Network Working Group S. Krishnan, Ed.
Request for Comments: 4957 Ericsson Research
Category: Informational N. Montavont
GET ENST Bretagne
E. Njedjou
France Telecom
S. Veerepalli
Qualcomm
A. Yegin, Ed.
Samsung
August 2007
Network Working Group S. Krishnan, Ed.
Request for Comments: 4957 Ericsson Research
Category: Informational N. Montavont
GET ENST Bretagne
E. Njedjou
France Telecom
S. Veerepalli
Qualcomm
A. Yegin, Ed.
Samsung
August 2007
Link-Layer Event Notifications for Detecting Network Attachments
用于检测网络附件的链路层事件通知
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。
Copyright Notice
版权公告
Copyright (C) The IETF Trust (2007).
版权所有（C）IETF信托基金（2007年）。
Abstract
摘要
Certain network access technologies are capable of providing various types of link-layer status information to IP. Link-layer event notifications can help IP expeditiously detect configuration changes. This document provides a non-exhaustive catalogue of information available from well-known access technologies.
某些网络接入技术能够向IP提供各种类型的链路层状态信息。链路层事件通知可以帮助IP快速检测配置更改。本文件提供了从知名接入技术获得的非详尽信息目录。
Table of Contents
目录
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Link-Layer Event Notifications . . . . . . . . . . . . . . . . 5
3.1. GPRS/3GPP . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2. cdma2000/3GPP2 . . . . . . . . . . . . . . . . . . . . . . 7
3.3. IEEE 802.11/WiFi . . . . . . . . . . . . . . . . . . . . . 8
3.4. IEEE 802.3 CSMA/CD . . . . . . . . . . . . . . . . . . . . 9
3.4.1. Link Integrity Tests in 802.3 Networks . . . . . . . . 10
3.4.2. IEEE 802.1D Bridging and Its Effects on Link-layer
Event Notifications . . . . . . . . . . . . . . . . . 11
3.4.3. 802.1AB Link-Layer Discovery Protocol . . . . . . . . 12
3.4.4. Other Heuristics . . . . . . . . . . . . . . . . . . . 13
3.4.5. Summary . . . . . . . . . . . . . . . . . . . . . . . 13
4. Security Considerations . . . . . . . . . . . . . . . . . . . 13
5. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 14
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
7.1. Normative References . . . . . . . . . . . . . . . . . . . 14
7.2. Informative References . . . . . . . . . . . . . . . . . . 16
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Link-Layer Event Notifications . . . . . . . . . . . . . . . . 5
3.1. GPRS/3GPP . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2. cdma2000/3GPP2 . . . . . . . . . . . . . . . . . . . . . . 7
3.3. IEEE 802.11/WiFi . . . . . . . . . . . . . . . . . . . . . 8
3.4. IEEE 802.3 CSMA/CD . . . . . . . . . . . . . . . . . . . . 9
3.4.1. Link Integrity Tests in 802.3 Networks . . . . . . . . 10
3.4.2. IEEE 802.1D Bridging and Its Effects on Link-layer
Event Notifications . . . . . . . . . . . . . . . . . 11
3.4.3. 802.1AB Link-Layer Discovery Protocol . . . . . . . . 12
3.4.4. Other Heuristics . . . . . . . . . . . . . . . . . . . 13
3.4.5. Summary . . . . . . . . . . . . . . . . . . . . . . . 13
4. Security Considerations . . . . . . . . . . . . . . . . . . . 13
5. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 14
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
7.1. Normative References . . . . . . . . . . . . . . . . . . . 14
7.2. Informative References . . . . . . . . . . . . . . . . . . 16
It is not an uncommon occurrence for a node to change its point of attachment to the network. This can happen due to mobile usage (e.g., a mobile phone moving among base stations) or nomadic usage (e.g., road-warrior case).
节点更改其网络连接点的情况并不少见。这可能是由于移动使用（例如，移动电话在基站之间移动）或游牧使用（例如，road warrior案例）造成的。
A node changing its point of attachment to the network may end up changing its IP subnet and therefore require reconfiguration of IP-layer parameters, such as IP address, default gateway information, and DNS server address. Detecting the subnet change can usually use network-layer indications (such as a change in the advertised prefixes for IPv6). But such indications may not be always available (e.g., Detecting Network Attachment in IPv6 (DNAv6)) to the node upon changing its point of attachment.
更改其网络连接点的节点可能最终更改其IP子网，因此需要重新配置IP层参数，例如IP地址、默认网关信息和DNS服务器地址。检测子网更改通常可以使用网络层指示（例如IPv6播发前缀的更改）。但是，在改变节点的连接点时，这种指示可能并不总是对节点可用（例如，在IPv6（DNAv6）中检测网络连接）。
Link-layer event notifications can help IP expeditiously detect configuration changes. This document provides a non-exhaustive catalog of information available from some access technologies, and discusses the interpretation of this information at the IP layer. This document is not intended to specify or change the behavior of these access technologies in any manner.
链路层事件通知可以帮助IP快速检测配置更改。本文档提供了一些访问技术提供的信息的非详尽目录，并讨论了在IP层对这些信息的解释。本文档无意以任何方式指定或更改这些访问技术的行为。
Additional information can be conveyed along with the event, such as the identifier of the network attachment point (e.g., IEEE 802.11 Basic Service Set Identification (BSSID) and Service Set Identifier (SSID)), or network-layer configuration parameters obtained via the link-layer attachment process if available. It is envisaged that such event notifications can in certain circumstances be used to expedite the inter-subnet movement detection and reconfiguration process. For example, the notification indicating that the node has established a new link-layer connection may be used for immediately probing the network for a possible configuration change. In the absence of such a notification from the link layer, IP has to wait for indications that are not immediately available, such as receipt of the next scheduled router advertisement, unreachability of the default gateway, etc.
附加信息可以随事件一起传送，例如网络连接点的标识符（例如，IEEE 802.11基本服务集标识（BSSID）和服务集标识符（SSID）），或者通过链路层连接过程获得的网络层配置参数（如果可用）。设想在某些情况下，此类事件通知可用于加快子网间移动检测和重新配置过程。例如，指示节点已建立新链路层连接的通知可用于立即探测网络以获得可能的配置更改。在没有来自链路层的这种通知的情况下，IP必须等待不立即可用的指示，例如接收到下一个调度的路由器广告、无法访问默认网关等。
It should be noted that a link-layer event notification does not always translate into a subnet change. Even if the node has torn down a link-layer connection with one attachment point and established a new connection with another, it may still be attached to the same IP subnet. For example, several IEEE 802.11 access points can be attached to the same IP subnet. Moving among these access points does not warrant any IP-layer configuration change.
