Network Working Group N. Shen, Ed.
Request for Comments: 5309 Cisco Systems
Category: Informational A. Zinin, Ed.
Alcatel-Lucent
October 2008
Network Working Group N. Shen, Ed.
Request for Comments: 5309 Cisco Systems
Category: Informational A. Zinin, Ed.
Alcatel-Lucent
October 2008
Point-to-Point Operation over LAN in Link State Routing Protocols
链路状态路由协议中局域网上的点对点操作
Status of This Memo
关于下段备忘
This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
本备忘录为互联网社区提供信息。它没有规定任何类型的互联网标准。本备忘录的分发不受限制。
Abstract
摘要
The two predominant circuit types used by link state routing protocols are point-to-point and broadcast. It is important to identify the correct circuit type when forming adjacencies, flooding link state database packets, and representing the circuit topologically. This document describes a simple mechanism to treat the broadcast network as a point-to-point connection from the standpoint of IP routing.
链路状态路由协议使用的两种主要电路类型是点对点和广播。在形成邻接、泛洪链路状态数据库数据包以及在拓扑上表示电路时，识别正确的电路类型非常重要。本文档描述了一种从IP路由的角度将广播网络视为点对点连接的简单机制。
Point-to-point and broadcast are the two predominant circuit types used by link state routing protocols such as IS-IS [ISO10589] [RFC1195] and OSPF [RFC2328] [RFC5340]. They are treated differently with respect to establishing neighbor adjacencies, flooding link state information, representing the topology, and calculating the Shortest Path First (SPF) and protocol packets. The most important differences are that broadcast circuits utilize the concept of a designated router and are represented topologically as virtual nodes in the network topology graph.
点对点和广播是链路状态路由协议（如IS-IS[ISO10589][RFC1195]和OSPF[RFC2328][RFC5340]）使用的两种主要电路类型。在建立邻居邻接、泛洪链路状态信息、表示拓扑以及计算最短路径优先（SPF）和协议数据包方面，它们的处理方式不同。最重要的区别在于广播电路利用指定路由器的概念，并在网络拓扑图中以虚拟节点的形式进行拓扑表示。
Compared with broadcast circuits, point-to-point circuits afford more straightforward IGP operation. There is no designated router involved, and there is no representation of the pseudonode or network Link State Advertisement (LSA) in the link state database. For IS-IS, there also is no periodic database synchronization. Conversely, if there are more than two routers on the LAN media, the traditional view of the broadcast circuit will reduce the routing information in the network.
与广播电路相比，点对点电路提供更直接的IGP操作。没有指定的路由器，链路状态数据库中也没有伪节点或网络链路状态公告（LSA）的表示。对于IS-IS，也没有定期的数据库同步。相反，如果LAN媒体上有两个以上的路由器，则广播电路的传统视图将减少网络中的路由信息。
When there are only two routers on the LAN, it makes more sense to treat the connection between the two routers as a point-to-point circuit. This document describes the mechanism to allow link state routing protocols to operate using point-to-point connections over a LAN under this condition. Some implications related to forwarding IP packets on this type of circuit are also discussed. We will refer to this as a p2p-over-lan circuit in this document.
当LAN上只有两个路由器时，将两个路由器之间的连接视为点对点电路更有意义。本文档描述了允许链路状态路由协议在这种情况下通过LAN上的点对点连接运行的机制。还讨论了在这种电路上转发IP数据包的一些含义。在本文档中，我们将其称为p2p over lan电路。
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 RFC 2119 [RFC2119].
本文件中的关键词“必须”、“不得”、“要求”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照RFC 2119[RFC2119]中所述进行解释。
Even though a broadcast circuit is meant to handle more than two devices, there are cases where only two routers are connected over either the physical or logical LAN segment:
即使广播电路用于处理两个以上的设备，也存在只有两个路由器通过物理或逻辑LAN段连接的情况：
1. The media itself is being used for point-to-point operation between two routers. This is mainly for long-haul operation. 2. There are only two routers on the physical LAN. 3. There are only two routers on a virtual LAN (vLAN).
1. 介质本身用于两个路由器之间的点对点操作。这主要用于长途作业。2.物理LAN上只有两个路由器。3.虚拟LAN（vLAN）上只有两个路由器。
In any of the above cases, the link state routing protocols will normally still treat the media as a broadcast circuit. Hence, they will have the overhead involved with protocol LAN operation without the benefits of reducing routing information and optimized flooding.
