Network Working Group H. Yokota
Request for Comments: 5271 KDDI Lab
Category: Informational G. Dommety
Cisco Systems, Inc.
June 2008
Network Working Group H. Yokota
Request for Comments: 5271 KDDI Lab
Category: Informational G. Dommety
Cisco Systems, Inc.
June 2008
Mobile IPv6 Fast Handovers for 3G CDMA Networks
3G-CDMA网络中的移动IPv6快速切换
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
Mobile IPv6 is designed to maintain its connectivity while moving from one network to another. It is adopted in 3G CDMA networks as a way to maintain connectivity when the mobile node (MN) moves between access routers. However, this handover procedure requires not only movement detection by the MN, but also the acquisition of a new Care-of Address and Mobile IPv6 registration with the new care-of address before the traffic can be sent or received in the target network. During this period, packets destined for the mobile node may be lost, which may not be acceptable for a real-time application such as Voice over IP (VoIP) or video telephony. This document specifies fast handover methods in the 3G CDMA networks in order to reduce latency and packet loss during handover.
移动IPv6旨在在从一个网络移动到另一个网络的同时保持其连接性。在3G-CDMA网络中，当移动节点（MN）在接入路由器之间移动时，它被用作保持连接的一种方式。然而，该切换过程不仅需要MN进行移动检测，而且还需要在目标网络中发送或接收流量之前获取新的转交地址并使用新的转交地址进行移动IPv6注册。在此期间，目的地为移动节点的分组可能丢失，这对于诸如IP语音（VoIP）或视频电话之类的实时应用来说可能是不可接受的。本文件规定了3G CDMA网络中的快速切换方法，以减少切换过程中的延迟和数据包丢失。
Table of Contents
目录
1. Introduction ....................................................2
2. Requirements Notation ...........................................3
3. Terminology .....................................................3
4. Network Reference Model for Mobile IPv6 over 3G CDMA Networks ...4
5. Fast Handover Procedures ........................................6
5.1. Predictive Fast Handover ...................................7
5.2. Reactive Fast Handover ....................................12
5.3. Considerations on the Link Indications ....................15
6. Message Format .................................................15
6.1. Handover Assist Information Option ........................15
6.2. Mobile Node Identifier Option .............................16
6.3. New Flag Extension to FBU Message .........................17
6.4. New Flag Extension to PrRtAdv Message .....................17
7. Security Considerations ........................................18
8. IANA Considerations ............................................18
9. Acknowledgements ...............................................19
10. References ....................................................19
10.1. Normative References .....................................19
10.2. Informative References ...................................19
1. Introduction ....................................................2
2. Requirements Notation ...........................................3
3. Terminology .....................................................3
4. Network Reference Model for Mobile IPv6 over 3G CDMA Networks ...4
5. Fast Handover Procedures ........................................6
5.1. Predictive Fast Handover ...................................7
5.2. Reactive Fast Handover ....................................12
5.3. Considerations on the Link Indications ....................15
6. Message Format .................................................15
6.1. Handover Assist Information Option ........................15
6.2. Mobile Node Identifier Option .............................16
6.3. New Flag Extension to FBU Message .........................17
6.4. New Flag Extension to PrRtAdv Message .....................17
7. Security Considerations ........................................18
8. IANA Considerations ............................................18
9. Acknowledgements ...............................................19
10. References ....................................................19
10.1. Normative References .....................................19
10.2. Informative References ...................................19
Mobile IPv6 [2] allows mobile nodes (MNs) to maintain persistent IP connectivity while the MN moves around in the IPv6 network. It is adopted in 3G CDMA networks for handling host-based mobility management [12]. During handover, however, the mobile node (MN) needs to switch the radio link to obtain a new Care-of Address (CoA) and to re-register with the home agent (HA), which may cause a communication disruption. This is not desirable for real-time applications such as VoIP and video telephony. To reduce this disruption time or latency, a fast handover protocol for Mobile IPv6 [3] is proposed. RFC 4260 [7] further describes how this Mobile IPv6 Fast Handover could be implemented on link layers conforming to the IEEE 802.11 suite of specifications. However, 3G CDMA and IEEE 802.11 networks are substantially different in the radio access, the representations of the network nodes or parameters, and the network attachment procedures; for example, the beacon scanning or New Access Router (NAR) discovery based on [Access Point Identifier, Access Router-info (AP-ID, AR-info)] tuples specified in RFC 4260 can not be directly applied to 3G CDMA networks. This document therefore specifies how Mobile IPv6 fast handovers can be applied in the 3G CDMA networks.
移动IPv6[2]允许移动节点（MN）在IPv6网络中移动时保持持久的IP连接。它在3G CDMA网络中用于处理基于主机的移动性管理[12]。然而，在切换期间，移动节点（MN）需要切换无线链路以获得新的转交地址（CoA）并向归属代理（HA）重新注册，这可能导致通信中断。这对于实时应用程序（如VoIP和视频电话）是不可取的。为了减少这种中断时间或延迟，提出了一种适用于移动IPv6的快速切换协议[3]。RFC 4260[7]进一步描述了如何在符合IEEE 802.11规范套件的链路层上实现这种移动IPv6快速切换。然而，3G-CDMA和ieee802.11网络在无线电接入、网络节点或参数的表示以及网络连接过程方面有实质性的不同；例如，基于RFC 4260中指定的[接入点标识符，接入路由器信息（AP-ID，AR-info）]元组的信标扫描或新接入路由器（NAR）发现不能直接应用于3G CDMA网络。因此，本文件规定了如何在3G CDMA网络中应用移动IPv6快速切换。
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 [1].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照[1]中所述进行解释。
This document refers to [3] for Mobile IPv6 fast handover terminology. Terms that first appear in this document are defined below:
本文档参考[3]中的移动IPv6快速切换术语。本文件中首次出现的术语定义如下：
Access Network Identifier (ANID): An identifier that is used by the Packet Data Serving Node (PDSN) to determine whether the MN is being handed off from the access network that was not previously using this PDSN. Anytime the MN crosses into a new region, which is defined by the ANID, it must re-register with that access network. The ANID is further composed of the System ID (SID), Network ID (NID), and Packet Zone ID (PZID) and these values are administered by the operator. The lengths of the SID, NID, and PZID are 2 octets, 2 octets, and 1 octet, respectively. Thus, that of the ANID occupies 5 octets [11].
接入网络标识符（ANID）：分组数据服务节点（PDSN）使用的标识符，用于确定MN是否从先前未使用此PDSN的接入网络转移。当MN进入ANID定义的新区域时，它必须在该接入网络中重新注册。ANID进一步由系统ID（SID）、网络ID（NID）和分组区域ID（PZID）组成，并且这些值由操作员管理。SID、NID和PZID的长度分别为2个八位组、2个八位组和1个八位组。因此，ANID占据5个八位组[11]。
Forward Pilot Channel: A portion of the Forward Channel that carries the pilot. The Forward Channel is a portion of the physical layer channels transmitted from the 3G CDMA access network to the MN. Further, several sets of pilots (e.g., the active set or neighbor set) are defined to determine when and where to handover.
前向导频信道：承载导频的前向信道的一部分。前向信道是从3G CDMA接入网络发送到MN的物理层信道的一部分。此外，定义多组导频（例如，活动集或相邻集）以确定何时和何处进行切换。
Home Link Prefix (HLP): The prefix address assigned to the home link where the MN should send the binding update message. This is also called Home Network Prefix (HNP) and one of the bootstrap parameters for the MN.
