Network Working Group M. Krueger
Request for Comments: 3347 R. Haagens
Category: Informational Hewlett-Packard Corporation
C. Sapuntzakis
Stanford
M. Bakke
Cisco Systems
July 2002
Network Working Group M. Krueger
Request for Comments: 3347 R. Haagens
Category: Informational Hewlett-Packard Corporation
C. Sapuntzakis
Stanford
M. Bakke
Cisco Systems
July 2002
Small Computer Systems Interface protocol over the Internet (iSCSI) Requirements and Design Considerations
Internet上的小型计算机系统接口协议（iSCSI）要求和设计注意事项
Status of this Memo
本备忘录的状况
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 Internet Society (2002). All Rights Reserved.
版权所有（C）互联网协会（2002年）。版权所有。
Abstract
摘要
This document specifies the requirements iSCSI and its related infrastructure should satisfy and the design considerations guiding the iSCSI protocol development efforts. In the interest of timely adoption of the iSCSI protocol, the IPS group has chosen to focus the first version of the protocol to work with the existing SCSI architecture and commands, and the existing TCP/IP transport layer. Both these protocols are widely-deployed and well-understood. The thought is that using these mature protocols will entail a minimum of new invention, the most rapid possible adoption, and the greatest compatibility with Internet architecture, protocols, and equipment.
本文档规定了iSCSI及其相关基础架构应满足的要求，以及指导iSCSI协议开发工作的设计注意事项。为了及时采用iSCSI协议，IPS集团选择将协议的第一个版本集中于现有SCSI体系结构和命令以及现有TCP/IP传输层。这两个协议都得到了广泛的部署和理解。我们的想法是，使用这些成熟的协议将需要最少的新发明，最快速的采用，以及与互联网架构、协议和设备的最大兼容性。
Conventions used in this document
本文件中使用的公约
This document describes the requirements for a protocol design, but does not define a protocol standard. Nevertheless, the key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC-2119 [2].
本文件描述了协议设计的要求，但未定义协议标准。然而，本文件中的关键词“必须”、“不得”、“要求”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照RFC-2119[2]中所述进行解释。
Table of Contents
目录
1. Introduction.................................................2
2. Summary of Requirements......................................3
3. iSCSI Design Considerations..................................7
3.1. General Discussion...........................................7
3.2. Performance/Cost.............................................9
3.3. Framing.....................................................11
3.4. High bandwidth, bandwidth aggregation.......................13
4. Ease of implementation/complexity of protocol...............14
5. Reliability and Availability................................15
5.1. Detection of Data Corruption................................15
5.2. Recovery....................................................15
6. Interoperability............................................16
6.1. Internet infrastructure.....................................16
6.2. SCSI........................................................16
7. Security Considerations.....................................18
7.1. Extensible Security.........................................18
7.2. Authentication..............................................18
7.3. Data Integrity..............................................19
7.4. Data Confidentiality........................................19
8. Management..................................................19
8.1. Naming......................................................20
8.2. Discovery...................................................21
9. Internet Accessibility......................................21
9.1. Denial of Service...........................................21
9.2. NATs, Firewalls and Proxy servers...........................22
9.3. Congestion Control and Transport Selection..................22
10. Definitions.................................................22
11. References..................................................23
12. Acknowledgements............................................24
13. Author's Addresses..........................................25
14. Full Copyright Statement....................................26
1. Introduction.................................................2
2. Summary of Requirements......................................3
3. iSCSI Design Considerations..................................7
3.1. General Discussion...........................................7
3.2. Performance/Cost.............................................9
3.3. Framing.....................................................11
3.4. High bandwidth, bandwidth aggregation.......................13
4. Ease of implementation/complexity of protocol...............14
5. Reliability and Availability................................15
5.1. Detection of Data Corruption................................15
5.2. Recovery....................................................15
6. Interoperability............................................16
6.1. Internet infrastructure.....................................16
6.2. SCSI........................................................16
7. Security Considerations.....................................18
7.1. Extensible Security.........................................18
7.2. Authentication..............................................18
7.3. Data Integrity..............................................19
7.4. Data Confidentiality........................................19
8. Management..................................................19
8.1. Naming......................................................20
8.2. Discovery...................................................21
9. Internet Accessibility......................................21
9.1. Denial of Service...........................................21
9.2. NATs, Firewalls and Proxy servers...........................22
9.3. Congestion Control and Transport Selection..................22
10. Definitions.................................................22
11. References..................................................23
12. Acknowledgements............................................24
13. Author's Addresses..........................................25
14. Full Copyright Statement....................................26
The IP Storage Working group is chartered with developing comprehensive technology to transport block storage data over IP protocols. This effort includes a protocol to transport the Small Computer Systems Interface (SCSI) protocol over the Internet (iSCSI). The initial version of the iSCSI protocol will define a mapping of SCSI transport protocol over TCP/IP so that SCSI storage controllers (principally disk and tape arrays and libraries) can be attached to IP networks, notably Gigabit Ethernet (GbE) and 10 Gigabit Ethernet (10 GbE).
IP存储工作组负责开发通过IP协议传输块存储数据的综合技术。这项工作包括通过Internet（iSCSI）传输小型计算机系统接口（SCSI）协议的协议。iSCSI协议的初始版本将定义SCSI传输协议在TCP/IP上的映射，以便SCSI存储控制器（主要是磁盘、磁带阵列和库）可以连接到IP网络，特别是千兆以太网（GbE）和万兆以太网（10GbE）。
The iSCSI protocol is a mapping of SCSI to TCP, and constitutes a "SCSI transport" as defined by the ANSI T10 document SCSI SAM-2 document [SAM2, p. 3, "Transport Protocols"].
iSCSI协议是SCSI到TCP的映射，并构成ANSI T10文件SCSI SAM-2文件[SAM2，第3页，“传输协议”中定义的“SCSI传输”。
The iSCSI standard:
iSCSI标准：
From section 3.2 Performance/Cost:
根据第3.2节性能/成本：
MUST allow implementations to equal or improve on the current state of the art for SCSI interconnects.