应该注意的是，链路层事件通知并不总是转换为子网更改。即使节点已断开与一个连接点的链路层连接并与另一个连接点建立了新连接，它仍可能连接到同一IP子网。例如，多个IEEE 802.11接入点可以连接到同一IP子网。在这些接入点之间移动并不保证任何IP层配置更改。
In order to enable an enhanced scheme for detecting change of subnet, we need to define link-layer event notifications that can be realistically expected from various access technologies. The objective of this document is to provide a catalogue of link-layer events and notifications in various architectures. While this document mentions the utility of this information for detecting change of subnet (or, detecting network attachment - DNA), the detailed usage is left to other documents, namely, DNA solution specifications.
为了实现检测子网变化的增强方案，我们需要定义链路层事件通知，这些通知可以从各种访问技术中实际预期。本文档的目的是提供各种体系结构中链路层事件和通知的目录。虽然本文档提到了该信息在检测子网变化（或检测网络连接-DNA）方面的实用性，但详细用法留给其他文档，即DNA解决方案规范。
The document limits itself to the minimum set of information that is necessary for solving the DNA problem [RFC4135]. A broader set of information (e.g., signal strength, packet loss, etc.) and events (e.g. link down) may be used for other problem spaces, such as anticipation-based Mobile IP fast handovers [RFC4881], [RFC4068], etc.
该文件仅限于解决DNA问题所需的最小信息集[RFC4135]。更广泛的信息集（例如，信号强度、分组丢失等）和事件（例如，链路断开）可用于其他问题空间，例如基于预期的移动IP快速切换[RFC4881]、[RFC4068]等。
These event notifications are considered with hosts in mind, although they may also be available on the network side (e.g., on the access points and routers). An API or protocol-based standard interface may be defined between the link layer and IP for conveying this information. That activity is beyond the scope of this document.
虽然这些事件通知也可能在网络端（例如，在接入点和路由器上）可用，但在考虑主机时会考虑这些事件通知。可以在链路层和IP之间定义基于API或协议的标准接口，用于传输该信息。该活动超出了本文件的范围。
Link: is a communication facility or medium over which network nodes can communicate. Each link is associated with a minimum of two endpoints. An "attachment point" is the link endpoint on the link to which the node is currently connected, such as an access point, a base station, or a wired switch.
链路：是网络节点可以通过其进行通信的通信设施或媒介。每个链接至少与两个端点关联。“连接点”是节点当前连接到的链路上的链路端点，例如接入点、基站或有线交换机。
Link up: is an event provided by the link layer that signifies a state change associated with the interface becoming capable of communicating data packets. This event is associated with a link-layer connection between the node and an attachment point.
链接：是由链接层提供的事件，表示与接口相关的状态改变，从而能够传输数据包。此事件与节点和附着点之间的链接层连接关联。
BSSID: Basic Service Set Identification
BSSID：基本服务集标识
DNA: Detecting Network Attachment
DNA：检测网络连接
GPRS: General Packet Radio Service
通用分组无线业务
PDP: Packet Data Protocol
分组数据协议
SSID: Service Set Identifier
SSID：服务集标识符
Link-layer event notifications are considered to be one of the inputs to the DNA process. A DNA process is likely to take other inputs (e.g., presence of advertised prefixes, reachability of default gateways) before determining whether IP-layer configuration must be updated. It is expected that the DNA process can take advantage of link-layer notifications when they are made available to IP. While by itself a link-layer notification may not constitute all the input DNA needs, it can at least be useful for prompting the DNA process to collect further information (i.e., other inputs to the process). For example, the node may send a router solicitation as soon as it learns that a new link-layer connection is established.
链路层事件通知被认为是DNA过程的输入之一。在确定是否必须更新IP层配置之前，DNA过程可能会接受其他输入（例如，广告前缀的存在、默认网关的可达性）。当链接层通知提供给IP时，预计DNA进程可以利用这些通知。虽然链路层通知本身可能并不构成所有输入DNA需求，但它至少可用于提示DNA过程收集进一步信息（即，过程的其他输入）。例如，一旦节点获悉建立了新的链路层连接，它就可以发送路由器请求。
The link-layer event that is considered most useful to DNA process is the link up event. The associated notifications can be provided to the IP-layer after the event concludes successfully. The link up events and notifications are associated with a network interface on the node. The IP module may receive simultaneous independent notifications from each one of the network interfaces on the node.
被认为对DNA过程最有用的链路层事件是链路连接事件。事件成功结束后，可以向IP层提供相关通知。链接事件和通知与节点上的网络接口相关联。IP模块可以从节点上的每个网络接口同时接收独立的通知。
The actual event is managed by the link layer of the node through execution of link-layer protocols and mechanisms. Once the event successfully completes within the link layer, its notification is delivered to the IP-layer. By the time the notification is delivered, the link layer of the node must be ready to accept IP packets from the IP and the physical layers. Each time an interface changes its point of attachment, a link up event should be generated.
实际事件由节点的链路层通过执行链路层协议和机制来管理。一旦事件在链路层内成功完成，其通知将传递到IP层。在发送通知时，节点的链路层必须准备好接受来自IP和物理层的IP数据包。每次接口更改其连接点时，都应生成一个链接事件。
There is a non-deterministic usage of the link up notification to accommodate implementations that desire to indicate the link is up, but the data transmission may be blocked in the network (see IEEE 802.3 discussion). A link up notification may be generated with an appropriate attribute, conveying its non-deterministic nature, to convey the event. Alternatively, the link-layer implementation may choose to delay the link up notification until the risk conditions cease to exist.
链路接通通知的使用是不确定的，以适应希望指示链路接通的实现，但是数据传输可能在网络中被阻断（参见IEEE 802.3讨论）。可使用适当的属性生成链接通知，传达其非确定性性质，以传达事件。或者，链路层实现可以选择延迟链路通知，直到风险条件不再存在。
If a non-deterministic link up was generated, another link up must follow as soon as the link layer is capable of generating a deterministic notification. The event attributes may indicate whether the packets transmitted since the previous notification were presumed to be blocked or allowed by the network, if the link layer could determine the exact conditions.
如果生成了非确定性链接，则一旦链接层能够生成确定性通知，则必须立即执行另一个链接。如果链路层能够确定确切的条件，则事件属性可以指示自先前通知以来发送的分组是否被假定为被网络阻止或允许。
The deterministic link up event following a non-deterministic link up event can be treated differently by consumers of the link up event. For example, the second link up event need not trigger a confirmation process, if the first one already did.
非确定性链接事件之后的确定性链接事件可以由链接事件的使用者进行不同的处理。例如，如果第一个链接事件已经触发了确认过程，则第二个链接事件不需要触发确认过程。
A node may have to change its IP-layer configuration even when the link-layer connection stays the same. An example scenario is the IPv6 subnet renumbering [RFC2461]. Therefore, there exist cases where IP-layer configuration may have to change even without the IP layer receiving a link up notification. Therefore, a link-layer notification is not a mandatory indication of a subnet change.