主链接前缀（HLP）：分配给主链接的前缀地址，MN应在其中发送绑定更新消息。这也称为家庭网络前缀（HNP）和MN的引导参数之一。
International Mobile Subscriber Identity (IMSI): The IMSI is a string of decimal digits, up to a maximum of 15 digits, that identifies a unique mobile terminal or mobile subscriber internationally. The IMSI consists of three fields: the Mobile Country Code (MCC), the Mobile Network Code (MNC), and the Mobile Subscriber Identification Number (MSIN). An example of the IMSI is "440701234567890", where "440" is the MCC, "70" is the MNC, and "1234567890" is the MSIN. The IMSI conforms to the ITU-T E.212 numbering standard [6]. In this specification, IMSI is an ASCII string that consists of not more than 15 decimal digits (ASCII values between 30 and 39 hexadecimal), one character per IMSI digit. The above example would therefore be encoded as "34 34 30 37 30 31 32 33 34 35 36 37 38 39 30" in hexadecimal notation.
国际移动用户标识（IMSI）：IMSI是一组十进制数字，最多15位，用于在国际上标识唯一的移动终端或移动用户。IMSI由三个字段组成：移动国家代码（MCC）、移动网络代码（MNC）和移动用户标识号（MSIN）。IMSI的一个例子是“440701234567890”，其中“440”是MCC，“70”是MNC，“1234567890”是MSIN。IMSI符合ITU-T E.212编号标准[6]。在本规范中，IMSI是一个ASCII字符串，由不超过15个十进制数字（ASCII值在30到39个十六进制之间）组成，每个IMSI数字一个字符。因此，上述示例将以十六进制表示法编码为“34 34 30 37 30 31 32 33 34 35 36 37 38 39 30”。
Mobile Identity (MN ID): An identifier of the Mobile Node that is used by the access network. The value (e.g., IMSI) is unique within the operator's network.
移动标识（MN ID）：接入网络使用的移动节点的标识符。该值（如IMSI）在运营商网络中是唯一的。
Packet Data Serving Node (PDSN): An entity that routes MN originated or MN terminated packet data traffic. A PDSN establishes, maintains, and terminates link-layer sessions to MNs. A PDSN is the access router in the visited access provider network.
分组数据服务节点（PDSN）：路由MN发起或MN终止的分组数据流量的实体。PDSN建立、维护和终止到MNs的链路层会话。PDSN是访问的接入提供商网络中的接入路由器。
Sector Address Identifier (SectorID): A typical cell divides its coverage area into several sectors. In 3G CDMA systems, each sector uses a different PN (Pseudo Noise) code offset and is associated with SectorID. The SectorID is 128 bits long and can be represented in the IPv6 address format [8].
扇区地址标识符（SectorID）：一个典型的小区将其覆盖区域划分为几个扇区。在3G CDMA系统中，每个扇区使用不同的PN（伪噪声）码偏移量，并与扇区ID相关联。扇区ID的长度为128位，可以用IPv6地址格式表示[8]。
Figure 1 shows a simplified reference model of the Mobile IP enabled 3G CDMA networks. The home agent (HA) and Authentication, Authorization, and Accounting (AAA) server of the mobile node (MN) reside in the home IP network, and the MN roams within or between the access provider network(s). Usually, the home IP network is not populated by the MNs, which are instead connected only to the access provider networks. Prior to the Mobile IPv6 registration, the MN establishes a 3G CDMA access technology specific link-layer connection with the access router (AR). When the MN moves from one AR to another, the link-layer connection is re-established, and a Mobile IPv6 handover is performed. Those ARs reside in either the same or different access provider network(s). The figure shows the situation, where the MN moves from the Previous Access Router (PAR) to the New Access Router (NAR) via the radio access network (RAN).
图1显示了支持移动IP的3G CDMA网络的简化参考模型。移动节点（MN）的归属代理（HA）和认证、授权和计费（AAA）服务器驻留在归属IP网络中，并且MN在接入提供商网络内或之间漫游。通常，家庭IP网络不由MN填充，而是只连接到接入提供商网络。在移动IPv6注册之前，MN与接入路由器（AR）建立3G-CDMA接入技术特定的链路层连接。当MN从一个AR移动到另一个AR时，重新建立链路层连接，并执行移动IPv6切换。这些AR位于相同或不同的接入提供商网络中。该图显示了MN通过无线接入网络（RAN）从先前的接入路由器（PAR）移动到新的接入路由器（NAR）的情况。
Home IP Network
+........................+
. +--------+ +--------+ .
. | HA |--| AAA | .
. +--------+ +--------+ .
+../......\..............+
/ \
Access Provider Network(s)
+.............+ +.............+
. +---------+ . . +---------+ .
. | PAR | . . | NAR | .
. +---------+ . . +---------+ .
. |: . . :| .
. |:L2link L2link:| .
. |: . . :| .
. +----+:---+ . . +---:+----+ .
. | RAN | . . | RAN | .
. +----+:---+ . . +---:+----+ .
. |: . . :| .
. +----+ . . +----+ .
. | MN | ---------> | MN | .
. +----+ . . +----+ .
+.............+ +.............+
Home IP Network
+........................+
. +--------+ +--------+ .
. | HA |--| AAA | .
. +--------+ +--------+ .
+../......\..............+
/ \
Access Provider Network(s)
+.............+ +.............+
. +---------+ . . +---------+ .
. | PAR | . . | NAR | .
. +---------+ . . +---------+ .
. |: . . :| .
. |:L2link L2link:| .
. |: . . :| .
. +----+:---+ . . +---:+----+ .
. | RAN | . . | RAN | .
. +----+:---+ . . +---:+----+ .
. |: . . :| .
. +----+ . . +----+ .
. | MN | ---------> | MN | .
. +----+ . . +----+ .
+.............+ +.............+
Figure 1: Reference Model for Mobile IP
图1：移动IP的参考模型
In 3G CDMA networks, pilot channels transmitted by base stations allow the MN to obtain a rapid and accurate C/I (carrier to interference) estimate. This estimate is based on measuring the strength of the Forward Pilot Channel or the pilot, which is associated with a sector of a base station (BS). The MN searches for the pilots and maintains those with sufficient signal strength in the pilot sets. The MN sends measurement results, which include the offsets of the PN code in use and the C/Is in the pilot sets, to provide the radio access network (RAN) with the estimate of sectors in its neighborhood. There are several triggers for the MN to send those estimates, e.g., when the strength of a pilot in the pilot sets exceeds that of the current pilot, the MN sends the estimates to the access network. As long as the sector to which the MN is going to move belongs to the same access network, the mobility within that access network is handled by the access-specific interfaces [10] and the link-layer connection between the MN and AR can be maintained without a re-establishment. The MN can continually search for pilots without disrupting the data communication and a timely handover is assisted by the network. If, however, the serving access network finds that the sector associated with the highest pilot strength belongs to a different AR, it attempts to close the connection with the MN. The MN then attempts to get a new traffic channel assigned
在3G-CDMA网络中，由基站发送的导频信道允许MN获得快速且准确的C/I（载波干扰）估计。该估计基于测量与基站（BS）的扇区相关联的前向导频信道或导频的强度。MN搜索导频并在导频集中保持具有足够信号强度的导频。MN发送测量结果，其中包括使用中的PN码和导频集中的C/Is的偏移，以向无线接入网络（RAN）提供其附近扇区的估计。MN有几个触发器来发送这些估计，例如，当导频集中的导频强度超过当前导频的强度时，MN将估计发送到接入网络。只要MN将要移动到的扇区属于同一接入网络，该接入网络内的移动性由接入专用接口处理[10]，并且MN和AR之间的链路层连接可以在不重新建立的情况下保持。MN可以在不中断数据通信的情况下持续搜索导频，并通过网络协助及时切换。然而，如果服务接入网络发现与最高导频强度相关联的扇区属于不同的AR，则其尝试关闭与MN的连接。然后，MN尝试分配新的业务信道
in the new access network, which is followed by establishing a new connection with the new AR. This could cause a noticeable communication disruption and lead to a serious degradation of the user experience. In order to minimize the service degradation, during the handover between ARs, an IP-level fast handover approach as defined in RFC 5268 needs to be involved. If the air interface information can be used as a trigger for the handover between access routers, fast and smooth handover of Mobile IPv6 can be realized in 3G CDMA networks. The MN can continually search for pilots without disrupting the data communication and a timely handover is assisted by the network.