必须允许实现等同于或改进SCSI互连的当前技术水平。
MUST enable cost competitive implementations.
必须支持具有成本竞争力的实施。
SHOULD minimize control overhead to enable low delay communications.
应尽量减少控制开销，以实现低延迟通信。
MUST provide high bandwidth and bandwidth aggregation.
必须提供高带宽和带宽聚合。
MUST have low host CPU utilizations, equal to or better than current technology.
必须具有较低的主机CPU利用率，等于或优于当前技术。
MUST be possible to build I/O adapters that handle the entire SCSI task.
必须能够构建处理整个SCSI任务的I/O适配器。
SHOULD permit direct data placement architectures.
应允许直接数据放置架构。
MUST NOT impose complex operations on host software.
不得对主机软件实施复杂操作。
MUST provide for full utilization of available link bandwidth.
必须充分利用可用链路带宽。
MUST allow an implementation to exploit parallelism (multiple connections) at the device interfaces and within the interconnect fabric.
必须允许实现在设备接口和互连结构内利用并行性（多个连接）。
From section 3.4 High Bandwidth/Bandwidth Aggregation:
从第3.4节高带宽/带宽聚合：
MUST operate over a single TCP connection.
必须在单个TCP连接上运行。
SHOULD support 'connection binding', and it MUST be optional to implement.
应该支持“连接绑定”，并且它必须是可选的。
From section 4 Ease of Implementation/Complexity of Protocol:
第4节协议的易实施性/复杂性：
SHOULD keep the protocol simple.
应该保持协议简单。
SHOULD minimize optional features.
应尽量减少可选功能。
MUST specify feature negotiation at session establishment (login).
必须在会话建立（登录）时指定功能协商。
MUST operate correctly when no optional features are negotiated as well as when individual option negotions are unsuccessful.
在未协商可选功能以及单个选项协商不成功时，必须正确操作。
From section 5.1 Detection of Data Corruption:
根据第5.1节数据损坏检测：
MUST support a data integrity check format for use in digest generation.
必须支持用于摘要生成的数据完整性检查格式。
MAY use separate digest for data and headers.
可以对数据和标题使用单独的摘要。
iSCSI header format SHOULD be extensible to include other data integrity digest calculation methods.
iSCSI标头格式应可扩展，以包括其他数据完整性摘要计算方法。
From section 5.2 Recovery:
从第5.2节恢复：
MUST specify mechanisms to recover in a timely fashion from failures on the initiator, target, or connecting infrastructure.
必须指定从启动器、目标或连接基础架构上的故障中及时恢复的机制。
MUST specify recovery methods for non-idempotent requests.
必须为非幂等请求指定恢复方法。
SHOULD take into account fail-over schemes for mirrored targets or highly available storage configurations.
应考虑镜像目标或高可用存储配置的故障转移方案。
SHOULD provide a method for sessions to be gracefully terminated and restarted that can be initiated by either the initiator or target.
应提供一种方法，使会话能够正常终止和重新启动，该方法可以由启动器或目标启动。
From section 6 Interoperability:
第6节互操作性：
iSCSI protocol document MUST be clear and unambiguous.
iSCSI协议文档必须清晰明确。
From section 6.1 Internet Infrastructure:
第6.1节互联网基础设施：
MUST:
-- be compatible with both IPv4 and IPv6
-- use TCP connections conservatively, keeping in mind there may
be many other users of TCP on a given machine.
MUST:
-- be compatible with both IPv4 and IPv6
-- use TCP connections conservatively, keeping in mind there may
be many other users of TCP on a given machine.
MUST NOT require changes to existing Internet protocols.
不得要求更改现有的Internet协议。
SHOULD minimize required changes to existing TCP/IP implementations.
应尽量减少对现有TCP/IP实现所需的更改。
MUST be designed to allow future substitution of SCTP (for TCP) as an IP transport protocol with minimal changes to iSCSI protocol operation, protocol data unit (PDU) structures and formats.
必须设计为允许将来将SCTP（用于TCP）替换为IP传输协议，对iSCSI协议操作、协议数据单元（PDU）结构和格式的更改最小。
From section 6.2 SCSI:
从第6.2节开始：
Any feature SAM2 requires in a valid transport mapping MUST be specified by iSCSI.
有效传输映射中SAM2需要的任何功能都必须由iSCSI指定。
MUST specify strictly ordered delivery of SCSI commands over an iSCSI session between an initiator/target pair.
必须指定通过启动器/目标对之间的iSCSI会话严格有序地传递SCSI命令。
The command ordering mechanism SHOULD seek to minimize the amount of communication necessary across multiple adapters doing transport off-load.
命令排序机制应尽量减少跨多个适配器进行负载下传输所需的通信量。
MUST specify for each feature whether it is OPTIONAL, RECOMMENDED or REQUIRED to implement and/or use.
必须为每个功能指定它是可选的、推荐的还是需要实现和/或使用的。
MUST NOT require changes to the SCSI-3 command sets and SCSI client code except except where SCSI specifications point to "transport dependent" fields and behavior.
不得要求更改SCSI-3命令集和SCSI客户端代码，除非SCSI规范指向“传输相关”字段和行为。
SHOULD track changes to SCSI and the SCSI Architecture Model.
应跟踪对SCSI和SCSI体系结构模型的更改。
MUST be capable of supporting all SCSI-3 command sets and device types.
必须能够支持所有SCSI-3命令集和设备类型。
SHOULD support ACA implementation.
应支持ACA的实施。
MUST allow for the construction of gateways to other SCSI transports
必须允许构建到其他SCSI传输的网关
MUST reliably transport SCSI commands from the initiator to the target.
必须可靠地将SCSI命令从启动器传输到目标。
MUST correctly deal with iSCSI packet drop, duplication, corruption, stale packets, and re-ordering.
必须正确处理iSCSI数据包丢失、复制、损坏、过时数据包和重新排序。
From section 7.1 Extensible Security:
从第7.1节可扩展安全性：
SHOULD require minimal configuration and overhead in the insecure operation.
在不安全的操作中，应该需要最少的配置和开销。
MUST provide for strong authentication when increased security is required.
