MDTunnel happen to be encapsulated in the MDTunnel


5.2.5. Control Mechanisms
5.2.5. 制御機構

The solution MUST provide some mechanisms to control the sources within a VPN. This control includes the number of sources that are entitled to send traffic on the VPN, and/or the total bit rate of all the sources.


At the reception level, the solution MUST also provide mechanisms to control the number of multicast groups or channels VPN users are entitled to subscribe to and/or the total bit rate represented by the corresponding multicast traffic.


All these mechanisms MUST be configurable by the service provider in order to control the amount of multicast traffic and state within a VPN.


Moreover, it MAY be desirable to be able to impose some bound on the quantity of state used by a VPN in the core network for its multicast traffic, whether on each P or PE router, or globally. The motivation is that it may be needed to avoid out-of-resources situations (e.g., out of memory to maintain PIM state if IP multicast is used in the core for multicast VPN traffic, or out of memory to maintain RSVP state if MPLS P2MP is used, etc.).

また、各P又はPEルータ上か、またはグローバルに、そのマルチキャストトラフィックのコアネットワークにVPNによって使用される状態量にいくらかのバウンドを課すことができることが望ましいかもしれません。動機は、IPマルチキャストがMPLS P2MP場合RSVP状態を維持するために、マルチキャストVPNトラフィックのため、またはメモリのうち、コアで使用されている場合PIM状態を維持するために、メモリのうち外のリソース状況(例えば、回避するために必要ことができることです)など、使用されています。

5.2.6. Support of Inter-AS, Inter-Provider Deployments
5.2.6. インターAS、インタープロバイダの展開のサポート

A solution MUST support inter-AS (Autonomous System) multicast VPNs, and SHOULD support inter-provider multicast VPNs. Considerations about coexistence with unicast inter-AS VPN Options A, B, and C (as described in Section 10 of [RFC4364]) are strongly encouraged.


A multicast VPN solution SHOULD provide inter-AS mechanisms requiring the least possible coordination between providers, and keep the need for detailed knowledge of providers' networks to a minimum -- all this being in comparison with corresponding unicast VPN options.

マルチキャストVPNソリューションは、プロバイダ間の最小限の調整を必要とAS間のメカニズムを提供し、最小限にプロバイダのネットワークの詳細な知識の必要性を保つべきである - これはすべてのユニキャストVPNオプションの対応と比較しています。

o Within each service provider, the service provider SHOULD be able on its own to pick the most appropriate tunneling mechanism to carry (multicast) traffic among PEs (just like what is done today for unicast)


o If a solution does require a single tunnel to span P routers in multiple ASs, the solution SHOULD provide mechanisms to ensure that the inter-provider coordination to set up such a tunnel is minimized


Moreover, such support SHOULD be possible without compromising other requirements expressed in this requirement document, and SHALL NOT incur penalties on scalability and bandwidth-related efficiency.


5.2.7. Quality-of-Service Differentiation
5.2.7. サービス品質差別化

A multicast VPN solution SHOULD give a VPN service provider the ability to offer, guarantee and enforce differentiated levels of QoS for its different customers.


5.2.8. Infrastructure security
5.2.8. インフラストラクチャセキュリティ

The solution SHOULD provide the same level of security for the service provider as what currently exists for unicast VPNs (for instance, as developed in the Security sections of [RFC4364] and [VRs]). For instance, traffic segregation and intrinsic protection against DoS (Denial of Service) and DDoS (Distributed Denial of Service) attacks of the BGP/MPLS VPN solution must be supported by the multicast solution.

([RFC4364]と[仮想ルーター]のセキュリティセクションに開発され、例えば)溶液は、現在、ユニキャストのVPNのために存在するもののようなサービス・プロバイダのセキュリティの同じレベルを提供すべきです。例えば、BGP / MPLS VPNソリューションのDoS攻撃(サービス妨害)攻撃やDDoS(サービス拒否の分散)攻撃に対するトラフィックの分離や固有の保護は、マルチキャストソリューションによってサポートされなければなりません。

Moreover, since multicast traffic and routing are intrinsically dynamic (receiver-initiated), some mechanism SHOULD be proposed so that the frequency of changes in the way client traffic is carried over the core can be bounded and not tightly coupled to dynamic changes of multicast traffic in the customer network. For example, multicast route dampening functions would be one possible mechanism.