即使链路层连接保持不变，节点也可能必须更改其IP层配置。一个示例场景是IPv6子网重新编号[RFC2461]。因此，在某些情况下，即使IP层没有收到连接通知，IP层配置也可能必须更改。因此，链路层通知不是子网更改的强制指示。
A link up notification may optionally deliver information relating to the attachment point. Such auxiliary information may include the identity of the attachment point (e.g., base station identifier), or the IP-layer configuration parameters associated with the attached subnet (e.g., subnet prefix, default gateway address, etc.). While merely knowing that a new link-layer connection is established may prompt the DNA process to immediately seek other clues for detecting a network configuration change, auxiliary information may constitute further clues (and even the final answers sometimes). In cases where there is a one-to-one mapping between the attachment point identifiers and the IP-layer configurations, learning the former can reveal the latter. Furthermore, IP-layer configuration parameters obtained during the link-layer connection may be exactly what the DNA process is trying to discover.
链接通知可以选择性地传递与连接点相关的信息。此类辅助信息可包括连接点的标识（例如，基站标识符）或与连接子网相关联的IP层配置参数（例如，子网前缀、默认网关地址等）。虽然仅仅知道建立了新的链路层连接可能会促使DNA过程立即寻找其他线索来检测网络配置的变化，但辅助信息可能构成进一步的线索（有时甚至是最终答案）。在连接点标识符和IP层配置之间存在一对一映射的情况下，学习前者可以揭示后者。此外，在链路层连接期间获得的IP层配置参数可能正是DNA过程试图发现的。
The link-layer process leading to a link up event depend on the link technology. While a link-layer notification must always indicate that the link up event occurred, the availability and types of auxiliary information on the attachment point depends on the link-layer technology as well. The following subsections examine four link-layer technologies and describe when a link-layer notification is generated and what information is included in it.
导致链接事件的链接层过程取决于链接技术。虽然链路层通知必须始终指示发生了链接事件，但连接点上辅助信息的可用性和类型也取决于链路层技术。以下小节将研究四种链接层技术，并描述何时生成链接层通知以及其中包含哪些信息。
GSM Packet Radio System (GPRS) provides packet-switched data transmission over a cellular network [GPRS][GPRS-LINK].
GSM分组无线系统（GPRS）通过蜂窝网络提供分组交换数据传输[GPRS][GPRS-LINK]。
The GPRS architecture consists of a Radio Access Network and a packet domain Core Network.
GPRS体系结构由无线接入网络和分组域核心网络组成。
- The GPRS Radio Access Network is composed of Mobile Terminals (MTs), a Base Station Subsystem and Serving GPRS Support Nodes (SGSNs).
- GPRS无线接入网络由移动终端（MTs）、基站子系统和服务GPRS支持节点（SGSN）组成。
- An IP Core Network that acts as the transport backbone of user datagrams between SGSNs and Gateway GPRS Support Nodes (GGSNs). The GGSN ensures the GPRS IP core network connectivity with external networks, such as the Internet or Local Area Networks. The GGSN acts as the default IP gateway for the MT.
- 作为SGSN和网关GPRS支持节点（GGSN）之间用户数据报传输骨干的IP核心网络。GGSN确保GPRS IP核心网络与外部网络（如Internet或局域网）的连接。GGSN充当MT的默认IP网关。
A GPRS MT that wants to establish IP connectivity establishes first a connection to the GPRS network and one or more PDP Context associations between the MT and the GGSN. It is only after the PDP Context has been established and after address autoconfiguration and tunneling mechanism have taken place that the MT's IP packets can be forwarded to and from its remote IP peers. The aim of PDP Context establishment is also to provide IP-level configuration on top of the GPRS link-layer attachment.
要建立IP连接的GPRS MT首先建立到GPRS网络的连接，并在MT和GGSN之间建立一个或多个PDP上下文关联。只有在PDP上下文建立之后，并且在地址自动配置和隧道机制发生之后，MT的IP数据包才能转发到其远程IP对等方或从其远程IP对等方转发。PDP上下文建立的目的也是在GPRS链路层连接上提供IP级配置。
Successful establishment of a PDP Context on a GPRS link signifies the availability of IP service to the MT. Therefore, this link-layer event generates a link up event notification sent to the IP layer.
在GPRS链路上成功建立PDP上下文表示MT的IP服务可用。因此，此链路层事件将生成发送到IP层的链接事件通知。
An MT may establish a secondary PDP Context while reusing the IP configuration acquired from a previously established and active PDP Context. Such a secondary PDP Context does not provide additional information to the IP layer and only allows another quality-of-service (QoS) profile to be used. The activation of such a secondary PDP context does not usually generate a link up event since it does not require new IP parameters. However, other additional PDP Context activations are to be treated as indicated earlier.
MT可以在重用从先前建立的和活动的PDP上下文获取的IP配置的同时建立辅助PDP上下文。这样的次要PDP上下文不向IP层提供额外信息，只允许使用另一个服务质量（QoS）概要文件。激活此类辅助PDP上下文通常不会生成链接事件，因为它不需要新的IP参数。但是，其他附加PDP上下文激活将按照前面所述进行处理。
With IPv4, the auxiliary information carried along with this notification is the IPv4 address of the MT that is obtained as part of the PDP Context. With IPv6, the PDP Context activation response does not come along with a usable IPv6 address. Effectively, the IPv6 address received from the GGSN in the PDP address field of the message does not contain a valid prefix. The MN actually only uses the interface identifier extracted from that field to form a link-local address that it uses afterwards to obtain a valid prefix (e.g., by stateless [RFC2462][GPRS-CN] or stateful [RFC3315] [GPRS-GSSA] address configuration). Therefore, no IPv6-related auxiliary information is provided to the IP layer.
对于IPv4，此通知附带的辅助信息是作为PDP上下文的一部分获得的MT的IPv4地址。对于IPv6，PDP上下文激活响应不会附带可用的IPv6地址。实际上，从消息的PDP地址字段中的GGSN接收的IPv6地址不包含有效前缀。MN实际上仅使用从该字段提取的接口标识符来形成链路本地地址，随后使用该地址来获得有效前缀（例如，通过无状态[RFC2462][GPRS-CN]或有状态[RFC3315][GPRS-GSSA]地址配置）。因此，没有向IP层提供与IPv6相关的辅助信息。
cdma2000-based 3GPP2 packet data services provide mobile users wide area high-speed access to packet switched networks [CDMA2K]. Some of the major components of the 3GPP2 packet network architecture consist of:
基于cdma2000的3GPP2分组数据业务为移动用户提供对分组交换网络[CDMA2K]的广域高速接入。3GPP2分组网络架构的一些主要组件包括：
- Mobile Station (MS), which allows mobile access to packet-switched networks over a wireless connection.