在上述任何情况下，链路状态路由协议通常仍将媒体视为广播电路。因此，它们将具有协议LAN操作所涉及的开销，而不会带来减少路由信息和优化泛洪的好处。
Being able to treat a LAN as a point-to-point circuit provides the benefit of reduction in the amount of information routing protocols must carry and manage. DR/DIS (Designated Router / Designated Intermediate System) election can be omitted. Flooding can be done as in p2p links without the need for using "LSA reflection" by the DR in OSPF or periodic Complete Sequence Number Packets (CSNPs) in IS-IS.
将局域网视为点对点电路可以减少路由协议必须携带和管理的信息量。可以省略DR/DIS（指定路由器/指定中间系统）选择。可以像在p2p链路中一样进行泛洪，而无需在OSPF中使用DR的“LSA反射”，也无需在IS-IS中使用周期性完整序列号数据包（CSNP）。
Also, if a broadcast segment wired as a point-to-point link can be treated as a point-to-point link, only the connection between the two routers would need to be advertised as a topological entity.
此外，如果作为点到点链路连接的广播段可以被视为点到点链路，则只有两个路由器之间的连接需要作为拓扑实体进行广告。
Even when there are multiple routers on the LAN, an ISP may want to sub-group the routers into multiple vLANs, since this allows them to assign different costs to IGP neighbors. When there are only two routers in some of the vLANs, this LAN can be viewed by the IGP as a mesh of point-to-point connections.
即使LAN上有多个路由器，ISP也可能希望将路由器分组到多个VLAN中，因为这允许它们为IGP邻居分配不同的成本。当某些VLAN中只有两个路由器时，IGP可以将该LAN视为点对点连接的网状结构。
The IP unnumbered configuration is widely used in networks. It enables IP processing on a point-to-point interface without an explicit IP address. The IP unnumbered interface can "borrow" the IP address of another interface on the node. The advantages of unnumbered point-to-point links are obvious in the current IP addressing environment where addresses are a scarce resource. The unnumbered interface can also be applied over p2p-over-lan circuits. Separating the concept of network type from media type will allow LANs, e.g., ethernet, to be unnumbered and realize the IP address space savings. Another advantage is in simpler network management and configuration. In the case of an IPv6 network, a link local address used in IS-IS [RFC5308] and OSPFv3 [RFC5340] serves the same purpose.
IP无编号配置广泛应用于网络中。它在没有显式IP地址的点到点接口上启用IP处理。IP未编号接口可以“借用”节点上另一个接口的IP地址。在当前的IP寻址环境中，地址是一种稀缺资源，无编号的点到点链路的优势是显而易见的。未编号的接口也可以应用于局域网上的p2p电路。将网络类型的概念与媒体类型分离将允许局域网（如以太网）不编号，并实现IP地址空间节约。另一个优点是更简单的网络管理和配置。在IPv6网络的情况下，IS-IS[RFC5308]和OSPFv3[RFC5340]中使用的链路本地地址具有相同的用途。
When an IP network includes multi-access segments, each segment is usually assigned a separate subnet, and each router connected to it is assigned a distinct IP address within that subnet. The role of the IP address assigned to a multi-access interface can be outlined as follows:
当一个IP网络包括多个访问段时，每个段通常被分配一个单独的子网，每个连接到它的路由器在该子网内被分配一个不同的IP地址。分配给多址接口的IP地址的作用可概述如下：
1. Source IP address - The interface address can be used by the router as the source IP address in locally originated IP packets that are destined for that subnet or have a best path next hop on that subnet.
1. 源IP地址-路由器可以将该接口地址用作本地IP数据包中的源IP地址，这些数据包的目的地为该子网，或者在该子网的下一跳具有最佳路径。
2. Destination IP address - The interface address can be used by other devices in the network as a destination address for packets to router applications (examples include telnet, SMTP, TFTP, OSPF, BGP, etc).
2. 目标IP地址-网络中的其他设备可以将接口地址用作路由器应用程序数据包的目标地址（示例包括telnet、SMTP、TFTP、OSPF、BGP等）。
3. Next-hop identifier - If other routers connected to the same segment need to forward traffic through the router, the corresponding routes in their routing tables will include the router's interface IP address. This address will be used to find the router's MAC (Media Access Control) address using the ARP/ND (Address Resolution Protocol / Neighbor Discovery) protocol. Effectively, the interface IP addresses help other routers find the data-link layer details that are required to specify the destination of the encapsulating data-link frame when it is sent on the segment.