当需要提高安全性时，必须提供强身份验证。
SHOULD allow integration of new security mechanisms without breaking backwards compatible operation.
应允许在不破坏向后兼容操作的情况下集成新的安全机制。
From section 7.2 Authentication:
从第7.2节认证：
MAY support various levels of authentication security.
可以支持不同级别的身份验证安全性。
MUST support private authenticated login.
必须支持私人身份验证登录。
iSCSI authenticated login MUST be resilient against attacks.
iSCSI身份验证登录必须能够抵御攻击。
MUST support data origin authentication of its communications; data origin authentication MAY be optional to use.
必须支持其通信的数据源认证；数据源身份验证可能是可选的。
From section 7.3 Data Integrity:
根据第7.3节数据完整性：
SHOULD NOT preclude use of additional data integrity protection protocols (IPSec, TLS).
不应排除使用其他数据完整性保护协议（IPSec、TLS）。
From section 7.4 Data Confidentiality:
根据第7.4节数据保密性：
MUST provide for the use of a data encryption protocol such as TLS or IPsec ESP to provide data confidentiality between iSCSI endpoints
必须提供数据加密协议（如TLS或IPsec ESP）的使用，以提供iSCSI端点之间的数据机密性
From section 8 Management:
第8节管理：
SHOULD be manageable using standard IP-based management protocols.
应使用基于IP的标准管理协议进行管理。
iSCSI protocol document MUST NOT define the management architecture for iSCSI, or make explicit references to management objects such as MIB variables.
iSCSI协议文档不得定义iSCSI的管理体系结构，也不得明确引用管理对象（如MIB变量）。
From section 8.1 Naming:
从第8.1节命名：
MUST support the naming architecture of SAM-2. The means by which an iSCSI resource is located MUST use or extend existing Internet standard resource location methods.
必须支持SAM-2的命名体系结构。iSCSI资源的定位方法必须使用或扩展现有的Internet标准资源定位方法。
MUST provide a means of identifying iSCSI targets by a unique identifier that is independent of the path on which it is found.
必须提供一种通过独立于找到iSCSI目标的路径的唯一标识符来标识iSCSI目标的方法。
The format for the iSCSI names MUST use existing naming authorities.
iSCSI名称的格式必须使用现有的命名权限。
An iSCSI name SHOULD be a human readable string in an international character set encoding.
iSCSI名称应为国际字符集编码中的人类可读字符串。
Standard Internet lookup services SHOULD be used to resolve iSCSI names.
应使用标准Internet查找服务解析iSCSI名称。
SHOULD deal with the complications of the new SCSI security architecture.
应处理新SCSI安全体系结构的复杂性。
iSCSI naming architecture MUST address support of SCSI 3rd party operations such as EXTENDED COPY.
iSCSI命名体系结构必须支持SCSI第三方操作，如扩展拷贝。
From section 8.2 Discovery:
从第8.2节发现：
MUST have no impact on the use of current IP network discovery techniques.
不得影响当前IP网络发现技术的使用。
MUST provide some means of determining whether an iSCSI service is available through an IP address.
必须提供某种方法来确定iSCSI服务是否可通过IP地址使用。
SCSI protocol-dependent techniques SHOULD be used for further discovery beyond the iSCSI layer.
SCSI协议相关技术应用于iSCSI层之外的进一步发现。
MUST provide a method of discovering, given an IP end point on its well-known port, the list of SCSI targets available to the requestor. The use of this discovery service MUST be optional.
必须提供一种方法，在已知端口上给定IP端点的情况下，发现可供请求者使用的SCSI目标列表。此发现服务的使用必须是可选的。
From section 9 Internet Accessability.
来自第9节互联网可访问性。
SHOULD be scrutinized for denial of service issues and they should be addressed.
应仔细检查拒绝服务问题，并解决这些问题。
From section 9.2 Firewalls and Proxy Servers
来自第9.2节防火墙和代理服务器
SHOULD allow deployment where functional and optimizing middle-boxes such as firewalls, proxy servers and NATs are present.
应允许在防火墙、代理服务器和NAT等具有功能和优化的中间盒的位置进行部署。
use of IP addresses and TCP ports SHOULD be firewall friendly.
IP地址和TCP端口的使用应该是防火墙友好的。
From section 9.3 Congestion Control and Transport Selection
来自第9.3节拥塞控制和运输选择
MUST be a good network citizen with TCP-compatible congestion control (as defined in [RFC2914]).
必须是具有TCP兼容拥塞控制（如[RFC2914]中所定义）的良好网络公民。
iSCSI implementations MUST NOT use multiple connections as a means to avoid transport-layer congestion control.
iSCSI实施不得使用多个连接作为避免传输层拥塞控制的手段。
Traditionally, storage controllers (e.g., disk array controllers, tape library controllers) have supported the SCSI-3 protocol and have been attached to computers by SCSI parallel bus or Fibre Channel.
传统上，存储控制器（如磁盘阵列控制器、磁带库控制器）支持SCSI-3协议，并通过SCSI并行总线或光纤通道连接到计算机。
The IP infrastructure offers compelling advantages for volume/ block-oriented storage attachment. It offers the opportunity to take advantage of the performance/cost benefits provided by competition in the Internet marketplace. This could reduce the cost of storage network infrastructure by providing economies arising from the need to install and operate only a single type of network.
IP基础架构为面向卷/块的存储连接提供了引人注目的优势。它提供了利用互联网市场竞争带来的性能/成本优势的机会。这可以降低存储网络基础架构的成本，因为只需要安装和运行单一类型的网络就可以节省成本。
In addition, the IP protocol suite offers the opportunity for a rich array of management, security and QoS solutions. Organizations may initially choose to operate storage networks based on iSCSI that are independent of (isolated from) their current data networks except for secure routing of storage management traffic. These organizations anticipated benefits from the high performance/cost of IP equipment and the opportunity for a unified management architecture. As security and QoS evolve, it becomes reasonable to build combined networks with shared infrastructure; nevertheless, it is likely that sophisticated users will choose to keep their storage sub-networks isolated to afford the best control of security and QoS to ensure a high-performance environment tuned to storage traffic.