- 移动站（MS），允许通过无线连接移动访问分组交换网络。
- Radio Access Network, which consists of the Base Station Transceivers, Base Station Controllers, and the Packet Control Function.
- 无线接入网，由基站收发器、基站控制器和分组控制功能组成。
- Network Access Server known as the Packet Data Switching Node (PDSN). The PDSN also serves as default IP gateway for the IP MS.
- 网络访问服务器称为分组数据交换节点（PDSN）。PDSN还用作IP MS的默认IP网关。
3GPP2 networks use the Point-to-Point Protocol (PPP [RFC1661]) as the link-layer protocol between the MS and the PDSN. Before any IP packets may be sent or received, PPP must reach the Network-Layer Protocol phase, and the IP Control Protocol (IPCP [RFC1332], IPV6CP [RFC2472]) must reach the Opened state. When these states are reached in PPP, a link up event notification is delivered to the IP layer.
3GPP2网络使用点对点协议（PPP[RFC1661]）作为MS和PDSN之间的链路层协议。在发送或接收任何IP数据包之前，PPP必须达到网络层协议阶段，并且IP控制协议（IPCP[RFC1332]，IPV6CP[RFC2472]）必须达到打开状态。当PPP中达到这些状态时，将向IP层发送链接事件通知。
When the PPP is used for 3GPP2 Simple (i.e., non-Mobile) IPv4 Service, IPCP enables configuration of an IPv4 address on the MS. This IPv4 address is provided as the auxiliary information along with the link up notification. IPV6CP used for Simple IPv6 service does not provide an IPv6 address, but the interface identifiers for local and remote endpoints of the PPP link. Since there is no standards-mandated correlation between the interface identifier and other IP-layer configuration parameters, this information is deemed not useful for DNA (nevertheless, it may be provided as auxiliary information for other uses).
当PPP用于3GPP2简单（即非移动）IPv4服务时，IPCP允许在MS上配置IPv4地址。此IPv4地址作为辅助信息与链接通知一起提供。用于简单IPv6服务的IPV6CP不提供IPv6地址，但提供PPP链路的本地和远程端点的接口标识符。由于接口标识符和其他IP层配置参数之间没有标准规定的相关性，因此该信息被认为对DNA没有用处（尽管如此，它可以作为其他用途的辅助信息提供）。
IEEE 802.11-based WiFi networks are the wireless extension of the Local Area Networks. Currently available standards are IEEE 802.11b [IEEE-802.11b], IEEE 802.11g [IEEE-802.11g], and IEEE 802.11a [IEEE-802.11a]. The specifications define both the MAC layer and the physical layer. The MAC layer is the same for all these technologies.
基于IEEE 802.11的WiFi网络是局域网的无线扩展。目前可用的标准有IEEE 802.11b[IEEE-802.11b]、IEEE 802.11g[IEEE-802.11g]和IEEE 802.11a[IEEE-802.11a]。规范定义了MAC层和物理层。所有这些技术的MAC层都是相同的。
Two operating modes are available in the IEEE 802.11 series, either infrastructure mode or ad-hoc mode. In infrastructure mode, all link-layer frames are transmitted to an access point (AP) that then forwards them to the final receiver. A station (STA) establishes an IEEE 802.11 association with an AP in order to send and receive IP packets. In a WiFi network that uses Robust Secure Network (RSN [IEEE-802.11i]), successful completion of the 4-way handshake between the STA and AP commences the availability of IP service. The link up
IEEE 802.11系列中有两种操作模式，即基础设施模式或自组织模式。在基础设施模式下，所有链路层帧都被传输到接入点（AP），然后接入点（AP）将它们转发到最终接收器。站点（STA）与AP建立IEEE 802.11关联，以便发送和接收IP分组。在使用健壮安全网络（RSN[IEEE-802.11i]）的WiFi网络中，成功完成STA和AP之间的4路握手开始IP服务的可用性。连接
event notification is generated upon this event. In non-RSN-based networks, successful association or re-association events on the link layer causes a link up notification sent to the IP layer.
事件通知在发生此事件时生成。在非基于RSN的网络中，链路层上的成功关联或重新关联事件会导致向IP层发送链接通知。
As part of the link establishment, the STA learns the BSSID and SSID associated with the AP. The BSSID is a unique identifier of the AP, usually set to the MAC address of the wireless interface of the AP. The SSID carries the identifier of the Extended Service Set (ESS) -- the set composed of APs and associated STAs that share a common distribution system. The BSSID and SSID may be provided as auxiliary information along with the link up notification. Unfortunately, this information does not provide a deterministic indication of whether the IP-layer configuration must be changed upon movement. There is no standards-mandated one-to-one relation between the BSSID/SSID pairs and IP subnets. An AP with a given BSSID can connect a STA to any one of multiple IP subnets. Similarly, an ESS with the given SSID may span multiple IP subnets. And finally, the SSIDs are not globally unique. The same SSID may be used by multiple independent ESSs. Nevertheless, BSSID/SSID information may be used in a probabilistic way by the DNA process; hence, it is provided with the link up event notification.
作为链路建立的一部分，STA学习与AP相关联的BSSID和SSID。BSSID是AP的唯一标识符，通常设置为AP无线接口的MAC地址。SSID携带扩展服务集（ESS）的标识符——该集由AP和共享公共分发系统的关联STA组成。BSSID和SSID可以与链接通知一起作为辅助信息提供。不幸的是，该信息并不能确定是否必须在移动时更改IP层配置。BSSID/SSID对和IP子网之间没有标准强制的一对一关系。具有给定BSSID的AP可以将STA连接到多个IP子网中的任何一个。类似地，具有给定SSID的ESS可以跨越多个IP子网。最后，SSID不是全局唯一的。多个独立的ESS可以使用相同的SSID。然而，BSSID/SSID信息可通过DNA过程以概率方式使用；因此，它提供了链接事件通知。
In ad-hoc mode, mobile stations (STA) in range may directly communicate with each other, i.e., without any infrastructure or intermediate hop. The set of communicating STAs is called IBSS for Independent Basic Service Set. In an IBSS, only STA services are available, i.e., authentication, deauthentication, privacy, and MAC Service Data Unit (MSDU) delivery. STAs do not associate with each other, and therefore may exchange data frames in state 2 (authenticated and not associated) or even in state 1 (unauthenticated and unassociated) if the Distribution System is not used (i.e., "To DS" and "From DS" bits are clear). If authentication is performed, a link up indication can be generated upon authentication. Concerning the link layer identification, both the BSSID (which is a random MAC address chosen by a STA of the IBSS) and SSID may be used to identify a link, but not to make any assumptions on the IP network configuration.