在新接入网络中，随后与新AR建立新连接。这可能会导致明显的通信中断，并导致用户体验严重退化。为了最小化服务降级，在ARs之间的切换期间，需要涉及RFC 5268中定义的IP级快速切换方法。如果能够将空中接口信息作为接入路由器之间切换的触发器，则可以在3G-CDMA网络中实现移动IPv6的快速平滑切换。MN可以在不中断数据通信的情况下持续搜索导频，并通过网络协助及时切换。
To assist the handover of the MN to the new AR, various types of information can be considered: the pilot sets, which include the candidates of the target sectors or BSs, the cell information where the MN resides, the serving nodes in the radio access network, and the location of the MN, if available. To identify the access network that the MN moves to or from, the Access Network Identifiers (ANID) or the subnet information can be used [9][10]. In this document, a collection of such information is called "handover assist information". In 3G CDMA networks, the Link-Layer Address of the New Access Point (AP) defined in [3] may not be available. If this is the case, the Handover Assist Information option defined in this document SHOULD be used instead.
为了帮助将MN切换到新AR，可以考虑各种类型的信息：导频集，其包括目标扇区或bs的候选、MN驻留的小区信息、无线接入网络中的服务节点以及MN的位置（如果可用）。为了识别MN移动到或从中移动的接入网络，可以使用接入网络标识符（ANID）或子网信息[9][10]。在本文件中，此类信息的集合称为“移交协助信息”。在3G CDMA网络中，[3]中定义的新接入点（AP）的链路层地址可能不可用。如果是这种情况，则应使用本文件中定义的移交辅助信息选项。
There are two modes defined in [3] according to the time of sending the FBU (Fast Binding Update); one is called "predictive mode", where the MN sends the FBU and receives the FBAck (Fast Binding Acknowledgment) on the PAR's (Previous Access Router's) link and the other is called "reactive mode", where the MN sends the FBU from the NAR's (New Access Router's) link. In the predictive mode, the time and place the MN hands off must be indicated sufficiently before the time it actually happens. In cellular systems, since handovers are controlled by the network, the predictive mode is well applied. However, if the network is not configured to be able to identify the new AR, to which the MN is moving next, in a timely manner, the reactive mode is better applied.
根据发送FBU的时间，[3]中定义了两种模式（快速绑定更新）；一种称为“预测模式”，其中MN发送FBU并在PAR（先前接入路由器）链路上接收FBAck（快速绑定确认），另一种称为“反应模式”，其中MN从NAR（新接入路由器）链路发送FBU。在预测模式下，必须在实际发生之前充分指示MN停止的时间和地点。在蜂窝系统中，由于切换由网络控制，因此预测模式得到了很好的应用。然而，如果网络未被配置为能够及时地识别MN下一个移动到的新AR，则更好地应用反应模式。
Section 2 of RFC 4907 [20] suggests architectural principles on the link indication and the effectiveness of the optimization. The link indication of this document relies on 3G CDMA networks and the effectiveness of the optimization is attributed to RFC 5268. The above principles are thus considered by the related specifications referenced in this document.
RFC 4907[20]第2节建议了链路指示的架构原则和优化的有效性。本文件的链路指示依赖于3G CDMA网络，优化的有效性归功于RFC 5268。因此，本文件中引用的相关规范考虑了上述原则。
Figure 2 shows the predictive mode of MIPv6 fast handover operation. When the MN finds a sector or a BS whose pilot signal is sufficiently strong, it initiates handover according to the following sequence:
图2显示了MIPv6快速切换操作的预测模式。当MN发现导频信号足够强的扇区或BS时，它根据以下顺序发起切换：
(a) A router solicitation for proxy router advertisement is sent to the PAR. Handover assist information for the target 3G CDMA network is attached to this message.
(a) 代理路由器广告的路由器请求被发送到PAR。目标3G CDMA网络的切换辅助信息附加到此消息。
(b) Based on the received handover assist information, the NAR is determined and a proxy router advertisement (PrRtAdv) containing the prefix of the NAR is sent back to the MN. The MN also checks that the R flag is not set in the PrRtAdv message, which indicates the network supports the predictive fast handover mode (defined later).
(b) 基于接收到的切换辅助信息，确定NAR，并将包含NAR前缀的代理路由器通告（PrRtAdv）发送回MN。MN还检查PrRtAdv消息中是否未设置R标志，这表明网络支持预测快速切换模式（稍后定义）。
(c) The MN creates an NCoA (new CoA) and sends the Fast Binding Update (FBU) with the NCoA to the PAR, which in turn sends the Handover Initiate (HI) to the NAR.
(c) MN创建NCOA（新CoA），并将NCOA的快速绑定更新（FBU）发送到PAR，继而将切换发起（HI）发送到NAR。
(d) The NAR sends the Handover Acknowledge (HAck) back to the PAR, which in turn sends the FBU acknowledgment (FBAck) to the MN.
(d) NAR将切换确认（HACK）返回到PAR，而PAR又将FBU确认（FBACK）发送到MN。
(e) The PAR starts forwarding packets toward the NCoA and the NAR captures and buffers them.
(e) PAR开始向NCOA转发分组，NAR捕获并缓冲它们。
(f) The link-layer connection associated with the PAR is closed and a new traffic channel is assigned in the new access network.
(f) 与PAR相关联的链路层连接被关闭，并且在新的接入网络中分配新的业务信道。
(g) The MN attaches to the new access network. The attachment procedure is access technology specific and that for 3G CDMA network including the PPP transactions is described later.
(g) MN连接到新的接入网络。连接过程是特定于接入技术的，包括PPP事务的3G CDMA网络的连接过程将在后面描述。
(h) The MN sends the Unsolicited Neighbor Advertisement (UNA).
(h) MN发送未经请求的邻居通告（UNA）。
(i) The NAR starts delivering packets to the MN.
(i) NAR开始向MN发送数据包。
(j) The MN sends the Binding Update (BU) to the HA to update the Binding Cache Entry (BCE) with the NCoA, and the HA sends back the Binding Acknowledgment (BA) to the MN.