Network devices that participate in the deployment and the maintenance of a given L3VPN MAY represent a superset of the participating devices that are also involved in the establishment and maintenance of the multicast distribution tunnels. As such, the activation of IP multicast capabilities within a VPN SHOULD be device-specific, not only to make sure that only the relevant devices will be multicast-enabled, but also to make sure that multicast (routing) information will be disseminated to the multicast-enabled devices only, hence limiting the risk of multicast-inferred DOS attacks.


Traffic of a multicast channel for which there are no members in a given multicast VPN MUST NOT be propagated within the multicast VPN, most particularly if the traffic comes from another VPN or from the Internet.


Security considerations are particularly important for inter-AS and inter-provider deployments. In such cases, it is RECOMMENDED that a multicast VPN solution support means to ensure the integrity and authenticity of multicast-related exchanges across inter-AS or inter-provider borders. It is RECOMMENDED that corresponding procedures require the least possible coordination between providers; more precisely, when specific configurations or cryptographic keys have to be deployed, this shall be limited to ASBRs (Autonomous System Border Routers) or a subset of them, and optionally BGP Route Reflectors (or a subset of them).


Lastly, control mechanisms described in Section 5.2.5 are also to be considered from this infrastructure security point of view.


5.2.9. Robustness
5.2.9. 丈夫

Resiliency is also crucial to infrastructure security; thus, a multicast VPN solution SHOULD either avoid single points of failures or propose some technical solution making it possible to implement a fail-over mechanism.


As an illustration, one can consider the case of a solution that would use PIM-SM as a means to set up MDTunnels. In such a case, the PIM RP might be a single point of failure. Such a solution SHOULD be compatible with a solution implementing RP resiliency, such as anycast-RP [RFC4610] or BSR [PIM-BSR].

例示として、一つはMDTunnelsを設定する手段として、PIM-SMを使用する溶液の場合を考慮することができます。そのような場合には、PIM RPは単一障害点であるかもしれません。そのような溶液は、エニーキャスト-RPの[用RFC4610]またはBSR [PIM-BSR]としてRPの弾力性を、実装溶液と相溶性であるべきです。

5.2.10. Operation, Administration, and Maintenance
5.2.10. 運用、管理、およびメンテナンス

The operation of a multicast VPN solution SHALL be as light as possible, and providing automatic configuration and discovery SHOULD be a priority when designing a multicast VPN solution. Particularly, the operational burden of setting up multicast on a PE or for a VR/ VRF SHOULD be as low as possible.

マルチキャストVPNソリューションの動作が可能なような光、およびマルチキャストVPNソリューションを設計する際の優先順位であるべきである自動構成および発見を提供するようにしなければなりません。特に、PE上またはVR / VRFのマルチキャストを設定するための作業負担は可能な限り低くすべきです。

Also, as far as possible, the design of a solution SHOULD carefully consider the number of protocols within the core network: if any additional protocols are introduced compared with the unicast VPN service, the balance between their advantage and operational burden SHOULD be examined thoroughly.


Moreover, monitoring of multicast-specific parameters and statistics SHOULD be offered to the service provider, following the requirements expressed in [RFC4176].


Most notably, the provider SHOULD have access to:


o Multicast traffic statistics (incoming/outgoing/dropped/total traffic conveyed, by period of time)


o Information about client multicast resource usage (multicast routing state and bandwidth usage)


o Alarms when limits are reached on such resources


o The IPPM (IP Performance Metrics [RFC2330])-related information that is relevant to the multicast traffic usage: such information includes the one-way packet delay, the inter-packet delay variation, etc.