在自组织模式下，范围内的移动站（STA）可以彼此直接通信，即，不需要任何基础设施或中间跳。对于独立的基本服务集，通信STA集称为IBSS。在IBSS中，只有STA服务可用，即身份验证、反身份验证、隐私和MAC服务数据单元（MSDU）交付。STA彼此不关联，因此，如果未使用分发系统（即，“至DS”和“自DS”位为空），STA可以在状态2（已验证且未关联）甚至状态1（未验证且未关联）下交换数据帧。如果执行了身份验证，则可以在身份验证时生成链接指示。关于链路层标识，BSSID（它是由ibs的STA选择的随机MAC地址）和SSID都可用于标识链路，但不用于对IP网络配置进行任何假设。
IEEE 802.3 CSMA/CD (commonly referred to as Ethernet) is the most commonly deployed Local Area Network technology in use today. As deployed today, it is specified by a physical layer/medium access control (MAC) layer specification [IEEE-802.3]. In order to provide connection of different LANs together into a larger network, 802.3 LANs are often bridged together [IEEE-802.1D].
IEEE 802.3 CSMA/CD（通常称为以太网）是目前使用的最常用的局域网技术。正如今天部署的一样，它由物理层/媒体访问控制（MAC）层规范[IEEE-802.3]指定。为了将不同的局域网连接到一个更大的网络中，802.3局域网通常桥接在一起[IEEE-802.1D]。
In this section, the terms 802.3 and Ethernet are used interchangeably. This section describes some issues in providing link-layer indications on Ethernet networks, and shows how bridging affects these indications.
在本节中，术语802.3和以太网可互换使用。本节介绍在以太网网络上提供链路层指示的一些问题，并说明桥接如何影响这些指示。
In Ethernet networks, hosts are connected by wires or by optic fibre to a switch (bridge), a bus (e.g., coaxial cable), a repeater (hub), or directly to another Ethernet device. Interfaces are symmetric, in that while many different physical layers may be present, medium access control is uniform for all devices.
在以太网网络中，主机通过电线或光纤连接到交换机（网桥）、总线（如同轴电缆）、中继器（集线器），或直接连接到另一个以太网设备。接口是对称的，因为虽然可能存在许多不同的物理层，但所有设备的介质访问控制是统一的。
In order to determine whether the physical medium is ready for frame transfer, IEEE 802.3 Ethernet specifies its own link monitoring mechanism, which is defined for some, but not all, classes of media. Where available, this Link Integrity Test operation is used to identify when packets are able to be received on an Ethernet segment. It is applicable to both wired and optical physical layers, although details vary between technologies (link pulses in twisted pair copper, light levels in fibre).
为了确定物理介质是否已准备好进行帧传输，IEEE 802.3以太网指定了自己的链路监控机制，该机制是为某些（但不是所有）介质类别定义的。在可用的情况下，此链路完整性测试操作用于确定何时能够在以太网段上接收数据包。它既适用于有线物理层，也适用于光学物理层，尽管不同技术的细节有所不同（双绞线铜缆中的链路脉冲、光纤中的光级）。
Link Integrity Tests in 802.3 networks typically occur at initial physical connection time (for example, at the auto-negotiation stage) and periodically afterwards. They make use of physical-layer specific operations to determine if a medium is able to support link-layer frames [IEEE-802.3].
802.3网络中的链路完整性测试通常在初始物理连接时（例如，在自动协商阶段）进行，然后定期进行。它们利用物理层特定的操作来确定介质是否能够支持链路层帧[IEEE-802.3]。
The status of the link as determined by the Link Integrity Test is stored in the variable 'link_status'. Changes to the value of link_status (for example due to Link Integrity Test failure) will generate link indications if the technology-dependent interface is implemented on an Ethernet device [IEEE-802.3].
链路完整性测试确定的链路状态存储在变量“link_status”中。如果技术相关接口在以太网设备上实现[IEEE-802.3]，对链路_状态值的更改（例如，由于链路完整性测试失败）将生成链路指示。
The link_status has possible values of FAIL, READY, and OK. In FAIL state, Link Integrity Tests have failed. In READY state, the link segment has passed integrity tests, but auto-negotiation has not completed. In OK state, the medium is able to send and receive packets.
链路_状态可能有FAIL、READY和OK值。在失败状态下，链路完整性测试失败。在就绪状态下，链接段已通过完整性测试，但自动协商尚未完成。在OK状态下，媒体能够发送和接收数据包。
Upon transition to a particular state, the Physical Medium Attachment subsystems generates a PMA_LINK.indicate(link_status). Indications of OK state may be used to generate a link up event notification. These indications do not definitively ensure that packets will be able to be received through the bridge domain, though (see the next section). Such operations are governed by bridging.
在转换到特定状态时，物理介质连接子系统生成PMA_链路。指示（链路_状态）。OK状态指示可用于生成连接事件通知。但是，这些指示并不能最终确保数据包能够通过网桥域接收（请参阅下一节）。此类操作由桥接控制。
3.4.2. IEEE 802.1D Bridging and Its Effects on Link-layer Event Notifications
3.4.2. IEEE 802.1D桥接及其对链路层事件通知的影响
Ethernet networks commonly consist of LANs joined together by transparent bridges (usually implemented as switches). Transparent bridges require the active topology to be loop free. This is achieved through the Spanning Tree Protocol (STP) or the Rapid Spanning Tree Protocol (RSTP). These protocols exchange Bridge Protocol Data Units (BPDUs), as defined in [IEEE-802.1D]; this leads to the blocking of ports (i.e., not forwarding), where required.
以太网网络通常由由透明网桥（通常作为交换机实现）连接在一起的局域网组成。透明网桥要求活动拓扑是无环的。这是通过生成树协议（STP）或快速生成树协议（RSTP）实现的。这些协议交换[IEEE-802.1D]中定义的网桥协议数据单元（BPDU）；这会在需要时导致端口阻塞（即不转发）。
By default, the spanning tree protocol does not know whether a particular newly connected piece of Ethernet will cause a loop.
默认情况下，生成树协议不知道某个新连接的以太网是否会导致循环。
Therefore, it will block all traffic from and to newly connected ports with the exception of some unbridged management frames. The STP will determine if the port can be connected to the network in a loop-free manner.
因此，除了一些未桥接的管理框架外，它将阻止所有来自和到新连接端口的流量。STP将确定端口是否可以以无环路方式连接到网络。
For these technologies, even though the link layer appears available, no data packet forwarding will occur until it is determined that the port can be connected to the network in a loop-free environment.
对于这些技术，即使链路层看起来可用，在确定端口可以在无环路环境中连接到网络之前，不会发生数据包转发。
For hosts that are providing indications to upper-layer protocols, even if the host itself does not implement bridging or STP, packet delivery across the network can be affected by the presence of bridges.