3. 下一跳标识符-如果连接到同一段的其他路由器需要通过路由器转发流量，则其路由表中的相应路由将包括路由器的接口IP地址。此地址将用于使用ARP/ND（地址解析协议/邻居发现）协议查找路由器的MAC（媒体访问控制）地址。实际上，接口IP地址可以帮助其他路由器找到数据链路层详细信息，这些详细信息是在数据段上发送封装数据链路帧时指定其目的地所必需的。
The IP addressing scheme includes an option that allows the administrators to not assign any subnets to point-to-point links (links connecting only two devices and using protocols like PPP, SLIP, or HDLC for IP encapsulation). This is possible because the routers do not need next-hop identifiers on point-to-point links
IP寻址方案包括一个选项，允许管理员不将任何子网分配给点到点链路（仅连接两个设备的链路，并使用PPP、SLIP或HDLC等协议进行IP封装）。这是可能的，因为路由器在点到点链路上不需要下一跳标识符
(there is only one destination for any transmission), and an interface-independent IP address can be used as the source and destination. Using the unnumbered option for a point-to-point link essentially makes it a purely topological entity used only to reach other destinations.
（任何传输只有一个目的地），并且可以使用独立于接口的IP地址作为源和目的地。对点到点链接使用无编号选项实质上使其成为仅用于到达其他目的地的纯拓扑实体。
The idea is very simple: provide a configuration mechanism to inform the IGP that the circuit is type point-to-point, irrespective of the physical media type. For the IGP, this implies that it will send protocol packets with the appropriate point-to-point information, and it expects to receive protocol packets as they would be received on a point-to-point circuit. Over LAN media, the MAC header must contain the correct multicast MAC address to be received by the other side of the connection. For vLAN environments, the MAC header must also contain the proper vLAN ID.
想法非常简单：提供一种配置机制，告知IGP电路为点对点类型，与物理介质类型无关。对于IGP，这意味着它将发送具有适当的点到点信息的协议包，并且它期望接收协议包，就像它们在点到点电路上接收一样。在LAN介质上，MAC报头必须包含连接另一端接收的正确多播MAC地址。对于vLAN环境，MAC标头还必须包含正确的vLAN ID。
In order to allow LAN links used to connect only two routers to be treated as unnumbered point-to-point interfaces, the MAC address resolution and nexthop IP address issues need to be addressed.
为了允许仅用于连接两个路由器的LAN链路被视为未编号的点对点接口，需要解决MAC地址解析和nexthop IP地址问题。
This p2p-over-lan circuit extension for IS-IS is only concerned with pure IP routing and forwarding operation.
IS-IS的p2p over lan电路扩展只涉及纯IP路由和转发操作。
Since physically the circuit is a broadcast one, the IS-IS protocol packets need to have MAC addresses for this p2p-over-lan circuit. From a link-layer point of view, those packets are IS-IS LAN packets. The Multi-destination address including AllISs, AllL1ISs, and AllL2ISs, defined in [ISO10589], can be used for link-layer encapsulation; the use of AllISs is recommended.
由于电路在物理上是广播电路，is-is协议数据包需要具有该p2p over lan电路的MAC地址。从链路层的角度来看，这些数据包是IS-IS LAN数据包。[ISO10589]中定义的AllISs、AllL1ISs、AllL2ISs等多目的地址可用于链路层封装；建议使用AllISs。
The circuit needs to have IP address(es), and the p2p IS-IS Hello (IIH) over this circuit MUST include the IP interface address(es) as defined in [RFC1195]. The IPv4 address(es) included in the IIHs is either the IP address assigned to the interface in the case of a numbered interface or the interface-independent IP address in the case of an unnumbered interface. The IPv6 addresses are link-local IPv6 address(es) [RFC5308].