O IPPM(IPパフォーマンス・メトリック[RFC2330]) - 関連情報マルチキャストトラフィックの使用に関連している:そのような情報は、一方向のパケット遅延、パケット間の遅延変動、等を含みます

o Statistics on decisions related to how client traffic is carried on distribution tunnels (e.g., "traffic switched onto a multicast tree dedicated to such groups or channels")


o Statistics on parameters that could help the provider to evaluate its optimality/state trade-off


This information SHOULD be made available through standardized SMIv2 [RFC2578] Management Information Base (MIB) modules to be used with SNMP [RFC3411], or through IPFIX [IPFIX-PROT]. For instance, in the context of BGP/MPLS VPNs [RFC4364], multicast extensions to MIBs defined in [RFC4382] SHOULD be proposed, with proper integration with [RFC3811], [RFC3812], [RFC3813], and [RFC3814] when applicable.

この情報は、SNMP [RFC3411]で使用される標準のSMIv2 [RFC2578]管理情報ベース(MIB)モジュールを介して、またはIPFIX [IPFIX-PROT]を介して利用できるようにすべきです。例えば、BGP / MPLS VPNの[RFC4364]、[RFC4382]で定義されたMIBにマルチキャスト拡張の​​文脈において、[RFC3811]、[RFC3812]、[RFC3813]及び[RFC3814]適用と適切に統合して、提案されてください。

Mechanisms similar to those described in Section 5.2.12 SHOULD also exist for proactive monitoring of the MDTunnels.


Proposed OAM mechanisms and procedures for multicast VPNs SHOULD be scalable with respect to the parameters mentioned in Section 5.2.2. In particular, it is RECOMMENDED that particular attention is given to the impact of monitoring mechanisms on performances and QoS.


Moreover, it is RECOMMENDED that any OAM mechanism designed to trigger alarms in relation to performance or resource usage metrics integrate the ability to limit the rate at which such alarms are generated (e.g., some form of a hysteresis mechanism based on low/ high thresholds defined for the metrics).


5.2.11. Compatibility and Migration Issues
5.2.11. 互換性と移行の問題

It is a requirement that unicast and multicast services MUST be able to coexist within the same VPN.


Likewise, a multicast VPN solution SHOULD be designed so that its activation in devices that participate in the deployment and maintenance of a multicast VPN SHOULD be as smooth as possible, i.e., without affecting the overall quality of the services that are already supported by the underlying infrastructure.


A multicast VPN solution SHOULD prevent compatibility and migration issues, for instance, by focusing on providing mechanisms facilitating forward compatibility. Most notably, a solution supporting only a subset of the requirements expressed in this document SHOULD be designed to allow compatibility to be introduced in further revisions.


It SHOULD be an aim of any multicast VPN solution to offer as much backward compatibility as possible. Ideally, a solution would have the ability to offer multicast VPN services across a network containing some legacy routers that do not support any multicast VPN-specific features.


In any case, a solution SHOULD state a migration policy from possibly existing deployments.


5.2.12. Troubleshooting
5.2.12. トラブルシューティング

A multicast VPN solution that dynamically adapts the way some client multicast traffic is carried over the provider's network may incur the disadvantage of being hard to troubleshoot. In such a case, to help diagnose multicast network issues, a multicast VPN solution SHOULD provide monitoring information describing how client traffic is carried over the network (e.g., if a solution uses multicast-based MDTunnels, which provider multicast group is used for a given client multicast stream). A solution MAY also provide configuration options to avoid any dynamic changes, for multicast traffic of a particular VPN or a particular multicast stream.


Moreover, a solution MAY provide mechanisms that allow network operators to check that all VPN sites that advertised interest in a particular customer multicast stream are properly associated with the corresponding MDTunnel. Providing operators with means to check the proper setup and operation of MDTunnels MAY also be provided (e.g., when P2MP MPLS is used for MDTunnels, troubleshooting functionalities SHOULD integrate mechanisms compliant with [RFC4687], such as LSP Ping [RFC4379][LSP-PING]). Depending on the implementation, such verification could be initiated by a source-PE or a receiver-PE.