(j) MN将绑定更新（BU）发送给HA，以使用NCoA更新绑定缓存项（BCE），HA将绑定确认（BA）发送回MN。
MN PAR NAR HA AAA
| RtSolPr | | | |
(a) |------------->| | | |
| PrRtAdv | | | |
(b) |<-------------| | | |
| FBU | Hl | | |
(c) |------------->|-------------->| | |
| FBack | HAck | | |
(d) |<-------------|<--------------| | |
| |forward packets| | |
(e) | |==============>|(buffering) | |
| | | | |
(f) handover | | | |
| | | | |
+--------------------------------------------------------------+
(g) | Attachment procedure |
+--------------------------------------------------------------+
| UNA | | |
(h) |----------------------------->| | |
| deliver packets | | |
(i) |<=============================| | |
| | BU/BA | | |
(j) |<------------------------------------------->| |
| | | | |
MN PAR NAR HA AAA
| RtSolPr | | | |
(a) |------------->| | | |
| PrRtAdv | | | |
(b) |<-------------| | | |
| FBU | Hl | | |
(c) |------------->|-------------->| | |
| FBack | HAck | | |
(d) |<-------------|<--------------| | |
| |forward packets| | |
(e) | |==============>|(buffering) | |
| | | | |
(f) handover | | | |
| | | | |
+--------------------------------------------------------------+
(g) | Attachment procedure |
+--------------------------------------------------------------+
| UNA | | |
(h) |----------------------------->| | |
| deliver packets | | |
(i) |<=============================| | |
| | BU/BA | | |
(j) |<------------------------------------------->| |
| | | | |
Figure 2: MIPv6 Fast Handover Operation (Predictive Mode)
图2:MIPv6快速切换操作（预测模式）
It is assumed that the NAR can be identified by the PAR leveraging the handover assist information from the MN. To perform the predictive mode, the MN MUST send the FBU before the connection with the current access network is closed. If the MN fails to send the FBU before handover, it SHOULD fall back to the reactive mode. Even if the MN successfully sends the FBU, its reception by the PAR may be delayed for various reasons such as congestion. If the NAR receives the HI triggered by the delayed FBU after the reception of the UNA ((c) comes after (h)), then the NAR SHOULD send the HAck with handover not accepted and behave as the reactive mode.
假定NAR可以通过PAR利用来自MN的切换辅助信息来识别。为了执行预测模式，MN必须在与当前接入网络的连接关闭之前发送FBU。如果MN在切换前未能发送FBU，则应返回到反应模式。即使MN成功发送FBU，其PAR的接收也可能由于各种原因如拥塞而延迟。如果NAR在收到UNA后收到延迟FBU触发的HI（（c）在（h）之后），则NAR应发送未接受切换的HAck，并作为反应模式。
In (a), Router Solicitation for Proxy Advertisement (RtSolPr) is supposed to include the New Access Point and the MN Link-Layer Address (LLA) options (Option Code=1 and 2, respectively) according to [3]. The New AP-LLA option MAY be replaced by the handover assist information option in 3G CDMA networks. As for the MN-LLA option, if the LLA for the MN is not available, 3G specific IDs such as IMSI[11] MAY be used. If this is the case, the MN ID option defined in Section 6.2, which can support other types of IDs and a length that is not necessarily multiples of 8 octets, SHOULD be used instead of the MN-LLA option.
在（a）中，根据[3]，代理广告的路由器请求（RtSolPr）应包括新接入点和MN链路层地址（LLA）选项（选项代码分别为1和2）。在3G CDMA网络中，新的AP-LLA选项可能会被切换辅助信息选项所取代。对于MN-LLA选项，如果MN的LLA不可用，则可以使用诸如IMSI[11]之类的3G特定ID。在这种情况下，应使用第6.2节中定义的MN ID选项，该选项可支持其他类型的ID，且长度不一定是8个八位字节的倍数，而不是MN-LLA选项。
In (b), PrRtAdv MUST include options for the IP address of the NAR, which may be the link-local address, and the prefix for the MN. The PAR SHOULD be able to identify the NAR from the handover assist information provided by the MN.
在（b）中，PrRtAdv必须包括NAR的IP地址选项（可能是链路本地地址）和MN的前缀。PAR应该能够从MN提供的切换辅助信息中识别NAR。
Figure 3 shows the call flow for the initial attachment in the 3G CDMA network [12]. After the traffic channel is assigned, the MN first establishes a link-layer connection between itself and the access router. As a link-layer protocol, PPP is considered in this figure, and a PPP handshake is depicted as an example. After a link-layer connection is established, the MN registers with the HA by sending a Binding Update message. There are several parameters for using Mobile IPv6 such as the home address (HoA), the Care-of Address (CoA), the home agent address (HA), and the home link prefix (HLP). In [12], obtaining these values is called bootstrapping, and the bootstrapping information can be obtained during the link-layer establishment phase and/or the mobility binding phase [13].
图3显示了3G CDMA网络中初始连接的呼叫流[12]。在分配业务信道之后，MN首先在其自身和接入路由器之间建立链路层连接。作为链路层协议，本图中考虑了PPP，并以PPP握手为例进行了描述。建立链路层连接后，MN通过发送绑定更新消息向HA注册。使用移动IPv6有几个参数，如家庭地址（HoA）、转交地址（CoA）、家庭代理地址（HA）和家庭链路前缀（HLP）。在[12]中，获得这些值称为自举，并且自举信息可以在链路层建立阶段和/或移动性绑定阶段获得[13]。
MN PAR NAR HA AAA
/ | (serving PDSN) (target PDSN) | |
| | LCP | | | |
| (1) |<----------------------->| | |
| | CHAP/PAP | Access-Request/Accept |
| (2) |<----------------------->|<-------------|------->|
| | | +------+ | | |
| (3) | | | HA |<---------+ |
| | | +------+ | |
|+........................................+ | |
|. | | . | |
|. | IPv6CP(IF-ID) | . | |
|.(4)* |<---------|------------->| . | |
(g)< . +---------+ | | | . | |
|.(5)*| LL-addr |<-+ | | . | |
|. +---------+ | | . | |
|. | | . | |
|. | RA(prefix) | . | |
|.(6)* |<---------|--------------| . | |
|. +-----+ | | | . | |
|.(7)*| CoA |<-----+ | | . | |
|. +-----+ | | . | |
|+........................................+ | |
| | DHCPv6(HA) | | |
| (8) |<---------------+------->| | |
| +-----+ | | | | |
| (9) | HA |<-----------+ | | |
| +-----+ | | | |
| | | | | |
\ | | | | |
MN PAR NAR HA AAA
/ | (serving PDSN) (target PDSN) | |
| | LCP | | | |
| (1) |<----------------------->| | |
| | CHAP/PAP | Access-Request/Accept |
| (2) |<----------------------->|<-------------|------->|
| | | +------+ | | |
| (3) | | | HA |<---------+ |
| | | +------+ | |
|+........................................+ | |
|. | | . | |
|. | IPv6CP(IF-ID) | . | |
|.(4)* |<---------|------------->| . | |
(g)< . +---------+ | | | . | |
|.(5)*| LL-addr |<-+ | | . | |
|. +---------+ | | . | |
|. | | . | |
|. | RA(prefix) | . | |
|.(6)* |<---------|--------------| . | |
|. +-----+ | | | . | |
|.(7)*| CoA |<-----+ | | . | |
|. +-----+ | | . | |
|+........................................+ | |
| | DHCPv6(HA) | | |
| (8) |<---------------+------->| | |
| +-----+ | | | | |
| (9) | HA |<-----------+ | | |
| +-----+ | | | |
| | | | | |
\ | | | | |
Figure 3: Attachment Procedure in 3G CDMA Network
图3:3G CDMA网络中的连接过程
The procedure for the initial attachment is as follows:
初始连接的程序如下所示：
(g) The link-layer connection establishment and the bootstrapping phase.