此外，IP协议套件还提供了一系列丰富的管理、安全和QoS解决方案。企业最初可能会选择基于iSCSI的存储网络，这些存储网络独立于（与）其当前数据网络隔离，但存储管理流量的安全路由除外。这些组织预计IP设备的高性能/成本以及统一管理体系结构的机会将带来好处。随着安全性和QoS的发展，构建具有共享基础设施的组合网络变得合理；然而，经验丰富的用户可能会选择保持其存储子网络的隔离，以提供对安全性和QoS的最佳控制，从而确保高性能环境能够适应存储流量。
Mapping SCSI over IP also provides:
通过IP映射SCSI还提供：
-- Extended distance ranges
-- Connectivity to "carrier class" services that support IP
-- Extended distance ranges
-- Connectivity to "carrier class" services that support IP
The following applications for iSCSI are contemplated:
考虑了以下iSCSI应用程序：
-- Local storage access, consolidation, clustering and pooling (as
in the data center)
-- Network client access to remote storage (eg. a "storage service
provider")
-- Local and remote synchronous and asynchronous mirroring between
storage controllers
-- Local and remote backup and recovery
-- Local storage access, consolidation, clustering and pooling (as
in the data center)
-- Network client access to remote storage (eg. a "storage service
provider")
-- Local and remote synchronous and asynchronous mirroring between
storage controllers
-- Local and remote backup and recovery
iSCSI will support the following topologies:
iSCSI将支持以下拓扑：
-- Point-to-point direct connections
-- Dedicated storage LAN, consisting of one or more LAN segments
-- Shared LAN, carrying a mix of traditional LAN traffic plus
storage traffic
-- LAN-to-WAN extension using IP routers or carrier-provided "IP
Datatone"
-- Private networks and the public Internet
-- Point-to-point direct connections
-- Dedicated storage LAN, consisting of one or more LAN segments
-- Shared LAN, carrying a mix of traditional LAN traffic plus
storage traffic
-- LAN-to-WAN extension using IP routers or carrier-provided "IP
Datatone"
-- Private networks and the public Internet
IP LAN-WAN routers may be used to extend the IP storage network to the wide area, permitting remote disk access (as for a storage utility), synchronous and asynchronous remote mirroring, and remote
IP LAN-WAN路由器可用于将IP存储网络扩展到广域，允许远程磁盘访问（对于存储实用程序）、同步和异步远程镜像以及远程访问
backup and restore (as for tape vaulting). In the WAN, using TCP end-to-end avoids the need for specialized equipment for protocol conversion, ensures data reliability, copes with network congestion, and provides retransmission strategies adapted to WAN delays.
备份和恢复（如磁带保险存储）。在广域网中，使用TCP端到端避免了对协议转换专用设备的需要，确保了数据的可靠性，应对了网络拥塞，并提供了适应广域网延迟的重传策略。
The iSCSI technology deployment will involve the following elements:
iSCSI技术部署将涉及以下要素：
(1) Conclusion of a complete protocol standard and supporting implementations; (2) Development of Ethernet storage NICs and related driver and protocol software; [NOTE: high-speed applications of iSCSI are expected to require significant portions of the iSCSI/TCP/IP implementation in hardware to achieve the necessary throughput.] (3) Development of compatible storage controllers; and (4) The likely development of translating gateways to provide connectivity between the Ethernet storage network and the Fibre Channel and/or parallel-bus SCSI domains. (5) Development of specifications for iSCSI device management such as MIBs, LDAP or XML schemas, etc. (6) Development of management and directory service applications to support a robust SAN infrastructure.
(1) 制定完整的协议标准并支持实施；（2） 以太网存储网卡及相关驱动和协议软件的开发；[注：iSCSI的高速应用预计需要在硬件中实现iSCSI/TCP/IP的大部分，以实现必要的吞吐量。]（3）开发兼容的存储控制器；（4）可能开发转换网关，以提供以太网存储网络与光纤通道和/或并行总线SCSI域之间的连接。（5） 开发iSCSI设备管理规范，如MIB、LDAP或XML模式等。（6）开发管理和目录服务应用程序，以支持强健的SAN基础架构。
Products could initially be offered for Gigabit Ethernet attachment, with rapid migration to 10 GbE. For performance competitive with alternative SCSI transports, it will be necessary to implement the performance path of the full protocol stack in hardware. These new storage NICs might perform full-stack processing of a complete SCSI task, analogous to today's SCSI and Fibre Channel HBAs, and might also support all host protocols that use TCP (NFS, CIFS, HTTP, etc).
产品最初可用于千兆以太网连接，并可快速迁移到10GbE。为了使性能与其他SCSI传输相竞争，有必要在硬件中实现完整协议栈的性能路径。这些新的存储NIC可能会执行完整SCSI任务的全堆栈处理，类似于今天的SCSI和光纤通道HBA，还可能支持使用TCP的所有主机协议（NFS、CIFS、HTTP等）。
The charter of the IETF IP Storage Working Group (IPSWG) describes the broad goal of mapping SCSI to IP using a transport that has proven congestion avoidance behavior and broad implementation on a variety of platforms. Within that broad charter, several transport alternatives may be considered. Initial IPS work focuses on TCP, and this requirements document is restricted to that domain of interest.
IETF IP存储工作组（IPSWG）的章程描述了使用一种传输将SCSI映射到IP的广泛目标，该传输已在各种平台上证明了拥塞避免行为和广泛的实现。在这一广泛的宪章范围内，可以考虑几种运输备选方案。最初的IPS工作集中在TCP上，本需求文档仅限于感兴趣的领域。
In general, iSCSI MUST allow implementations to equal or improve on the current state of the art for SCSI interconnects. This goal breaks down into several types of requirement:
通常，iSCSI必须允许实现与SCSI互连的当前技术水平相同或有所改进。该目标分为几类需求：
Cost competitive with alternative storage network technologies:
与其他存储网络技术相比具有成本竞争力：
In order to be adopted by vendors and the user community, the iSCSI protocol MUST enable cost competitive implementations when compared to other SCSI transports (Fibre Channel).