また、解決策は、ネットワークオペレータは、特定の顧客マルチキャストストリームに関心をアドバタイズされたすべてのVPNサイトが適切に対応MDTunnelに関連付けられていることを確認することを可能にするメカニズムを提供することができます。 MDTunnelsの適切なセットアップや操作を確認する手段をオペレータに提供することもP2MP MPLSをMDTunnelsのために使用される場合(例えば、トラブルシューティング機能は、LSP Pingのように、[RFC4379]を[RFC4687]に準拠したメカニズムを統合する必要が提供されてもよい[LSP-PING ])。実装に応じて、そのような検証は、ソース-PEまたは受信-PEによって開始することができます。

6. Security Considerations

This document does not by itself raise any particular security issue.


A set of security issues has been identified that MUST be addressed when considering the design and deployment of multicast-enabled L3 PPVPNs. Such issues have been described in Section 5.1.5 and Section 5.2.8.

セキュリティ問題のセットは、マルチキャスト対応のL3 PPVPNsの設計と導入を検討する際に対処する必要があることを確認されています。このような問題は、5.1.5項および5.2.8項に記載されています。

7. Contributors

The main contributors to this document are listed below, in alphabetical order:


o Christian Jacquenet France Telecom 3, avenue Francois Chateau CS 36901 35069 RENNES Cedex, France Email:

OクリスチャンJacquenetフランステレコム3、大通りフランソワ・シャトーCS 36901 35069のレンヌセデックス、フランスEメール

o Yuji Kamite NTT Communications Corporation Tokyo Opera City Tower 3-20-2 Nishi Shinjuku, Shinjuku-ku Tokyo 163-1421, Japan Email:

お ゆじ かみて んっt こっむにかちおんs こrぽらちおん ときょ おぺら しty とうぇr 3ー20ー2 にし しんじゅく、 しんじゅくーく ときょ 163ー1421、 じゃぱん えまいl: y。かみて@んっt。こm

o Jean-Louis Le Roux France Telecom R&D 2, avenue Pierre-Marzin 22307 Lannion Cedex, France Email:

Oジャン=ルイ・ルーフランステレコムR&D 2、大通りピエールMarzin 22307ラニオンセデックス、フランスEメール

o Nicolai Leymann Deutsch Telecom Engineering Networks, Products & Services Goslarer Ufer 3510589 Berlin, Germany Email:


o Renaud Moignard France Telecom R&D 2, avenue Pierre-Marzin 22307 Lannion Cedex, France Email:

OルノーMoignardフランステレコムR&D 2、大通りピエールMarzin 22307ラニオンセデックス、フランスEメール

o Thomas Morin France Telecom R&D 2, avenue Pierre-Marzin 22307 Lannion Cedex, France Email:

Oトーマス・モリンフランステレコムR&D 2、大通りピエールMarzin 22307ラニオンセデックス、フランスEメール

8. Acknowledgments

The authors would like to thank, in rough chronological order, Vincent Parfait, Zubair Ahmad, Elodie Hemon-Larreur, Sebastien Loye, Rahul Aggarwal, Hitoshi Fukuda, Luyuan Fang, Adrian Farrel, Daniel King, Yiqun Cai, Ronald Bonica, Len Nieman, Satoru Matsushima, Netzahualcoyotl Ornelas, Yakov Rekhter, Marshall Eubanks, Pekka


Savola, Benjamin Niven-Jenkins, and Thomas Nadeau, for their review, valuable input, and feedback.


We also thank the people who kindly answered the survey, and Daniel King, who took care of gathering and anonymizing its results.


9. References
9.1. Normative References
9.1. 引用規格

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.

[RFC2119]ブラドナーの、S.、 "要件レベルを示すためにRFCsにおける使用のためのキーワード"、BCP 14、RFC 2119、1997年3月。

[RFC4031] Carugi, M. and D. McDysan, "Service Requirements for Layer 3 Provider-Provisioned Virtual Private Networks (PPVPNs)", RFC 4031, April 2005.