(g) 链路层连接建立和引导阶段。
(g-1) The LCP (Link Control Protocol) configure-request/response messages are exchanged.
（g-1）交换LCP（链路控制协议）配置请求/响应消息。
(g-2) User authentication (e.g., Challenge Handshake Authentication Protocol (CHAP) or Password Authentication Protocol (PAP)) is conducted.
（g-2）进行用户认证（例如，质询握手认证协议（CHAP）或密码认证协议（PAP））。
(g-3) The static bootstrapping information is conveyed from the AAA and stored in the NAR (target PDSN). The HoA and HLP can be dynamically assigned by the HA in the mobility binding phase. This step can be skipped in the handover case.
（g-3）静态自举信息从AAA传输并存储在NAR（目标PDSN）中。HA可以在移动性绑定阶段动态分配HoA和HLP。在切换情况下，可以跳过此步骤。
(g-4) Unique interface IDs are negotiated in IPv6 Control Protocol (IPv6CP).
（g-4）在IPv6控制协议（IPv6CP）中协商唯一接口ID。
(g-5) The MN configures its link-local address based on the obtained interface ID.
（g-5）MN基于获得的接口ID配置其链路本地地址。
(g-6) A router advertisement containing the prefix is received by the MN.
（g-6）MN接收包含前缀的路由器广告。
(g-7) The MN configures its CoA based on the obtained prefix.
（g-7）MN基于获得的前缀配置其CoA。
(g-8) DHCPv6 is used to obtain the static bootstrap information (e.g., the HA address). This step is performed in the initial attachment and can be skipped once the MN obtains those parameters.
（g-8）DHCPv6用于获取静态引导信息（例如HA地址）。该步骤在初始附件中执行，一旦MN获得这些参数，就可以跳过该步骤。
(g-9) The MN installs the bootstrap information for further procedures (e.g., the mobility binding).
（g-9）MN安装引导信息以用于进一步的过程（例如，移动绑定）。
As is shown in Figure 3, it takes a considerable amount of time to establish a link-layer connection and almost all of the above sequences run every time the MN attaches to a new access network. It is therefore beneficial if packets in transit to the MN are saved not only during the time period when the MN switches to the new radio channel but also during the time period when the MN establishes the link-layer connection.
如图3所示，建立链路层连接需要相当长的时间，并且每次MN连接到新的接入网络时，几乎所有上述序列都会运行。因此，如果不仅在MN切换到新无线信道的时间段期间，而且在MN建立链路层连接的时间段期间，保存传输到MN的分组是有益的。
There are several ways to configure a unique IP address for the MN. If a globally unique prefix is assigned per link as introduced in [12], the MN can use any interface ID except that of the other peer (the AR to which the MN is attached) to create a unique IP address. If this is the case, however, the PAR cannot provide the MN with a correct prefix for the new network in the PrRtAdv since such a prefix is selected by the NAR and provided in the router advertisement. The MN therefore configures a temporary NCoA with the prefix provided by the PAR and the correct NCoA MUST be assigned by the NAR. Therefore, in 3G CDMA network, the PAR MUST send the HI with the S flag set when it receives the FBU from the MN at step (c) in Figure 2.
有几种方法可以为MN配置唯一的IP地址。如果按照[12]中的介绍为每个链路分配了一个全局唯一的前缀，则MN可以使用除其他对等方（MN连接到的AR）的接口ID之外的任何接口ID来创建唯一的IP地址。然而，如果是这种情况，PAR不能为PrRtAdv中的新网络提供MN正确的前缀，因为这样的前缀由NAR选择并在路由器广告中提供。因此，MN用PAR提供的前缀配置临时NCOA，并且必须由NAR分配正确的NCOA。因此，在3G CDMA网络中，当图2中的步骤（c）接收到来自MN的FBU时，PAR必须发送带有S标志集的HI。
The UNA is supposed to include the MN-LLA [3], but the point-to-point link-layer connection may be able to uniquely identify the MN. The most required information by the UNA is the NCoA to check if there is a corresponding buffer. Therefore, in (h), the function of the UNA can be realized in several ways:
UNA应该包括MN-LLA[3]，但是点到点链路层连接可能能够唯一地识别MN。UNA最需要的信息是NCoA，以检查是否有相应的缓冲区。因此，在（h）中，UNA的功能可以通过几种方式实现：
o Since the establishment of the link-layer connection in (g) indicates readiness of data communication on the MN side, the NAR immediately checks if there is a buffer that has packets destined for the NCoA, which was configured at steps (c) - (d), and starts delivering, if any (substitution of UNA).
o 由于（g）中链路层连接的建立指示MN侧上的数据通信的准备就绪，NAR立即检查是否存在具有在步骤（c）-（d）中配置的目的地为NCoA的分组的缓冲器，并且如果有的话开始传送（UNA的替换）。
o The MN sends the UNA as defined in [3]. Instead of the MN-LLA in the LLA option, the MN ID MAY be included in the MN ID option (standard implementation of UNA).
o MN发送[3]中定义的UNA。代替LLA选项中的MN-LLA，MN ID可以包含在MN ID选项中（UNA的标准实现）。
The primary benefit of the predictive fast handover mode is that the packets destined for the MN can be buffered at the NAR, and packet loss due to handover will be much lower than that of the normal MIPv6 operation. Regarding the bootstrapping, the following benefit can be obtained, too:
预测性快速切换模式的主要优点是，目的地为MN的分组可以在NAR处缓冲，并且由于切换而导致的分组丢失将远低于正常MIPv6操作的分组丢失。关于自举，也可以获得以下好处：
o Since the NCoA can be configured via the fast handover procedures, a router advertisement is not required.
o 由于NCoA可以通过快速切换过程进行配置，因此不需要路由器通告。
Therefore, the procedures (g-4) to (g-7) can be skipped from the standard MIPv6 operation in Figure 3.
因此，可以从图3中的标准MIPv6操作中跳过过程（g-4）到（g-7）。
When the network does not support the predictive fast handover mode, the reactive fast handover is applied. In this document, a new flag is defined in PrRtAdv to inform the MN about the capability of the network (see Section 6.4). To minimize packet loss in this situation, the PAR instead of the NAR can buffer packets for the MN until the MN regains connectivity with the NAR. The NAR obtains the information of the PAR from the MN on the NAR's link and receives packets buffered at the PAR. In this case, the PAR does not need to know the IP address of the NAR or the NCoA and just waits for the NAR to contact the PAR. However, since the PAR needs to know when to buffer packets for the MN, the PAR obtains the timing of buffering from the MN via the FBU or the lower-layer signaling, e.g., an indication of the release of the connection with the MN. Details of the procedure are as follows:
当网络不支持预测性快速切换模式时，应用反应性快速切换。在本文件中，PrRtAdv中定义了一个新标志，用于通知MN网络的能力（见第6.4节）。为了在这种情况下最小化分组丢失，PAR代替NAR可以缓冲MN的分组，直到MN恢复与NAR的连通性。NAR在NAR链路上从MN获得PAR信息，并接收PAR缓冲的分组。在这种情况下，PAR不需要知道NAR或NCOA的IP地址，而只等待NAR与PAR联系。然而，由于PAR需要知道何时为MN缓冲分组，PAR通过FBU或下层信令获得从MN缓冲的定时，例如，与MN的连接释放的指示。程序详情如下:
(a) A router solicitation for proxy router advertisement MAY be sent to the PAR.