为了被供应商和用户群体采用，iSCSI协议必须能够实现与其他SCSI传输（光纤通道）相比具有成本竞争力的实施。
Low delay communication:
低延迟通信：
Conventional storage access is of a stop-and-wait remote procedure call type. Applications typically employ very little pipelining of their storage accesses, and so storage access delay directly impacts performance. The delay imposed by current storage interconnects, including protocol processing, is generally in the range of 100 microseconds. The use of caching in storage controllers means that many storage accesses complete almost instantly, and so the delay of the interconnect can have a high relative impact on overall performance. When stop-and-wait IO is used, the delay of the interconnect will affect performance. The iSCSI protocol SHOULD minimize control overhead, which adds to delay.
传统的存储访问是停止和等待远程过程调用类型。应用程序通常很少使用存储访问的流水线，因此存储访问延迟直接影响性能。当前存储互连（包括协议处理）施加的延迟通常在100微秒范围内。在存储控制器中使用缓存意味着许多存储访问几乎立即完成，因此互连的延迟会对总体性能产生较大的相对影响。使用停止和等待IO时，互连延迟将影响性能。iSCSI协议应将增加延迟的控制开销降至最低。
Low host CPU utilization, equal to or better than current technology:
主机CPU利用率低，等于或优于当前技术：
For competitive performance, the iSCSI protocol MUST allow three key implementation goals to be realized:
为了获得有竞争力的性能，iSCSI协议必须允许实现三个关键的实施目标：
(1) iSCSI MUST make it possible to build I/O adapters that handle an entire SCSI task, as alternative SCSI transport implementations do. (2) The protocol SHOULD permit direct data placement ("zero-copy" memory architectures, where the I/O adapter reads or writes host memory exactly once per disk transaction. (3) The protocol SHOULD NOT impose complex operations on the host software, which would increase host instruction path length relative to alternatives.
(1) iSCSI必须能够像其他SCSI传输实现一样，构建处理整个SCSI任务的I/O适配器。（2） 协议应允许直接数据放置（“零拷贝”内存体系结构，其中I/O适配器在每个磁盘事务中只读取或写入主机内存一次。（3）协议不应在主机软件上施加复杂操作，这将增加主机指令路径长度。
Direct data placement (zero-copy iSCSI):
直接数据放置（零拷贝iSCSI）：
Direct data placement refers to iSCSI data being placed directly "off the wire" into the allocated location in memory with no intermediate copies. Direct data placement significantly reduces the memory bus and I/O bus loading in the endpoint systems, allowing improved performance. It reduces the memory required for NICs, possibly reducing the cost of these solutions.
直接数据放置是指将iSCSI数据直接“离线”放置到内存中的分配位置，而无需中间副本。直接数据放置显著减少了端点系统中的内存总线和I/O总线负载，从而提高了性能。它减少了NIC所需的内存，可能降低了这些解决方案的成本。
This is an important implementation goal. In an iSCSI system, each of the end nodes (for example host computer and storage controller) should have ample memory, but the intervening nodes (NIC, switches) typically will not.
这是一个重要的实施目标。在iSCSI系统中，每个终端节点（例如主机和存储控制器）都应具有足够的内存，但中间节点（NIC、交换机）通常不会。
High bandwidth, bandwidth aggregation:
高带宽、带宽聚合：
The bandwidth (transfer rate, MB/sec) supported by storage controllers is rapidly increasing, due to several factors:
由于以下几个因素，存储控制器支持的带宽（传输速率，MB/秒）正在迅速增加：
1. Increase in disk spindle and controller performance; 2. Use of ever-larger caches, and improved caching algorithms; 3. Increased scale of storage controllers (number of supported spindles, speed of interconnects).
1. 提高磁盘主轴和控制器性能；2.使用更大的缓存和改进的缓存算法；3.增加了存储控制器的规模（支持的心轴数量、互连速度）。
The iSCSI protocol MUST provide for full utilization of available link bandwidth. The protocol MUST also allow an implementation to exploit parallelism (multiple connections) at the device interfaces and within the interconnect fabric.
iSCSI协议必须充分利用可用链路带宽。协议还必须允许实现在设备接口和互连结构内利用并行性（多个连接）。
The next two sections further discuss the need for direct data placement and high bandwidth.
接下来的两节将进一步讨论直接数据放置和高带宽的需求。
Framing refers to the addition of information in a header, or the data stream to allow implementations to locate the boundaries of an iSCSI protocol data unit (PDU) within the TCP byte stream. There are two technical requirements driving framing: interfacing needs, and accelerated processing needs.
帧是指在报头或数据流中添加信息，以允许实现在TCP字节流中定位iSCSI协议数据单元（PDU）的边界。有两个技术要求驱动框架：接口需求和加速处理需求。
A framing solution that addresses the "interfacing needs" of the iSCSI protocol will facilitate the implementation of a message-based upper layer protocol (iSCSI) on top of an underlying byte streaming protocol (TCP). Since TCP is a reliable transport, this can be accomplished by including a length field in the iSCSI header. Finding the protocol frame assumes that the receiver will parse from the beginning of the TCP data stream, and never make a mistake (lose alignment on packet headers).
解决iSCSI协议“接口需求”的帧解决方案将有助于在底层字节流协议（TCP）的基础上实现基于消息的上层协议（iSCSI）。由于TCP是一种可靠的传输，因此可以通过在iSCSI标头中包含长度字段来实现。查找协议帧假定接收方将从TCP数据流的开始解析，并且从不出错（在数据包头上丢失对齐）。
The other technical requirement for framing, "accelerated processing", stems from the need to handle increasingly higher data rates in the physical media interface. Two needs arise from higher data rates:
帧的另一项技术要求“加速处理”，源于需要在物理媒体接口中处理越来越高的数据速率。更高的数据速率带来了两种需求：
(1) LAN environment - NIC vendors seek ways to provide "zero-copy" methods of moving data directly from the wire into application buffers.