对于向上层协议提供指示的主机，即使主机本身没有实现桥接或STP，网桥的存在也会影响网络上的数据包交付。
A host connected to a bridge port does not receive any explicit indication that the bridge has started forwarding packets. Therefore, a host may not know when STP operations have completed, or when it is safe to inform upper layers to transmit packets.
连接到网桥端口的主机未接收到网桥已开始转发数据包的任何明确指示。因此，主机可能不知道STP操作何时完成，或者何时通知上层传输数据包是安全的。
Where it is not known that forwarding operations are available, a host should assume that RSTP or STP is being performed. Hosts may listen to STP/RSTP and 802.1AB messages to gain further information about the timing of full connectivity on the link, for example, to override an existing indication.
在不知道转发操作可用的情况下，主机应假定正在执行RSTP或STP。主机可以侦听STP/RSTP和802.1AB消息，以获得关于链路上完全连接的时间的进一步信息，例如，覆盖现有指示。
Notably, though, it is not easy for a host to distinguish between disabled bridge ports and non-bridge ports with no active transmitters on them, as Disabled ports will have no traffic on them, and incur 100% sender loss.
但值得注意的是，主机很难区分禁用的网桥端口和没有活动发射机的非网桥端口，因为禁用的端口上没有通信量，并且会导致100%的发送方丢失。
If no bridge configuration messages are received within the Bridge_Max_Age interval (default 20s) then it is likely that there is no visible bridge whose port is enabled for bridging (S8.4.5 of [IEEE-802.1D]), since at least two BPDU hello messages would have
如果在桥接器最大使用时间间隔（默认为20秒）内未接收到桥接器配置消息，则可能不存在端口已启用桥接的可见桥接器（IEEE-802.1D中的S8.4.5），因为至少有两条BPDU hello消息
been lost. Upon this timeout, a link up notification is generated, if one has not been already.
我迷路了。在此超时后，如果尚未生成链接通知，则会生成链接通知。
If a BPDU is received, and the adjacent bridge is running the original Spanning Tree Protocol, then a host cannot successfully send packets until at least twice the ForwardDelay value in the received BPDU has elapsed. After this time, a link up notification is generated. If the previous link up notification was non-deterministic, then this notification includes an attribute signifying that the packets sent within the prior interval were lost.
如果接收到BPDU，并且相邻网桥正在运行原始生成树协议，则主机无法成功发送数据包，直到接收到的BPDU中的ForwardDelay值超过至少两倍。在此时间之后，将生成一个链接通知。如果先前的链接通知是不确定的，则此通知包含一个属性，表示在先前间隔内发送的数据包丢失。
If the bridge is identified as performing Rapid Spanning Tree Protocol (RSTP), it instead waits Bridge_Max_Age after packet reception (advertised in the BPDU's Max Age field), before forwarding. For ports which are known to be point-to-point through auto-negotiation, this delay is abbreviated to 3 seconds after auto-negotiation completes [IEEE-802.1D].
如果网桥被识别为正在执行快速生成树协议（RSTP），那么它将在数据包接收后（在BPDU的最大年龄字段中公布）等待网桥最大年龄，然后再转发。对于已知通过自动协商实现点对点的端口，此延迟在自动协商完成后缩短为3秒[IEEE-802.1D]。
The recently defined 802.1AB Link-Layer Discovery Protocol (LLDP) provides information to devices that are directly adjacent to them on the local LAN [IEEE-802.1ab].
最近定义的802.1AB链路层发现协议（LLDP）为本地LAN上与其直接相邻的设备提供信息[IEEE-802.1AB]。
LLDP sends information periodically and at link status change time to indicate the configuration parameters of the device. Devices may send or receive these messages, or do both.
LLDP在链路状态更改时定期发送信息，以指示设备的配置参数。设备可以发送或接收这些消息，也可以同时发送或接收这两种消息。
The LLDP message may contain a System Capabilities TLV, which describes the MAC- and IP-layer functions that a device is currently using. Where a host receives the System Capabilities TLV indicating that no Bridging is occurring on the LLDP transmitter, no delays for STP calculation will be applied to packets sent through this transmitter. This would allow the generation of a link up notification.
LLDP消息可能包含系统功能TLV，描述设备当前使用的MAC层和IP层功能。如果主机接收到系统功能TLV，表明LLDP发送器上未发生桥接，则STP计算的延迟不会应用于通过该发送器发送的数据包。这将允许生成链接通知。
Additionally, if a host receives a System Capabilities TLV indicating that the LLDP transmitter is a bridge, the host's advertisement that it is an (end-host) Station-Only may tell the bridge not to run STP and may immediately allow forwarding.
此外，如果主机接收到指示LLDP发送器是网桥的系统能力TLV，则主机关于它是（终端主机）站的通告可能会告诉网桥不要运行STP，并且可能会立即允许转发。
Proprietary extensions may also indicate that data forwarding is already available on such a port. Discussion of such optimizations is out of scope for this document.
专有扩展还可能表明数据转发已经在这样的端口上可用。关于此类优化的讨论超出了本文档的范围。
Because the protocol is new and not widely deployed, it is unclear how this protocol will eventually affect DNA in IPv4 or IPv6 networks.
由于该协议是新的且未广泛部署，目前尚不清楚该协议最终将如何影响IPv4或IPv6网络中的DNA。
In 802.3 networks, Network Interface Cards (NICs) are often capable of returning a speed and duplex indication to the host. Changes in these characteristics may indicate a connection to a new layer 2 network.
在802.3网络中，网络接口卡（NIC）通常能够向主机返回速度和双工指示。这些特性的变化可能表明连接到新的第2层网络。
Link-layer indications in Ethernet-like networks are complicated by additional unadvertised delays due to spanning tree calculations. This may cause re-indication or retraction of indications previously sent to upper layer protocols.
类似以太网的网络中的链路层指示由于生成树计算而产生的额外未广告延迟而变得复杂。这可能导致重新指示或收回先前发送给上层协议的指示。
Attackers may spoof various indications at the link layer, or manipulate the physical medium directly in an effort to confuse the host about the state of the link layer. For instance, attackers may spoof error messages or disturb the wireless medium to cause the host to move its connection elsewhere or even to disconnect. Attackers may also spoof information to make the host believe it has a connection when, in reality, it does not. In addition, wireless networks such as 802.11 are susceptible to an attack called the "Evil Twin" attack where an attacker sets up an Access Point with the same SSID as a legitimate one and gets the use to connect to the fake access point instead of the real one. These attacks may cause use of non-preferred networks or even denial of service.