(a) 代理路由器广告的路由器请求可以发送到PAR。
(b) The proxy router advertisement MAY be sent to the MN. If the information on the NAR is not available by the PAR, "0::0" MUST be used for the options related to the NAR (e.g., IP address of the NAR).
(b) 代理路由器通告可以发送到MN。如果NAR的信息不由PAR获得，则“0：：0”必须用于与NAR相关的选项（例如，NAR的IP地址）。
(c) The MN sends the FBU or the access network indicates the close of the connection with the MN by the lower-layer signaling. If the MN cannot formulate the NCoA, "0::0", MUST be used for the NCoA in the FBU. If the B flag is set in the FBU, the PAR SHOULD start buffering packets destined for the PCoA.
(c) MN发送FBU或接入网络，通过低层信令指示与MN的连接关闭。如果MN无法制定NCoA，则必须将“0:：0”用于FBU中的NCoA。如果在FBU中设置了B标志，则PAR应该开始去往PCOA的缓冲分组。
(d) The link-layer connection associated with the PAR is closed and a new traffic channel is assigned in the new access network.
(d) 与PAR相关联的链路层连接被关闭，并且在新的接入网络中分配新的业务信道。
(e) The MN attaches to the new access network. This part is the same as described in Section 5.1 and illustrated in Figure 3.
(e) MN连接到新的接入网络。该部分与第5.1节所述内容相同，如图3所示。
(f) The MN sends the UNA to the NAR.
(f) MN将UNA发送到NAR。
(g) The MN sends the Fast Binding Update (FBU) to the PAR via the NAR.
(g) MN通过NAR向PAR发送快速绑定更新（FBU）。
(h) The NAR forwards the FBU from the MN to the PAR.
(h) NAR将FBU从MN转发到PAR。
(i) The PAR sends the Handover Initiate (HI) to the NAR with the Code set to 1.
(i) PAR将切换启动（HI）发送到NAR，代码设置为1。
(j) The NAR sends the Handover Acknowledge (HAck) back to the PAR.
(j) NAR将切换确认（HACK）返回到PAR。
(k) The PAR sends the FBAck to the NAR.
(k) PAR将FFACK发送到NAR。
(l) If the PAR is buffering packets destined for the PCoA, it starts forwarding them as well as newly arriving ones to the NAR.
(l) 如果PAR缓冲了PCoA的数据包，它开始转发它们，以及新到达的NAR。
(m) The NAR delivers the packets to the MN.
(m) NAR将数据包传递给MN。
(n) The MN sends the BU to the HA to update the BCE with the NCoA and the HA sends back the BA to the MN.
(n) MN将BU发送给HA，以使用NCoA更新BCE，HA将BA发送回MN。
MN PAR NAR HA AAA
| RtSolPr | | | |
(a) |------------->| | | |
| PrRtAdv | | | |
(b) |<-------------| | | |
| FBU | | | |
(c) |- - - - - - ->|(buffering) | | |
| | | | |
(d) handover | | | |
| | | | |
+--------------------------------------------------------------+
(e) | Attachment procedure |
+--------------------------------------------------------------+
| UNA | | |
(f) |----------------------------->| | |
| FBU | | |
(g) |----------------------------->| | |
| | FBU | | |
(h) | |<--------------| | |
| | HI | | |
(i) | |-------------->| | |
| | HAck | | |
(j) | |<--------------| | |
| | FBack | | |
(k) | |-------------->| | |
| |forward packets| | |
(l) | |==============>| | |
| deliver packets | | |
(m) |<=============================| | |
| | BU/BA | | |
(n) |<------------------------------------------->| |
| | | | |
MN PAR NAR HA AAA
| RtSolPr | | | |
(a) |------------->| | | |
| PrRtAdv | | | |
(b) |<-------------| | | |
| FBU | | | |
(c) |- - - - - - ->|(buffering) | | |
| | | | |
(d) handover | | | |
| | | | |
+--------------------------------------------------------------+
(e) | Attachment procedure |
+--------------------------------------------------------------+
| UNA | | |
(f) |----------------------------->| | |
| FBU | | |
(g) |----------------------------->| | |
| | FBU | | |
(h) | |<--------------| | |
| | HI | | |
(i) | |-------------->| | |
| | HAck | | |
(j) | |<--------------| | |
| | FBack | | |
(k) | |-------------->| | |
| |forward packets| | |
(l) | |==============>| | |
| deliver packets | | |
(m) |<=============================| | |
| | BU/BA | | |
(n) |<------------------------------------------->| |
| | | | |
Figure 4: MIPv6 Fast Handover Operation (Reactive Mode)
图4:MIPv6快速切换操作（反应模式）
To indicate the PAR to buffer packets destined for the PCoA, in step (c), a new flag 'B' is defined in the FBU. When the PAR receives the FBU with this flag set, it SHOULD buffer packets for the MN. The PAR MAY also start buffering packets for the MN based on lower layer signal during handover. Since the packets are buffered at the PAR in this scenario, the UNA, which is received and processed by the NAR, can not be used to trigger to forward the buffered packets at the PAR. In Figure 4, the HAck from the NAR is used as the trigger for the forwarding of any buffered packets.
为了指示到达PCoA的缓冲包的PAR，在步骤（c）中，在FBU中定义了新的标志“B”。当PAR接收到带有这个标志集的FBU时，它应该为MN缓冲包。PAR还可以在切换期间基于下层信号开始为MN缓冲分组。由于在这种情况下分组在PAR中被缓冲，因此，由NAR接收和处理的UNA不能用于触发以PAR转发缓冲分组。在图4中，来自NAR的攻击被用作转发任何缓冲数据包的触发器。
The handover indication from the lower layer of 3G CDMA system is reasonably reliable by the periodical reports from the MN; however, there are several situations where the target link is not available
根据MN的定期报告，来自3G CDMA系统较低层的切换指示是合理可靠的；但是，有几种情况下目标链接不可用
after the handover (step (d)) and the MN comes back to the PAR, or the MN is not able to move to the target link for some reason after the connection was closed. If this is the case, the attachment procedure is performed on the previous link. The packets buffered at the PAR SHOULD be delivered to the MN after the connection is re-established.
在切换（步骤（d））和MN返回到PAR之后，或者MN在连接关闭后由于某种原因无法移动到目标链路。如果是这种情况，则在上一个链接上执行连接程序。在重新建立连接之后，PAR缓冲的分组应被传送到MN。
This section discusses if the link indications assumed in this document meet the principles defined in Section 2 of RFC 4907[20], which suggests 11 architectural principles on the link indication and the effectiveness of the optimization. This document relies on the 3G CDMA network regarding the link indication, which is precisely specified by 3GPP2. Therefore, principles (1) to (5), (7), (8), and (11), that is, "Model Validation", "Clear Definition", "Robustness", "Recovery from Invalid Indications", "Congestion Control", "Interoperability", "Race Condition", and "Transport of Link Indications" are considered by those specs. Principle (6) "Effectiveness" mentions the effectiveness of the optimization. This document bases its effectiveness on RFC 5268. Therefore, this principle is dealt by that RFC. Principle (9) "Metric Consistency" mentions inconsistencies between link and routing layer metrics. The spec of this document does not change the routing metrics and multi-homing is not considered. Finally, principle (10) "Layer Compression", mentions an overhead reduction scheme and interoperability. This document does not deal with overhead reduction and therefore this principle does not apply.