(1) LAN环境—NIC供应商寻求提供“零拷贝”方法，将数据直接从线路移动到应用程序缓冲区。
(2) WAN environment- the emergence of high bandwidth, high latency, low bit error rate physical media places huge buffer requirements on the physical interface solutions.
(2) WAN环境—高带宽、高延迟、低误码率物理介质的出现对物理接口解决方案提出了巨大的缓冲要求。
First, vendors are producing network processing hardware that offloads network protocols to hardware solutions to achieve higher data rates. The concept of "zero-copy" seeks to store blocks of data in appropriate memory locations (aligned) directly off the wire, even when data is reordered due to packet loss. This is necessary to drive actual data rates of 10 Gigabit/sec and beyond.
首先，供应商正在生产网络处理硬件，将网络协议转移到硬件解决方案，以实现更高的数据速率。“零拷贝”的概念旨在将数据块直接离线存储在适当的内存位置（对齐），即使数据因数据包丢失而重新排序。这对于驱动10千兆位/秒及以上的实际数据速率是必要的。
Secondly, in order for iSCSI to be successful in the WAN arena it must be possible to operate efficiently in high bandwidth, high delay networks. The emergence of multi-gigabit IP networks with latencies in the tens to hundreds of milliseconds presents a challenge. To fill such large pipes, it is necessary to have tens of megabytes of outstanding requests from the application. In addition, some protocols potentially require tens of megabytes at the transport layer to deal with buffering for reassembly of data when packets are received out-of-order.
其次，为了使iSCSI在广域网领域取得成功，必须能够在高带宽、高延迟网络中高效运行。延迟在数十到数百毫秒之间的千兆IP网络的出现是一个挑战。要填充如此大的管道，应用程序必须有数十兆字节的未完成请求。此外，一些协议可能需要传输层数十兆字节来处理缓冲，以便在数据包被无序接收时重新组装数据。
In both cases, the issue is the desire to minimize the amount of memory and memory bandwidth required for iSCSI hardware solutions.
在这两种情况下，问题都是希望将iSCSI硬件解决方案所需的内存量和内存带宽降至最低。
Consider that a network pipe at 10 Gbps x 200 msec holds 250 MB. [Assume land-based communication with a spot half way around the world at the equator. Ignore additional distance due to cable routing. Ignore repeater and switching delays; consider only a speed-of-light delay of 5 microsec/km. The circumference of the globe at the equator is approx. 40000 km (round-trip delay must be considered to keep the pipe full). 10 Gb/sec x 40000 km x 5 microsec/km x B / 8b = 250 MB]. In a conventional TCP implementation, loss of a TCP segment means that stream processing MUST stop until that segment is recovered, which takes at least a time of <network round trip> to accomplish. Following the example above, an implementation would be obliged to catch 250 MB of data into an anonymous buffer before resuming stream processing; later, this data would need to be moved to its proper location. Some proponents of iSCSI seek some means of putting data directly where it belongs, and avoiding extra data movement in the case of segment drop. This is a key concept in understanding the debate behind framing methodologies.
考虑在10 Gbps×200毫秒的网络管道保持250毫巴。[假设地球在赤道附近有一个地点在半个地球上通信。忽略由于电缆路由而造成的额外距离。忽略中继器和切换延迟；只考虑5毫秒/公里的光延迟速度。地球赤道附近的周长大约为40000公里。（必须考虑往返延迟以保持管道充满）。10 Gb/sec x 40000 km x 5 microsec/km x B/8b=250 MB]。在传统TCP实现中，丢失TCP段意味着流处理必须停止，直到该段恢复，这至少需要一段时间<网络往返>。按照上述示例，实现必须在恢复流处理之前将250 MB的数据捕获到匿名缓冲区中；稍后，这些数据将需要移动到其适当的位置。iSCSI的一些支持者寻求一些方法，将数据直接放在其所属的位置，并在数据段丢失的情况下避免额外的数据移动。这是理解框架方法背后争论的一个关键概念。
The framing of the iSCSI protocol impacts both the "interfacing needs" and the "accelerated processing needs", however, while including a length in a header may suffice for the "interfacing needs", it will not serve the direct data placement needs. The framing mechanism developed should allow resynchronization of packet boundaries even in the case where a packet is temporarily missing in the incoming data stream.
iSCSI协议的框架同时影响“接口需求”和“加速处理需求”，但是，尽管在报头中包含长度可能足以满足“接口需求”，但它不能满足直接数据放置需求。开发的成帧机制应允许分组边界的重新同步，即使在传入数据流中暂时丢失分组的情况下也是如此。
At today's block storage transport throughput, any single link can be saturated by the volume of storage traffic. Scientific data applications and data replication are examples of storage applications that push the limits of throughput.
在今天的块存储传输吞吐量下，任何单个链路都可能被存储通信量饱和。科学数据应用程序和数据复制是突破吞吐量限制的存储应用程序的例子。
Some applications, such as log updates, streaming tape, and replication, require ordering of updates and thus ordering of SCSI commands. An initiator may maintain ordering by waiting for each update to complete before issuing the next (a.k.a. synchronous updates). However, the throughput of synchronous updates decreases inversely with increases in network distances.
某些应用程序（如日志更新、流式磁带和复制）需要对更新进行排序，从而对SCSI命令进行排序。发起者可以通过在发布下一个更新（又称同步更新）之前等待每个更新完成来维持顺序。然而，同步更新的吞吐量随着网络距离的增加而反向下降。
For greater throughput, the SCSI task queuing mechanism allows an initiator to have multiple commands outstanding at the target simultaneously and to express ordering constraints on the execution of those commands. The task queuing mechanism is only effective if the commands arrive at the target in the order they were presented to the initiator (FIFO order). The iSCSI standard must provide an ordered transport of SCSI commands, even when commands are sent along different network paths (see Section 5.2 SCSI). This is referred to as "command ordering".