电路需要有IP地址，该电路上的p2p IS-IS Hello（IIH）必须包括[RFC1195]中定义的IP接口地址。IIHs中包含的IPv4地址是分配给接口的IP地址（如果是编号接口），或者是独立于接口的IP地址（如果是未编号接口）。IPv6地址是链路本地IPv6地址[RFC5308]。
OSPF and OSPFv3 [RFC5340] routers supporting the capabilities described herein should support an additional interface configuration parameter specifying the interface topology type. For a LAN (i.e., broadcast-capable) interface, the interface may be viewed as a
支持本文所述功能的OSPF和OSPFv3[RFC5340]路由器应支持指定接口拓扑类型的附加接口配置参数。对于LAN（即，支持广播的）接口，该接口可被视为
point-to-point interface. Both routers on the LAN will simply join the AllSPFRouters multicast group and send all OSPF packets with a destination address of AllSPFRouters. AllSPFRouters is 224.0.0.5 for OSPF and FF02::5 for OSPFv3. This is identical to operation over a physical point-to-point link as described in Sections 8.1 and 8.2 of [RFC2328].
点对点接口。LAN上的两个路由器都将简单地加入AllSPFRouters多播组，并发送目标地址为AllSPFRouters的所有OSPF数据包。OSPF的所有SPFROUTERS为224.0.0.5，OSPFv3的FF02:：5。这与[RFC2328]第8.1节和第8.2节所述的物理点对点链路上的操作相同。
Unlike a normal point-to-point IGP circuit, the IP nexthop for the routes using this p2p-over-lan circuit as an outbound interface is not optional. The IP nexthop address has to be a valid interface or internal address on the adjacent router. This address is used by a local router to obtain the MAC address for IP packet forwarding. The ARP process has to be able to resolve the internal IPv4 address used for the unnumbered p2p-over-lan circuits. For the ARP implementation (which checks that the subnet of the source address of the ARP request matches the local interface address), this check needs to be relaxed for the unnumbered p2p-over-lan circuits. The misconfiguration detection is handled by the IGPs and is described in Section 4.5. In the IPv6 case, the ND resolves the MAC for the link-local address on the p2p-over-lan circuit, which is part of the IPv6 neighbor discovery process [RFC4861].
与普通的点对点IGP电路不同，使用此p2p over lan电路作为出站接口的路由的IP nexthop不是可选的。IP nexthop地址必须是相邻路由器上的有效接口或内部地址。本地路由器使用该地址获取用于IP数据包转发的MAC地址。ARP进程必须能够解析用于未编号的p2p over lan电路的内部IPv4地址。对于ARP实现（检查ARP请求源地址的子网是否与本地接口地址匹配），对于未编号的p2p over lan电路，需要放松此检查。错误配置检测由IGPs处理，如第4.5节所述。在IPv6情况下，ND解析p2p over lan电路上链路本地地址的MAC，这是IPv6邻居发现过程的一部分[RFC4861]。
In more general cases, while p2p-over-lan circuit is used as an unnumbered link, other MAC address resolution mechanisms are needed for IP packet forwarding; for example, if link state IGP is not configured over this p2p-over-lan link, or if the mechanism described in Section 4.3 is not possible. The following techniques can be used to acquire the MAC address and/or the next-hop IP address of the remote device on an unnumbered point-to-point LAN link.
在更一般的情况下，虽然p2p-over-lan电路被用作无编号链路，但是IP分组转发需要其他MAC地址解析机制；例如，如果没有在该p2p over lan链路上配置链路状态IGP，或者如果第4.3节中描述的机制不可行。以下技术可用于在未编号的点到点LAN链路上获取远程设备的MAC地址和/或下一跳IP地址。
1. Static configuration. A router can be statically configured with the MAC address that should be used as the destination MAC address when sending data out of the interface.
1. 静态配置。路由器可以静态配置MAC地址，当从接口发送数据时，该地址应用作目标MAC地址。
2. MAC address gleaning. If a dynamic routing protocol is running between the routers connected to the link, the MAC address of the remote device can be taken from a data-link frame carrying a packet of the corresponding routing protocol.
2. MAC地址收集。如果动态路由协议在连接到链路的路由器之间运行，则远程设备的MAC地址可以从承载相应路由协议的分组的数据链路帧获取。
With this p2p-over-lan extension, the difference between a LAN and a point-to-point circuit can be made purely by configuration. It is important to implement the mechanisms for early detection of misconfiguration.