[RFC4031] Carugi、M.とD. McDysan、 "レイヤ3プロバイダ・プロビジョニングされた仮想プライベートネットワーク(PPVPNs)のためのサービスの要件"、RFC 4031、2005年4月。

[RFC4026] Andersson, L. and T. Madsen, "Provider-Provisioned Virtual Private Network (VPN) Terminology", RFC 4026, March 2005.

[RFC4026]アンデションとL.とT.マドセン、 "プロバイダ・プロビジョニングされた仮想プライベートネットワーク(VPN)用語"、RFC 4026、2005年3月。

[RFC4601] Fenner, B., Handley, M., Holbrook, H., and I. Kouvelas, "Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised)", RFC 4601, August 2006.

[RFC4601]フェナー、B.、ハンドリー、M.、ホルブルック、H.、およびI. Kouvelas、 "プロトコル独立マルチキャスト - スパースモード(PIM-SM):プロトコル仕様(改訂)"、RFC 4601、2006年8月。

[RFC4607] Holbrook, H. and B. Cain, "Source-Specific Multicast for IP", RFC 4607, August 2006.

[RFC4607]ホルブルック、H.、およびB.カイン、 "IPのためのソース固有のマルチキャスト"、RFC 4607、2006年8月。

[RFC3376] Cain, B., Deering, S., Kouvelas, I., Fenner, B., and A. Thyagarajan, "Internet Group Management Protocol, Version 3", RFC 3376, October 2002.

[RFC3376]カイン、B.、デアリング、S.、Kouvelas、I.、フェナー、B.、およびA. Thyagarajan、 "インターネットグループ管理プロトコル、バージョン3"、RFC 3376、2002年10月。

[RFC3810] Vida, R. and L. Costa, "Multicast Listener Discovery Version 2 (MLDv2) for IPv6", RFC 3810, June 2004.

"IPv6のマルチキャストリスナ発見バージョン2(MLDv2の)" [RFC3810]ヴィーダ、R.とL.コスタ、RFC 3810、2004年6月。

[RFC4176] El Mghazli, Y., Nadeau, T., Boucadair, M., Chan, K., and A. Gonguet, "Framework for Layer 3 Virtual Private Networks (L3VPN) Operations and Management", RFC 4176, October 2005.

[RFC4176]エルMghazli、Y.、ナドー、T.、Boucadair、M.、チャン、K.、およびA. Gonguet、RFC 4176、 "レイヤ3仮想プライベートネットワーク(L3VPN)運用と管理のための枠組み" 2005年10月。

[RFC3973] Adams, A., Nicholas, J., and W. Siadak, "Protocol Independent Multicast - Dense Mode (PIM-DM): Protocol Specification (Revised)", RFC 3973, January 2005.

[RFC3973]アダムス、A.、ニコラス、J.、およびW. Siadak、 "プロトコル独立マルチキャスト - 稠密モード(PIM-DM):プロトコル仕様(改訂)"、RFC 3973、2005年1月。

9.2. Informative References
9.2. 参考文献

[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private Networks (VPNs)", RFC 4364, February 2006.

[RFC4364]ローゼン、E.およびY. Rekhter、 "BGP / MPLS IP仮想プライベートネットワーク(VPN)"、RFC 4364、2006年2月。

[VRs] Ould-Brahim, H., "Network based IP VPN Architecture Using Virtual Routers", Work in Progress, March 2006.

、進歩、2006年3月に仕事[のVR]ウルド - Brahimの、H.、「仮想ルーターを使用してIP VPNアーキテクチャをベースとネットワーク」。

[RFC2432] Dubray, K., "Terminology for IP Multicast Benchmarking", RFC 2432, October 1998.

[RFC2432] Dubray、K.、RFC 2432、1998年10月 "IPマルチキャストベンチマーキングのための用語"。

[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol Label Switching Architecture", RFC 3031, January 2001.