为了获得更大的吞吐量，SCSI任务队列机制允许启动器同时在目标上有多个未完成的命令，并表示这些命令执行的顺序约束。任务队列机制只有在命令按照其提交给启动器的顺序（FIFO顺序）到达目标时才有效。iSCSI标准必须提供SCSI命令的有序传输，即使命令沿不同的网络路径发送（请参阅第5.2节SCSI）。这被称为“命令排序”。
The iSCSI protocol MUST operate over a single TCP connection to accommodate lower cost implementations. To enable higher performance storage devices, the protocol should specify a means to allow operation over multiple connections while maintaining the behavior of a single SCSI port. This would allow the initiator and target to use multiple network interfaces and multiple paths through the network for increased throughput. There are a few potential ways to satisfy the multiple path and ordering requirements.
iSCSI协议必须在单个TCP连接上运行，以适应低成本实施。要启用更高性能的存储设备，协议应指定一种方法，允许在保持单个SCSI端口行为的同时通过多个连接进行操作。这将允许发起方和目标方通过网络使用多个网络接口和多条路径来提高吞吐量。有几种潜在的方法可以满足多路径和订购需求。
A popular way to satisfy the multiple-path requirement is to have a driver above the SCSI layer instantiate multiple copies of the SCSI transport, each communicating to the target along a different path. "Wedge" drivers use this technique today to attain high performance. Unfortunately, wedge drivers must wait for acknowledgement of completion of each request (stop-and-wait) to ensure ordered updates.
满足多路径需求的一种常用方法是让SCSI层之上的驱动程序实例化SCSI传输的多个副本，每个副本都通过不同的路径与目标通信。“楔形”驱动器今天使用这种技术来实现高性能。不幸的是，楔形驱动程序必须等待每个请求的完成确认（停止和等待），以确保有序更新。
Another approach might be for iSCSI protocol to use multiple instances of its underlying transport (e.g. TCP). The iSCSI layer would make these independent transport instances appear as one SCSI transport instance and maintain the ability to do ordered SCSI command queuing. The document will refer to this technique as "connection binding" for convenience.
另一种方法可能是iSCSI协议使用其底层传输的多个实例（例如TCP）。iSCSI层将使这些独立的传输实例显示为一个SCSI传输实例，并保持执行有序SCSI命令队列的能力。为了方便起见，本文将这种技术称为“连接绑定”。
The iSCSI protocol SHOULD support connection binding, and it MUST be optional to implement.
iSCSI协议应支持连接绑定，并且必须是可选的。
In the presence of connection binding, there are two ways to assign features to connections. In the symmetric approach, all the connections are identical from a feature standpoint. In the asymmetric model, connections have different features. For example, some connections may be used primarily for data transfers whereas others are used primarily for SCSI commands.
在存在连接绑定的情况下，有两种方法可以将特征指定给连接。在对称方法中，从特征的角度来看，所有连接都是相同的。在非对称模型中，连接具有不同的特征。例如，某些连接可能主要用于数据传输，而其他连接则主要用于SCSI命令。
Since the iSCSI protocol must support the case where there was only one transport connection, the protocol must have command, data, and status travel over the same connection.
由于iSCSI协议必须支持只有一个传输连接的情况，因此协议必须在同一连接上具有命令、数据和状态传输。
In the case of multiple connections, the iSCSI protocol must keep the command and its associated data and status on the same connection (connection allegiance). Sending data and status on the same connection is desirable because this guarantees that status is received after the data (TCP provides ordered delivery). In the case where each connection is managed by a separate processor, allegiance decreases the need for inter-processor communication. This symmetric approach is a natural extension of the single connection approach.
在多个连接的情况下，iSCSI协议必须将命令及其关联的数据和状态保持在同一个连接上（连接忠诚）。在同一个连接上发送数据和状态是可取的，因为这可以保证状态在数据发送后被接收（TCP提供有序传递）。在每个连接由单独的处理器管理的情况下，忠诚减少了处理器间通信的需要。这种对称方法是单连接方法的自然扩展。
An alternate approach that was extensively discussed involved sending all commands on a single connection and the associated data and status on a different connection (asymmetric approach). In this scheme, the transport ensures the commands arrive in order. The protocol on the data and status connections is simpler, perhaps lending itself to a simpler realization in hardware. One disadvantage of this approach is that the recovery procedure is different if a command connection fails vs. a data connection. Some argued that this approach would require greater inter-processor communication when connections are spread across processors.
广泛讨论的另一种方法涉及在单个连接上发送所有命令以及在不同连接上发送相关数据和状态（非对称方法）。在该方案中，传输确保命令有序到达。关于数据和状态连接的协议更简单，可能有助于在硬件中实现更简单的功能。这种方法的一个缺点是，如果命令连接失败，恢复过程与数据连接不同。一些人认为，当连接分布在处理器之间时，这种方法需要更大的处理器间通信。
The reader may reference the mail archives of the IPS mailing list between June and September of 2000 for extensive discussions on symmetric vs asymmetric connection models.
读者可参考2000年6月至9月期间IPS邮件列表的邮件档案，以广泛讨论对称与非对称连接模型。
Experience has shown that adoption of a protocol by the Internet community is inversely proportional to its complexity. In addition, the simpler the protocol, the easier it is to diagnose problems. The designers of iSCSI SHOULD strive to fulfill the requirements of the creating a SCSI transport over IP, while keeping the protocol as simple as possible.
经验表明，互联网社区采用协议与其复杂性成反比。此外，协议越简单，诊断问题就越容易。iSCSI的设计者应该努力满足通过IP创建SCSI传输的要求，同时使协议尽可能简单。
In the interest of simplicity, iSCSI SHOULD minimize optional features. When features are deemed necessary, the protocol MUST specify feature negotiation at session establishment (login). The iSCSI transport MUST operate correctly when no optional features are negotiated as well as when individual option negotiations are unsuccessful.
为了简单起见，iSCSI应尽量减少可选功能。当认为需要特性时，协议必须在会话建立（登录）时指定特性协商。当未协商任何可选功能以及单个选项协商不成功时，iSCSI传输必须正常运行。
There have been several research papers that suggest that the TCP checksum calculation allows a certain number of bit errors to pass undetected [10] [11].
有几篇研究论文表明，TCP校验和计算允许一定数量的位错误通过而未被检测[10][11]。
In order to protect against data corruption, the iSCSI protocol MUST support a data integrity check format for use in digest generation.