攻击者可能在链路层伪造各种指示，或直接操纵物理介质，试图使主机混淆链路层的状态。例如，攻击者可能伪造错误消息或干扰无线媒体，导致主机将其连接移动到其他位置，甚至断开连接。攻击者还可能伪造信息，使主机相信它有连接，而实际上它没有。此外，802.11等无线网络容易受到称为“邪恶孪生”攻击的攻击，即攻击者使用与合法SSID相同的SSID设置接入点，并使用该接入点连接到假接入点而不是真实接入点。这些攻击可能导致使用非首选网络，甚至拒绝服务。
This specification does not provide any protection of its own for the indications from the lower layers. But the vulnerabilities can be mitigated through the use of techniques in other parts of the protocol stack. In particular, it is recommended that authentication, replay, and integrity protection of link-layer management messages are enabled when available. For example, the IEEE 802.1ae standard [IEEE-802.1ae] defines such mechanisms for IEEE 802-compliant MAC layers. Additionally, the protocol stack may also use some network-layer mechanisms to achieve partial protection. For instance, SEND [RFC3971] could be used to confirm secure reachability with a router. However, network layer mechanisms are unable to deal with all problems, such as insecure lower-layer notifications that lead to the link not functioning properly.
本规范不为下层显示提供任何保护。但是，可以通过在协议栈的其他部分使用技术来缓解这些漏洞。特别是，建议在可用时启用链路层管理消息的身份验证、重播和完整性保护。例如，IEEE 802.1ae标准[IEEE-802.1ae]为符合IEEE 802的MAC层定义了此类机制。此外，协议栈还可以使用一些网络层机制来实现部分保护。例如，SEND[RFC3971]可用于确认路由器的安全可达性。但是，网络层机制无法处理所有问题，例如导致链接无法正常运行的不安全下层通知。
In addition to the people listed in the author list, text for the specific link-layer technologies covered by this document was contributed by Thomas Noel (IEEE 802.11b) and Greg Daley (IEEE 802.3). The authors would like to thank them for their efforts in bringing this document to fruition.
除了作者列表中列出的人员外，本文档所涵盖的特定链路层技术的文本由Thomas Noel（IEEE 802.11b）和Greg Daley（IEEE 802.3）提供。作者要感谢他们为使本文件取得成果所作的努力。
The authors would like to acknowledge Bernard Aboba, Sanjeev Athalye, JinHyeock Choi, John Loughney, Pekka Nikander, Brett Pentland, Tom Petch, Dan Romascanu, Pekka Savola, Steve Bellovin, Thomas Narten, Matt Mathis, Alfred Hoenes, and Muhammad Mukarram bin Tariq for their useful comments and suggestions.
作者要感谢伯纳德·阿博巴、桑吉夫·阿萨耶、崔金赫、约翰·洛尼、佩卡·尼坎德、布雷特·彭特兰、汤姆·佩奇、丹·罗马斯坎努、佩卡·萨沃拉、史蒂夫·贝洛文、托马斯·纳顿、马特·马蒂斯、阿尔弗雷德·霍恩斯和穆罕默德·穆卡拉姆·本·塔里克提出的有用的评论和建议。
[CDMA2K] "cdma2000 Wireless IP Network Standard", , December 2000.
[CDMA2K]“cdma2000无线IP网络标准”，2000年12月。
[GPRS] "Digital cellular telecommunications system (Phase 2+); General Packet Radio Service (GPRS) Service description; Stage 2", 3GPP TS 03.60 version 7.9.0 Release 98.
[GPRS]“数字蜂窝通信系统（第2+阶段）；通用分组无线业务（GPRS）服务说明；第2阶段”，3GPP TS 03.60版本7.9.0发行版98。
[GPRS-LINK] "Digital cellular telecommunications system (Phase 2+); Radio subsystem link control", 3GPP GSM 03.05 version 7.0.0 Release 98.
[GPRS-LINK]“数字蜂窝通信系统（第2+阶段）；无线电子系统链路控制”，3GPP GSM 03.05版本7.0.0发行版98。
[IEEE-802.11a] Institute of Electrical and Electronics Engineers, "IEEE Std 802.11a-1999, supplement to IEEE Std 802.11-1999, Part 11: Wireless MAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: High-speed Physical Layer in the 5 GHZ band", IEEE Standard 802.11a, September 1999.
[IEEE-802.11a]电气和电子工程师协会，“IEEE标准802.11a-1999，IEEE标准802.11a补充，IEEE标准802.11-1999，第11部分：无线城域网媒体访问控制（MAC）和物理层（PHY）规范：5GHz频段的高速物理层”，IEEE标准802.11a，1999年9月。
[IEEE-802.11b] Institute of Electrical and Electronics Engineers, "IEEE Std 802 Part 11, Information technology - Telecomunications and information exchange between systems - Local and metropolitan area networks - Specific requirements - Part 11: Wireless Lan Medium Access Control (MAC) And Physical Layer (PHY) Specifications", IEEE Standard 802.11b, August 1999.
[IEEE-802.11b]电气和电子工程师协会，“IEEE标准802第11部分，信息技术-系统间的远程通信和信息交换-局域网和城域网-特定要求-第11部分：无线Lan介质访问控制（MAC）和物理层（PHY）规范”，IEEE标准802.11b，1999年8月。
[IEEE-802.11g] Institute of Electrical and Electronics Engineers, "IEEE Std 802.11g-2003, Amendment to IEEE Std 802.11, 1999 edition, Part 11: Wireless MAN Medium Access Control (MAC) and Physical Layer (PHY) specifications. Amendment 4: Further Higher Data Rate Extension in the 2.4 GHz Band", IEEE Standard 802.11g, June 2003.
[IEEE-802.11g]电气和电子工程师协会，“IEEE标准802.11g-2003，对IEEE标准802.11的修订，1999年版，第11部分：无线城域网媒体访问控制（MAC）和物理层（PHY）规范。修订件4：在2.4 GHz频段进一步提高数据速率扩展”，IEEE标准802.11g，2003年6月。
[IEEE-802.11i] Institute of Electrical and Electronics Engineers, "Supplement to STANDARD FOR Telecommunications and Information Exchange between Systems - LAN/MAN Specific Requirements - Part 11: Wireless Medium Access Control (MAC) and physical layer (PHY) specifications: Specification for Enhanced Security", IEEE 802.11i, December 2004.
[IEEE-802.11i]电气和电子工程师协会，“系统间电信和信息交换标准的补充-局域网/城域网特定要求-第11部分：无线媒体访问控制（MAC）和物理层（PHY）规范：增强安全规范”，IEEE 802.11i，2004年12月。
[IEEE-802.1D] Institute of Electrical and Electronics Engineers, "IEEE standard for local and metropolitan area networks - common specifications - Media access control (MAC) Bridges", ISO/IEC IEEE Std 802.1D, 2004.