本节讨论了本文件中假设的链路指示是否符合RFC 4907[20]第2节中定义的原则，该节提出了链路指示的11项架构原则和优化的有效性。本文档依赖于3G-CDMA网络的链路指示，这正是3GPP2所规定的。因此，这些规范考虑了原则（1）至（5）、（7）、（8）和（11），即“模型验证”、“清晰定义”、“鲁棒性”、“无效指示恢复”、“拥塞控制”、“互操作性”、“竞争条件”和“链路指示传输”。原则（6）“有效性”提到优化的有效性。本文件的有效性基于RFC 5268。因此，这一原则由该RFC处理。原则（9）“度量一致性”提到链路和路由层度量之间的不一致性。本文件的规范不会改变路由指标，也不会考虑多主路由。最后，原则（10）“层压缩”提到了开销减少方案和互操作性。本文件不涉及间接费用减少，因此本原则不适用。
If the lower layer information of the new point of attachment is not represented as the link-layer address, the following option SHOULD be used. The primary purpose of this option is to convey the handover assist information described in Section 4.
如果新附着点的下层信息未表示为链路层地址，则应使用以下选项。此选项的主要目的是传达第4节中描述的移交辅助信息。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Option-Code | HAI-Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| HAI-Value...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Option-Code | HAI-Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| HAI-Value...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
Type 29
类型29
Length The size of this option in 8 octets including the Type, Length, Option-Code, and HAI-Length (Handover Assist Information-Length) fields.
长度此选项的大小以8个八位字节表示，包括类型、长度、选项代码和HAI长度（交接辅助信息长度）字段。
Option-Code 1: Access Network Identifier (AN ID) 2: Sector ID
选项代码1：接入网络标识符（AN ID）2：扇区ID
HAI-Length The size of the HAI-Value field in octets.
HAI长度HAI值字段的大小（以八位字节为单位）。
HAI-Value The value specified by the Option-Code.
HAI值选项代码指定的值。
If those that received this message do not support this option, they SHOULD treat this option as opaque and MUST NOT drop it.
如果收到此消息的人不支持此选项，则他们应将此选项视为不透明，并且不得放弃此选项。
Option-Code indicates the particular type of handover assist information. Currently, two types of information are defined to assist the discovery of the NAR (see Section 3).
选项代码表示特定类型的移交辅助信息。目前，定义了两种类型的信息来帮助发现NAR（见第3节）。
Depending on the size of the HAI-Value field, appropriate padding MUST be used to ensure that the entire option size is a multiple of 8 octets. The HAI-Length is used to disambiguate the size of the HAI-Value.
根据HAI值字段的大小，必须使用适当的填充，以确保整个选项大小是8个八位字节的倍数。HAI长度用于消除HAI值大小的歧义。
The handover assist information MAY replace the New Access Point Link-Layer Address in 3G CDMA networks.
切换辅助信息可以替换3G-CDMA网络中的新接入点链路层地址。
This option is used to transfer the Identifier of the MN, which is not its link-layer address.
此选项用于传输MN的标识符，该标识符不是其链路层地址。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+---------------+---------------+---------------+
| Type | Length | Option-Code | MN ID-Length |
+---------------------------------------------------------------+
| MN ID ...
+-----------------------------
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+---------------+---------------+---------------+
| Type | Length | Option-Code | MN ID-Length |
+---------------------------------------------------------------+
| MN ID ...
+-----------------------------
Type 30
类型30
Length The size of this option is in 8 octets including the Type, Length, and Option-Code.
长度此选项的大小以8个八位字节为单位，包括类型、长度和选项代码。
Option-Code 1: NAI [4] 2: IMSI (See Section 3)
选项代码1:NAI[4]2:IMSI（见第3节）
MN ID-Length The length of the MN ID in octets.
MN ID Length以八位字节为单位的MN ID的长度。
MN ID MN ID value
MN ID MN ID值
The MN ID MAY replace the MN Link-Layer Address in 3G CDMA networks.
MN ID可以替换3G CDMA网络中的MN链路层地址。
The MN MUST send the FBU to the PAR with the following new (B) flag set in the previous network to indicate the PAR to buffer packets destined for the PCoA. The rest of the Binding Update message format remains the same as defined in [2] and with the additional (M), (R), and (P) flags as specified in [14], [15], and [16], respectively.
MN必须将FBU发送到与前一网络中设置的以下新的（B）标志相一致的PAR，以指示向PCOA发送的PAR到缓冲分组。绑定更新消息格式的其余部分保持与[2]中定义的相同，并分别具有[14]、[15]和[16]中指定的附加（M）、（R）和（P）标志。
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence # |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|A|H|L|K|M|R|P|B| Reserved | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Mobility options .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence # |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|A|H|L|K|M|R|P|B| Reserved | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Mobility options .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
B flag: If the 'B' flag is set, the PAR SHOULD start buffering the packets destined for the MN as specified in Section 5.2.
B标志：如果设置了“B”标志，PAR应该开始缓冲在第5.2节中指定的MN包。
A new flag 'R' is defined in the PrRtAdv to inform the MN about the fast handover mode that the network supports.
PrRtAdv中定义了一个新的标志“R”，以通知MN网络支持的快速切换模式。
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Subtype |R| Reserved | Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options ...
+-+-+-+-+-+-+-+-+-+-+-+-
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Subtype |R| Reserved | Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options ...
+-+-+-+-+-+-+-+-+-+-+-+-
R flag: If the 'R' flag is set, the network supports only the reactive handover mode. Otherwise, the network supports both the predictive and reactive fast handover mode.
R标志：如果设置了“R”标志，则网络仅支持被动切换模式。否则，网络支持预测和反应式快速切换模式。
The security considerations for Mobile IPv6 fast handover are described in [3]. When a 3G CDMA network is considered, it can be assumed that the PAR and the NAR have a trust relationship and the links between them and those between the ARs and the MN are secured. The MN is authenticated every time it attaches to the new link; therefore, the AR can securely identify the MN. Depending on the operator's policy, however, SEcure Neighbor Discovery (SEND) [18] and the shared handover key defined in [17] can also be applied.
移动IPv6快速切换的安全注意事项如[3]所述。当考虑3G CDMA网络时，可以假定PAR和NAR具有信任关系，并且它们之间的链路和ARS和MN之间的链路被保护。MN每次连接到新链路时都进行身份验证；因此，AR可以安全地识别MN。但是，根据运营商的策略，还可以应用安全邻居发现（SEND）[18]和[17]中定义的共享切换密钥。
This document defines two new IPv6 Neighbor Discovery options that have been assigned from the same space as the IPv6 Neighbor Discovery Options defined in [19].
本文档定义了两个新的IPv6邻居发现选项，它们是从与[19]中定义的IPv6邻居发现选项相同的空间分配的。
29: Handover Assist Information Option (Section 6.1)
29：移交辅助信息选项（第6.1节）
30: Mobile Node Identifier Option (Section 6.2)
30：移动节点标识符选项（第6.2节）
This document creates two new registries for the Option-Code field in the Handover Assist Information Option and that in the Mobile Node Identifier Option. The values for the Option-Code must be within the range 0-255. New values for both registries can be allocated by Standards Action or IESG approval [5].