通过这种p2p over lan扩展，lan和点对点电路之间的区别完全可以通过配置来实现。重要的是实施早期发现错误配置的机制。
If the circuit is configured as the point-to-point type and receives LAN hello packets, the router MUST discard the incoming packets; if the circuit is a LAN type and receives point-to-point hello packets, it MUST discard the incoming packets. If the system ID or the router ID of an incoming hello packet does not match the system ID or the router ID for an established adjacency over a p2p-over-lan circuit, the packet MUST be discarded. Furthermore, if OSPF hello suppression (as described in [RFC1793]) is active for the adjacency, the hello suppression MUST be terminated for a period of RouterIntervalSeconds. After this interval, either the neighbor adjacency will time out and an adjacency may be formed with a neighbor with a different router ID, or hello suppression may be renegotiated. The implementation should offer logging and debugging information of the above events.
如果电路配置为点对点类型并接收LAN hello数据包，则路由器必须丢弃传入数据包；如果电路为LAN类型并接收点对点hello数据包，则必须丢弃传入数据包。如果传入hello数据包的系统ID或路由器ID与通过p2p over lan电路建立的邻接的系统ID或路由器ID不匹配，则必须丢弃该数据包。此外，如果OSPF hello抑制（如[RFC1793]中所述）对邻接处于活动状态，则hello抑制必须在RouterIntervalSeconds期间终止。在此间隔之后，邻居邻接将超时，并且可能与具有不同路由器ID的邻居形成邻接，或者可能重新协商hello抑制。实现应提供上述事件的日志记录和调试信息。
Both routers on a LAN must support the p2p-over-lan extension and both must have the LAN segment configured as a p2p-over-lan circuit for successful operation. Both routers SHOULD support at least one of the above listed methods for mapping IP addresses on the link to MAC address. If a proprietary method of IP address to MAC address resolution is used by one router, both routers must be capable of using the same method. Otherwise, the link should be configured as a standard LAN link, with traditional IGP LAN models used.
LAN上的两个路由器都必须支持p2p over LAN扩展，并且都必须将LAN段配置为p2p over LAN电路才能成功运行。两个路由器都应支持上述方法中的至少一种，用于将链路上的IP地址映射到MAC地址。如果一个路由器使用IP地址到MAC地址解析的专有方法，则两个路由器必须能够使用相同的方法。否则，应将链路配置为标准LAN链路，并使用传统IGP LAN型号。
While there is advantage to using this extension on the LANs that are connected back to back or only contain two routers, there are trade offs when modeling a LAN as multiple vLANs and using this extension since one does sacrifice the inherent scalability benefits of multi-access networks. In general, it will increase the link state database size, the amount of packets flooded, and the route calculation overhead.
虽然在背靠背连接或仅包含两个路由器的LAN上使用此扩展具有优势，但在将LAN建模为多个VLAN并使用此扩展时，存在权衡，因为这样做会牺牲多接入网络固有的可扩展性优势。通常，它会增加链路状态数据库的大小、被淹没的数据包数量和路由计算开销。
Deployment of the described technique brings noticeable benefits from the perspective of IP address usage: the network management and the router configuration. Note, however, that use of the IP unnumbered
所述技术的部署从IP地址使用的角度带来了显著的好处：网络管理和路由器配置。但是，请注意，IP的使用没有编号
option for point-to-point LAN links inherits the same problems as those present for serial links, i.e., not being able to ping or monitor a specific interface between routers.
点对点LAN链路的选项继承了与串行链路相同的问题，即不能ping或监视路由器之间的特定接口。
This document does not introduce any new security issues to IS-IS, OSPF, ARP, or ND. Implementations may have 'source address subnet checks' that need to be relaxed as described in Section 4.3. These are used to manage misconfigurations, not so much to secure ARP -- if an attacker would be attached to the LAN, (s)he could pick a subnet-wise correct address as well.
本文档不会给IS-IS、OSPF、ARP或ND带来任何新的安全问题。如第4.3节所述，实施可能需要放松“源地址子网检查”。这些用于管理错误配置，而不是保护ARP——如果攻击者连接到LAN，他也可以选择正确的子网地址。
If one router on a link thinks that a LAN should be either broadcast or p2p-over-lan, and the other router has a different opinion, the adjacencies will never form, as specified in Section 4.5. There are no fallbacks at either end to resolve the situation, except by a manual configuration change.