[RFC3031]ローゼン、E.、Viswanathanの、A.、およびR. Callon、 "マルチプロトコルラベルスイッチングアーキテクチャ"、RFC 3031、2001年1月。

[RFC1112] Deering, S., "Host extensions for IP multicasting", STD 5, RFC 1112, August 1989.

[RFC1112]デアリング、S.、STD 5、RFC 1112 "IPマルチキャスティングのためのホスト拡大"、1989年8月。

[RFC2236] Fenner, W., "Internet Group Management Protocol, Version 2", RFC 2236, November 1997.

[RFC2236]フェナー、W.、 "インターネットグループ管理プロトコル、バージョン2"、RFC 2236、1997年11月。

[P2MP-RSVP-TE] Aggarwal, R., "Extensions to RSVP-TE for Point-to-Multipoint TE LSPs", Work in Progress, August 2006.

[P2MP-RSVP-TE]アガルワル、R.は、進捗状況、2006年8月に、仕事を "拡張機能は、ポイント・ツー・マルチポイントTE LSPのための-TEをRSVPに"。

[PIM-BSR] Bhaskar, N., "Bootstrap Router (BSR) Mechanism for PIM", Work in Progress, June 2006.

[PIM-BSR] Bhaskar、N.、 "PIMのためのブートストラップルータ(BSR)メカニズム"、進歩、2006年6月に作業。

[RFC4610] Farinacci, D. and Y. Cai, "Anycast-RP Using Protocol Independent Multicast (PIM)", RFC 4610, August 2006.

[RFC4610]ファリナッチ、D.およびY.カイ、RFC 4610、2006年8月 "Protocol Independent Multicast(PIM)を使用してエニーキャストRP-"。

[RFC3446] Kim, D., Meyer, D., Kilmer, H., and D. Farinacci, "Anycast Rendevous Point (RP) mechanism using Protocol Independent Multicast (PIM) and Multicast Source Discovery Protocol (MSDP)", RFC 3446, January 2003.

[RFC3446]キム、D.、マイヤー、D.、キルマー、H.、およびD.ファリナッチ、 "エニーキャストRendevousポイント(RP)プロトコル独立マルチキャスト(PIM)とMulticast Source Discovery Protocol(MSDP)を用いた機構" を、RFC 3446 、2003年1月。

[P2MP-LDP] Minei, I., "Label Distribution Protocol Extensions for Point-to-Multipoint and Multipoint-to-Multipoint Label Switched Paths", Work in Progress, October 2006.

[P2MP-LDP] Mineiは、I.は、進歩、2006年10月に、仕事を「のラベル配布プロトコルの拡張機能は、ポイント・ツー・マルチポイントおよびマルチポイント・ツー・マルチラベルパスの交換しました」。

[P2MP-LDP-REQS] Roux, J., "Requirements for point-to-multipoint extensions to the Label Distribution Protocol", Work in Progress, June 2006.


[RFC4687] Yasukawa, S., Farrel, A., King, D., and T. Nadeau, "Operations and Management (OAM) Requirements for Point-to-Multipoint MPLS Networks", RFC 4687, September 2006.

[RFC4687]安川、S.、ファレル、A.、キング、D.、およびT.ナドー、 "操作とポイントツーマルチポイントMPLSネットワークの管理(OAM)要件"、RFC 4687、2006年9月。

[BIDIR-PIM] Handley, M., "Bi-directional Protocol Independent Multicast (BIDIR-PIM)", Work in Progress, October 2005.

[BIDIR-PIM]ハンドリー、M.、 "双方向プロトコル独立マルチキャスト(BIDIR-PIM)"、進歩、2005年10月に作業。

[RFC2003] Perkins, C., "IP Encapsulation within IP", RFC 2003, October 1996.

[RFC2003]パーキンス、C.、 "IP内IPカプセル化"、RFC 2003、1996年10月。

[RFC3353] Ooms, D., Sales, B., Livens, W., Acharya, A., Griffoul, F., and F. Ansari, "Overview of IP Multicast in a Multi-Protocol Label Switching (MPLS) Environment", RFC 3353, August 2002.