本文档为切换辅助信息选项中的选项代码字段和移动节点标识符选项中的选项代码字段创建了两个新的注册表。选项代码的值必须在0-255范围内。可以通过标准行动或IESG批准为两个注册中心分配新值[5]。
The Option-Code values that have been assigned by IANA are as follows:
IANA分配的选项代码值如下：
Option-Code for Handover Assist Information Option
Value Description Reference
----- ---------------------------- ----------
0 Reserved
1 ANID Section 6.1
2 Sector ID Section 6.1
Option-Code for Handover Assist Information Option
Value Description Reference
----- ---------------------------- ----------
0 Reserved
1 ANID Section 6.1
2 Sector ID Section 6.1
Option-Code for Mobile Node Identifier Option
Value Description Reference
----- ---------------------------- ----------
0 Reserved
1 NAI Section 6.2
2 IMSI Section 6.2
Option-Code for Mobile Node Identifier Option
Value Description Reference
----- ---------------------------- ----------
0 Reserved
1 NAI Section 6.2
2 IMSI Section 6.2
The authors would like to thank Kuntal Chowdhury, Ashutosh Dutta, Ved Kafle, and Vijay Devarapalli for providing feedback and support for this work. The authors would also thank Sebastian Thalanany for 3GPP2 expert review.
作者要感谢Kuntal Chowdhury、Ashutosh Dutta、Ved Kafle和Vijay Devarapalli为这项工作提供反馈和支持。作者还感谢Sebastian Thalanany的3GPP2专家评审。
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[1] Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[2] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support in IPv6", RFC 3775, June 2004.
[2] Johnson，D.，Perkins，C.，和J.Arkko，“IPv6中的移动支持”，RFC 37752004年6月。
[3] Koodli, R., Ed., "Mobile IPv6 Fast Handovers", RFC 5268, June 2008.
[3] Koodli，R.，Ed.，“移动IPv6快速切换”，RFC 5268，2008年6月。
[4] Aboba, B., Beadles, M., Arkko, J., and P. Eronen, "The Network Access Identifier", RFC 4282, December 2005.
[4] Aboba，B.，Beadles，M.，Arkko，J.，和P.Eronen，“网络接入标识符”，RFC 42822005年12月。
[5] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008.
[5] Narten，T.和H.Alvestrand，“在RFCs中编写IANA注意事项部分的指南”，BCP 26，RFC 5226，2008年5月。
[6] ITU-T Recommendation, "The international identification plan for mobile terminals and mobile users", ITU-T E.212, May 2004.
[6] ITU-T建议，“移动终端和移动用户国际识别计划”，ITU-T E.212，2004年5月。
[7] McCann, P., "Mobile IPv6 Fast Handovers for 802.11 Networks", RFC 4260, November 2005.
[7] McCann，P.，“802.11网络的移动IPv6快速切换”，RFC 4260，2005年11月。
[8] 3GPP2 TSG-C, "cdma2000 High Rate Packet Data Air Interface Specification", C.S0024-A v.2.0, July 2005.
[8] 3GPP2 TSG-C，“cdma2000高速分组数据空中接口规范”，C.S0024-A v.2.0，2005年7月。
[9] 3GPP2 TSG-A, "3GPP2 Access Network Interfaces Interoperability Specification", A.S0001-A v.2.0, June 2001.
[9] 3GPP2 TSG-A，“3GPP2接入网络接口互操作性规范”，A.S0001-A v.2.0，2001年6月。
[10] 3GPP2 TSG-A, "Interoperability Specification for High Rate Packet 1 2 Data (HRPD) Access Network Interfaces - Rev A.", A.S0007-A v.2.0, May 2003.
[10] 3GPP2 TSG-A，“高速分组12数据（HRPD）接入网络接口的互操作性规范-修订版A”，A.S0007-A v.2.0，2003年5月。
[11] 3GPP2 TSG-A, "Interoperability Specification (IOS) for High Rate Packet Data (HRPD) Access Network Interfaces", 3GPP2 A.S0008-0 v3.0, May 2003.
[11] 3GPP2 TSG-A，“高速分组数据（HRPD）接入网络接口的互操作性规范（IOS）”，3GPP2 A.S0008-0 v3.0，2003年5月。
[12] 3GPP2 TSG-X, "cdma2000 Wireless IP Network Standard: Simple IP and Mobile IP services", X.S0011-002-D v.1.0, February 2006.
[12] 3GPP2 TSG-X，“cdma2000无线IP网络标准：简单IP和移动IP服务”，X.S0011-002-D v.1.0，2006年2月。
[13] Devarapalli, V., Patel, A., Keung, K., and K. Chowdhury, "Mobile IPv6 Bootstrapping for the Authentication Option Protocol", Work in Progress, September 2007.
[13] Devarapalli，V.，Patel，A.，Keung，K.，和K.Chowdhury，“认证选项协议的移动IPv6引导”，正在进行的工作，2007年9月。
[14] Soliman, H., Castelluccia, C., El Malki, K., and L. Bellier, "Hierarchical Mobile IPv6 Mobility Management (HMIPv6)", RFC 4140, August 2005.
[14] Soliman，H.，Castelluccia，C.，El Malki，K.，和L.Bellier，“分层移动IPv6移动性管理（HMIPv6）”，RFC 41402005年8月。
[15] Devarapalli, V., Wakikawa, R., Petrescu, A., and P. Thubert, "Network Mobility (NEMO) Basic Support Protocol", RFC 3963, January 2005.
[15] Devarapalli，V.，Wakikawa，R.，Petrescu，A.，和P.Thubert，“网络移动（NEMO）基本支持协议”，RFC 3963，2005年1月。
[16] Gundavell, S., Ed., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", Work in Progress, February 2008.
[16] Gundavell，S.，Ed.，Leung，K.，Devarapalli，V.，Chowdhury，K.，和B.Patil，“代理移动IPv6”，正在进行的工作，2008年2月。
[17] Kempf, J., Ed. and R. Koodli, "Distributing a Symmetric FMIPv6 Handover Key using SEND", RFC 5269, June 2008.
[17] Kempf，J.，Ed.和R.Koodli，“使用发送分发对称FMIPv6切换密钥”，RFC 5269，2008年6月。
[18] Arkko, J., Ed., Kempf, J., Zill, B., and P. Nikander, "SEcure Neighbor Discovery (SEND)", RFC 3971, March 2005.
[18] Arkko，J.，Ed.，Kempf，J.，Zill，B.，和P.Nikander，“安全邻居发现（SEND）”，RFC 39712005年3月。
[19] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, September 2007.
[19] Narten，T.，Nordmark，E.，Simpson，W.，和H.Soliman，“IP版本6（IPv6）的邻居发现”，RFC 48612007年9月。
[20] Aboba, B., Ed., "Architectural Implications of Link Indications", RFC 4907, June 2007.
[20] Aboba，B.，编辑，“连接指示的建筑含义”，RFC 49072007年6月。
Authors' Addresses
作者地址
Hidetoshi Yokota KDDI Lab 2-1-15 Ohara, Fujimino Saitama, 356-8502 JP
横田英寿KDDI实验室2-1-15-Ohara，藤野斋玉，356-8502 JP
Phone: +81 49 278 7894
Fax: +81 49 278 7510
EMail: yokota@kddilabs.jp
Phone: +81 49 278 7894
Fax: +81 49 278 7510
EMail: yokota@kddilabs.jp
Gopal Dommety Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134 US
Gopal Dommety Cisco Systems，Inc.美国加利福尼亚州圣何塞市西塔斯曼大道170号，邮编95134
Phone: +1 408 525 1404
EMail: gdommety@cisco.com
Phone: +1 408 525 1404
EMail: gdommety@cisco.com
Full Copyright Statement
完整版权声明
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