[IEEE-802.1D]电气和电子工程师协会，“局域网和城域网IEEE标准-通用规范-媒体访问控制（MAC）网桥”，ISO/IEC IEEE标准802.1D，2004年。
[IEEE-802.1ab] Institute of Electrical and Electronics Engineers, "Draft Standard for Local and Metropolitan Networks: Station and Media Access Control Connectivity Discovery (Draft 13)", IEEE draft Std 802.1AB, 2004.
[IEEE-802.1ab]电气和电子工程师协会，“本地和城域网标准草案：站点和媒体访问控制连接发现（草案13）”，IEEE标准草案802.1ab，2004年。
[IEEE-802.1ae] Institute of Electrical and Electronics Engineers, "IEEE Std 802.1AE, Local and Metropolitan Area Networks - Media Access Control (MAC) Security", IEEE Standard 802.1ae, June 2006.
[IEEE-802.1ae]电气和电子工程师协会，“IEEE标准802.1ae，局域网和城域网-媒体访问控制（MAC）安全”，IEEE标准802.1ae，2006年6月。
[IEEE-802.3] Institute of Electrical and Electronics Engineers, "IEEE standard for local and metropolitan area networks - Specific Requirements, Part 3: Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications", ISO/IEC IEEE Std 802.3, 2002.
[IEEE-802.3]电气和电子工程师协会，“局域网和城域网IEEE标准-具体要求，第3部分：带冲突检测的载波侦听多址接入（CSMA/CD）接入方法和物理层规范”，ISO/IEC IEEE Std 802.3，2002年。
[RFC1332] McGregor, G., "The PPP Internet Protocol Control Protocol (IPCP)", RFC 1332, May 1992.
[RFC1332]McGregor，G.“PPP互联网协议控制协议（IPCP）”，RFC1332，1992年5月。
[RFC1661] Simpson, W., "The Point-to-Point Protocol (PPP)", STD 51, RFC 1661, July 1994.
[RFC1661]辛普森，W.“点对点协议（PPP）”，标准51，RFC1661，1994年7月。
[RFC2462] Thomson, S. and T. Narten, "IPv6 Stateless Address Autoconfiguration", RFC 2462, December 1998.
[RFC2462]Thomson，S.和T.Narten，“IPv6无状态地址自动配置”，RFC2462，1998年12月。
[RFC2472] Haskin, D. and E. Allen, "IP Version 6 over PPP", RFC 2472, December 1998.
[RFC2472]Haskin，D.和E.Allen，“PPP上的IP版本6”，RFC 24721998年12月。
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3315]Droms，R.，Bound，J.，Volz，B.，Lemon，T.，Perkins，C.，和M.Carney，“IPv6的动态主机配置协议（DHCPv6）”，RFC3315，2003年7月。
[RFC3971] Arkko, J., Kempf, J., Zill, B., and P. Nikander, "SEcure Neighbor Discovery (SEND)", RFC 3971, March 2005.
[RFC3971]Arkko，J.，Kempf，J.，Zill，B.，和P.Nikander，“安全邻居发现（SEND）”，RFC 39712005年3月。
[RFC4135] Choi, JH. and G. Daley, "Goals of Detecting Network Attachment in IPv6", RFC 4135, August 2005.
[RFC4135]崔，JH。和G.Daley，“在IPv6中检测网络连接的目标”，RFC 41352005年8月。
[GPRS-CN] "Technical Specification Group Core Network; Internetworking between the Public Land Mobile Network (PLMN) supporting packet based services and Packet Data Networks (PDN) (Release 6)", 3GPP TS 29.061 version 6.1.0 2004-06.
[GPRS-CN]“技术规范组核心网络；支持分组业务的公共陆地移动网络（PLMN）与分组数据网络（PDN）之间的互联（第6版）”，3GPP TS 29.061版本6.1.0 2004-06。
[GPRS-GSSA] "Technical Specification Group Services and System Aspect; General Packet Radio Service (GPRS) Service description; Stage 2 (Release 6)", 3GPP TS 23.060 version 6.5.0 2004-06.
[GPRS-GSSA]“技术规范组服务和系统方面；通用分组无线业务（GPRS）服务说明；第2阶段（第6版）”，3GPP TS 23.060版本6.5.0 2004-06。
[RFC2461] Narten, T., Nordmark, E., and W. Simpson, "Neighbor Discovery for IP Version 6 (IPv6)", RFC 2461, December 1998.
[RFC2461]Narten，T.，Nordmark，E.，和W.Simpson，“IP版本6（IPv6）的邻居发现”，RFC2461，1998年12月。
[RFC4068] Koodli, R., "Fast Handovers for Mobile IPv6", RFC 4068, July 2005.
[RFC4068]Koodli，R.，“移动IPv6的快速切换”，RFC4068，2005年7月。
[RFC4881] El Malki, K., "Low-Latency Handoffs in Mobile IPv4", RFC 4881, June 2007.
[RFC4881]El Malki，K.，“移动IPv4中的低延迟切换”，RFC 48812007年6月。
Authors' Addresses
作者地址
Suresh Krishnan (editor) Ericsson Research 8400 Decarie Blvd. Town of Mount Royal, QC Canada
Suresh Krishnan（编辑）爱立信研究院，德克里大道8400号。加拿大皇家山镇
EMail: suresh.krishnan@ericsson.com
EMail: suresh.krishnan@ericsson.com
Nicolas Montavont GET ENST Bretagne 2, rue de la chataigneraie Cesson-Sevigne 35576 France
Nicolas Montavont GET ENST Bretagne 2，法国塞森塞维涅城堡街35576号
Phone: (33) 2 99 12 70 23 EMail: nicolas.montavont@enst-bretagne.fr
电话：（33）299127023电子邮件：尼古拉斯。montavont@enst-布雷塔涅
Eric Njedjou France Telecom 4, Rue du Clos Courtel BP 91226 Cesson Sevigne 35512 France
Eric Njedjou法国电信4号，英国石油公司，邮编：91226塞森塞维涅，邮编：35512
Phone: +33 299124878
EMail: eric.njedjou@orange-ftgroup.com
Phone: +33 299124878
EMail: eric.njedjou@orange-ftgroup.com
Siva Veerepalli Qualcomm 5775 Morehouse Drive San Diego, CA 92131 USA
Siva Veerepalli高通公司5775 Morehouse Drive San Diego，CA 92131美国
Phone: +1 858 658 4628
EMail: sivav@qualcomm.com
Phone: +1 858 658 4628
EMail: sivav@qualcomm.com
Alper E. Yegin (editor) Samsung Istanbul Turkey
阿尔珀·E·耶金（编辑）土耳其伊斯坦布尔三星
Phone: +90 533 348 2402
EMail: a.yegin@partner.samsung.com
Phone: +90 533 348 2402
EMail: a.yegin@partner.samsung.com
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