[RFC3353] Ooms、D.、販売、B.、Livens、W.、アチャリヤ、A.、Griffoul、F.、およびF.アンサリ、 "マルチプロトコルラベルでのIPマルチキャストの概要(MPLS)環境の切り替え" 、RFC 3353、2002年8月。

[RFC3272] Awduche, D., Chiu, A., Elwalid, A., Widjaja, I., and X. Xiao, "Overview and Principles of Internet Traffic Engineering", RFC 3272, May 2002.

[RFC3272] Awduche、D.、チウ、A.、Elwalid、A.、Widjaja、I.、およびX.シャオ、 "インターネットトラフィックエンジニアリングの概要と原則"、RFC 3272、2002年5月。

[RFC2784] Farinacci, D., Li, T., Hanks, S., Meyer, D., and P. Traina, "Generic Routing Encapsulation (GRE)", RFC 2784, March 2000.

[RFC2784]ファリナッチ、D.、李、T.、ハンクス、S.、マイヤー、D.、およびP. Trainaの、 "総称ルーティングカプセル化(GRE)"、RFC 2784、2000年3月。

[IPFIX-PROT] Claise, B., "Specification of the IPFIX Protocol for the Exchange", Work in Progress, November 2006.

[IPFIX-PROT] Claise、B.、 "ExchangeのIPFIXプロトコルの仕様"、進歩、2006年11月に作業。

[RFC4045] Bourdon, G., "Extensions to Support Efficient Carrying of Multicast Traffic in Layer-2 Tunneling Protocol (L2TP)", RFC 4045, April 2005.

[RFC4045]ブルドン、G.、 "レイヤ2トンネリングプロトコル(L2TP)にマルチキャストトラフィックの効率的なキャリングをサポートする拡張機能"、RFC 4045、2005年4月。

[RFC3809] Nagarajan, A., "Generic Requirements for Provider-Provisioned Virtual Private Networks (PPVPN)", RFC 3809, June 2004.

[RFC3809] Nagarajan、A.、 "プロバイダ・プロビジョニングされた仮想プライベートネットワークのための一般的要件(PPVPN)"、RFC 3809、2004年6月。

[RFC3811] Nadeau, T. and J. Cucchiara, "Definitions of Textual Conventions (TCs) for Multiprotocol Label Switching (MPLS) Management", RFC 3811, June 2004.

[RFC3811]ナドー、T.、およびJ. Cucchiara、RFC 3811、2004年6月 "マルチプロトコルラベルスイッチング(MPLS)管理のためのテキストの表記法(TCS)の定義"。

[RFC3812] Srinivasan, C., Viswanathan, A., and T. Nadeau, "Multiprotocol Label Switching (MPLS) Traffic Engineering (TE) Management Information Base (MIB)", RFC 3812, June 2004.

[RFC3812]スリニバサン、C.、Viswanathanの、A.、およびT.ナドー、 "マルチプロトコルラベルスイッチング(MPLS)トラフィックエンジニアリング(TE)管理情報ベース(MIB)"、RFC 3812、2004年6月。

[RFC3813] Srinivasan, C., Viswanathan, A., and T. Nadeau, "Multiprotocol Label Switching (MPLS) Label Switching Router (LSR) Management Information Base (MIB)", RFC 3813, June 2004.

[RFC3813]スリニバサン、C.、Viswanathanの、A.、およびT.ナドーは、 "マルチプロトコルラベルスイッチング(MPLS)ラベルスイッチングルータ(LSR)管理情報ベース(MIB)"、RFC 3813、2004年6月。

[RFC3814] Nadeau, T., Srinivasan, C., and A. Viswanathan, "Multiprotocol Label Switching (MPLS) Forwarding Equivalence Class To Next Hop Label Forwarding Entry (FEC-To-NHLFE) Management Information Base (MIB)", RFC 3814, June 2004.