如果链路上的一个路由器认为一个LAN应该是广播的或p2p over LAN，而另一个路由器有不同的意见，那么邻接将永远不会形成，如第4.5节所述。除手动更改配置外，两端都没有解决此问题的备用方案。
The authors would like to acknowledge the following individuals (in alphabetical order by last name): Pedro Marques, Christian Martin, Danny McPherson, Ajay Patel, Jeff Parker, Tony Przygienda, Alvaro Retana, and Pekka Savola.
作者希望确认以下个人（按姓氏字母顺序）：佩德罗·马尔克斯、克里斯蒂安·马丁、丹尼·麦克弗森、阿杰·帕特尔、杰夫·帕克、托尼·普济吉恩达、阿尔瓦罗·雷塔纳和佩卡·萨沃拉。
[ISO10589] ISO, "Intermediate System to Intermediate System intra-domain routeing information exchange protocol for use in conjunction with the protocol for providing the connectionless-mode network service (ISO 8473)", International Standard 10589:2002, Second Edition, 2002.
[ISO10589]ISO，“与提供无连接模式网络服务协议（ISO 8473）一起使用的中间系统到中间系统域内路由信息交换协议”，国际标准10589:2002，第二版，2002年。
[RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and dual environments", RFC 1195, December 1990.
[RFC1195]Callon，R.，“OSI IS-IS在TCP/IP和双环境中的路由使用”，RFC 11951990年12月。
[RFC1793] Moy, J., "Extending OSPF to Support Demand Circuits", RFC 1793, April 1995.
[RFC1793]莫伊，J.，“扩展OSPF以支持需求电路”，RFC1793，1995年4月。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.
[RFC2328]Moy，J.，“OSPF版本2”，STD 54，RFC 2328，1998年4月。
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, September 2007.
[RFC4861]Narten，T.，Nordmark，E.，Simpson，W.，和H.Soliman，“IP版本6（IPv6）的邻居发现”，RFC 48612007年9月。
[RFC5308] Hopps, C., "Routing IPv6 with IS-IS", RFC 5308, October 2008.
[RFC5308]Hopps，C.，“使用IS-IS路由IPv6”，RFC5308，2008年10月。
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF for IPv6", RFC 5340, July 2008.
[RFC5340]Coltun，R.，Ferguson，D.，Moy，J.，和A.Lindem，“IPv6的OSPF”，RFC 53402008年7月。
Contributors
贡献者
The following individuals are the authors that contributed to the contents of this document.
以下个人是对本文件内容做出贡献的作者。
Acee Lindem Cisco Systems 7025 Kit Creek Road Research Triangle Park, NC 27709 USA EMail: acee@cisco.com
Acee Lindem Cisco Systems 7025 Kit Creek Road Research Triangle Park，NC 27709美国电子邮件：acee@cisco.com
Jenny Yuan Cisco Systems 225 West Tasman Drive San Jose, CA 95134 USA EMail: jenny@cisco.com
Jenny Yuan Cisco Systems 225美国加利福尼亚州圣何塞西塔斯曼大道95134电子邮件：jenny@cisco.com
Russ White Cisco Systems, Inc. 7025 Kit Creek Rd. Research Triangle Park, NC 27709 EMail: riw@cisco.com
Russ White Cisco Systems，Inc.地址：北卡罗来纳州三角研究园基特克里克路7025号邮编：27709电子邮件：riw@cisco.com
Stefano Previdi Cisco Systems, Inc. De Kleetlaan 6A 1831 Diegem - Belgium EMail: sprevidi@cisco.com
Stefano Previdi Cisco Systems，Inc.De Kleetlaan 6A 1831 Diegem-比利时电子邮件：sprevidi@cisco.com
Editors' Addresses
编辑地址
Naiming Shen Cisco Systems 225 West Tasman Drive San Jose, CA 95134 USA EMail: naiming@cisco.com
沈乃明思科系统225西塔斯曼大道圣何塞，加利福尼亚州95134美国电子邮件：naiming@cisco.com
Alex Zinin Alcatel-Lucent 750D Chai Chee Rd, #06-06 Technopark@ChaiChee Singapore 469004
Alex Zinin Alcatel-Lucent柴子路750D号#06-06Technopark@ChaiChee新加坡469004
EMail: alex.zinin@alcatel-lucent.com
EMail: alex.zinin@alcatel-lucent.com
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This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights.
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