[RFC3814]ナドー、T.、スリニヴァサン、C.、およびA. Viswanathanの、 "マルチプロトコルラベルスイッチング(MPLS)、転送等価クラスへのネクストホップラベル転送エントリ(FEC-TO-NHLFE)管理情報ベース(MIB)"、RFC 3814、2004年6月。

[RFC2365] Meyer, D., "Administratively Scoped IP Multicast", BCP 23, RFC 2365, July 1998.

[RFC2365]マイヤー、D.、 "管理スコープのIPマルチキャスト"、BCP 23、RFC 2365、1998年7月。

[RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis, "Framework for IP Performance Metrics", RFC 2330, May 1998.

[RFC2330]パクソン、V.、Almes、G.、Mahdavi、J.、およびM.マティス、 "IPパフォーマンス・メトリックのためのフレームワーク"、RFC 2330、1998年5月。

[MULTIMETRICS] Stephan, E., "IP Performance Metrics (IPPM) for spatial and multicast", Work in Progress, October 2006.

[MULTIMETRICS] "空間とマルチキャストのためのIPパフォーマンス・メトリック(IPPM)" ステファン、E.、進歩、2006年10月に作業。

[RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z., and W. Weiss, "An Architecture for Differentiated Services", RFC 2475, December 1998.

[RFC2475]ブレイク、S.、ブラ​​ック、D.、カールソン、M.、デイヴィス、E.、王、Z.、およびW.ワイス、 "差別化サービスのためのアーキテクチャ"、RFC 2475、1998年12月。

[RFC3180] Meyer, D. and P. Lothberg, "GLOP Addressing in 233/8", BCP 53, RFC 3180, September 2001.

[RFC3180]マイヤー、D.およびP. Lothberg、 "8分の233にアドレッシングGLOP"、BCP 53、RFC 3180、2001年9月。

[RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks", STD 62, RFC 3411, December 2002.

[RFC3411]ハリントン、D.、Presuhn、R.、およびB. Wijnenの、 "簡易ネットワーク管理プロトコル(SNMP)管理フレームワークを記述するためのアーキテクチャ"、STD 62、RFC 3411、2002年12月。

[RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.

[RFC2578] McCloghrie、K.、エド。、パーキンス、D.、編、及びJ. Schoenwaelder、編、STD 58、RFC 2578、1999年4月、 "管理情報バージョン2(SMIv2)の構造"。

[RFC1191] Mogul, J. and S. Deering, "Path MTU discovery", RFC 1191, November 1990.

[RFC1191]ムガール人、J.とS.デアリング、 "パスMTUディスカバリ"、RFC 1191、1990年11月。

[RFC4382] Nadeau, T. and H. van der Linde, "MPLS/BGP Layer 3 Virtual Private Network (VPN) Management Information Base", RFC 4382, February 2006.

[RFC4382]ナドー、T.とH.ファンデリンデ、 "MPLS / BGPレイヤ3仮想プライベートネットワーク(VPN)管理情報ベース"、RFC 4382、2006年2月。

[RFC4379] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label Switched (MPLS) Data Plane Failures", RFC 4379, February 2006.

[RFC4379] Kompella、K.とG.ツバメ、2006年2月、RFC 4379 "を検出マルチプロトコルラベルは(MPLS)データプレーン障害をスイッチ"。

[LSP-PING] Farrel, A. and S. Yasukawa, "Detecting Data Plane Failures in Point-to-Multipoint Multiprotocol", Work in Progress, September 2006.


[RFC4459] Savola, P., "MTU and Fragmentation Issues with In-the-Network Tunneling", RFC 4459, April 2006.

[RFC4459]、RFC 4459 Savola、P.、 "イン・ネットワークのトンネリングを使用したMTUと断片化の問題"、2006年4月。

Author's Address


Thomas Morin (editor) France Telecom R&D 2, avenue Pierre Marzin Lannion 22307 France

トーマス・モリン(編集者)フランステレコムR&D 2、大通りピエールMarzin 22307ラニオンフランス



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