为了防止数据损坏，iSCSI协议必须支持用于摘要生成的数据完整性检查格式。
The iSCSI protocol MAY use separate digests for data and headers. In an iSCSI proxy or gateway situation, the iSCSI headers are removed and re-built, and the TCP stream is terminated on either side. This means that even the TCP checksum is removed and recomputed within the gateway. To ensure the protection of commands, data, and status the iSCSI protocol MUST include a CRC or other digest mechanism that is computed on the SCSI data block itself, as well as on each command and status message. Since gateways may strip iSCSI headers and rebuild them, a separate header CRC is required. Two header digests, one for invariant portions of the header (addresses) and one for the variant portion would provide protection against changes to portions of the header that should never be changed by middle boxes (eg, addresses).
iSCSI协议可以对数据和头使用单独的摘要。在iSCSI代理或网关情况下，iSCSI标头将被删除并重新构建，TCP流将在任一侧终止。这意味着即使是TCP校验和也会被删除并在网关内重新计算。为了确保对命令、数据和状态的保护，iSCSI协议必须包括一个CRC或其他摘要机制，该机制是在SCSI数据块本身以及每个命令和状态消息上计算的。由于网关可能会剥离iSCSI标头并重建它们，因此需要单独的标头CRC。两个标题摘要，一个用于标题的不变部分（地址），另一个用于变体部分，可以防止中间框（例如地址）永远不会更改标题部分的更改。
The iSCSI header format SHOULD be extensible to include other digest calculation methods.
iSCSI标头格式应可扩展，以包括其他摘要计算方法。
The SCSI protocol was originally designed for a parallel bus transport that was highly reliable. SCSI applications tend to assume that transport errors never happen, and when they do, SCSI application recovery tends to be expensive in terms of time and computational resources.
SCSI协议最初是为高度可靠的并行总线传输而设计的。SCSI应用程序倾向于假设传输错误永远不会发生，如果发生，SCSI应用程序恢复在时间和计算资源方面往往代价高昂。
iSCSI protocol design, while placing an emphasis on simplicity, MUST lead to timely recovery from failure of initiator, target, or connecting network infrastructure (cabling, data path equipment such as routers, etc).
iSCSI协议设计在强调简单性的同时，必须能够及时从启动器、目标或连接网络基础设施（布线、路由器等数据路径设备）的故障中恢复。
iSCSI MUST specify recovery methods for non-idempotent requests, such as operations on tape drives.
iSCSI必须为非幂等请求（如磁带机上的操作）指定恢复方法。
The iSCSI protocol error recover mechanism SHOULD take into account fail-over schemes for mirrored targets or highly available storage configurations that provide paths to target data through multiple "storage servers". This would provide a basis for layered technologies like high availability and clustering.
iSCSI协议错误恢复机制应考虑镜像目标的故障转移方案，或通过多个“存储服务器”提供目标数据路径的高可用存储配置。这将为高可用性和集群等分层技术提供基础。
The iSCSI protocol SHOULD also provide a method for sessions to be gracefully terminated and restarted that can be initiated by either the initiator or target. This provides the ability to gracefully fail over an initiator or target, or reset a target after performing maintenance tasks such as upgrading software.
iSCSI协议还应提供一种方法，使会话能够正常终止和重新启动，该方法可以由启动器或目标启动。这提供了在执行维护任务（如升级软件）后正常故障转移启动器或目标或重置目标的能力。
It must be possible for initiators and targets that implement the required portions of the iSCSI specification to interoperate. While this requirement is so obvious that it doesn't seem worth mentioning, if the protocol specification contains ambiguous wording, different implementations may not interoperate. The iSCSI protocol document MUST be clear and unambiguous.
实现iSCSI规范所需部分的启动器和目标必须能够进行互操作。虽然这一要求显而易见，似乎不值得一提，但如果协议规范包含模棱两可的措辞，不同的实现可能无法互操作。iSCSI协议文档必须清晰明确。
The iSCSI protocol MUST:
iSCSI协议必须：
-- be compatible with both IPv4 and IPv6.
-- use TCP connections conservatively, keeping in mind there may
be many other users of TCP on a given machine.
-- be compatible with both IPv4 and IPv6.
-- use TCP connections conservatively, keeping in mind there may
be many other users of TCP on a given machine.
The iSCSI protocol MUST NOT require changes to existing Internet protocols and SHOULD minimize required changes to existing TCP/IP implementations.
iSCSI协议不得要求对现有Internet协议进行更改，并应尽量减少对现有TCP/IP实施所需的更改。
iSCSI MUST be designed to allow future substitution of SCTP (for TCP) as an IP transport protocol with minimal changes to iSCSI protocol operation, protocol data unit (PDU) structures and formats. Although not widely implemented today, SCTP has many design features that make it a desirable choice for future iSCSI enhancement.
iSCSI的设计必须允许将来将SCTP（用于TCP）替换为IP传输协议，而对iSCSI协议操作、协议数据单元（PDU）结构和格式的更改最少。尽管目前尚未广泛实施，但SCTP具有许多设计功能，使其成为未来iSCSI增强的理想选择。
In order to be considered a SCSI transport, the iSCSI standard must comply with the requirements of the SCSI Architecture Model [SAM-2] for a SCSI transport. Any feature SAM2 requires in a valid transport mapping MUST be specified by iSCSI. The iSCSI protocol document MUST
为了被视为SCSI传输，iSCSI标准必须符合SCSI传输的SCSI体系结构模型[SAM-2]的要求。有效传输映射中SAM2需要的任何功能都必须由iSCSI指定。必须提供iSCSI协议文档
specify for each feature whether it is OPTIONAL, RECOMMENDED or REQUIRED to implement and/or use.
为每个功能指定它是可选的、推荐的还是需要实现和/或使用的。
The SCSI Architectural Model [SAM-2] indicates an expectation that the SCSI transport provides ordering of commands on an initiator target-LUN granularity. There has been much discussion on the IPS reflector and in working group meetings regarding the means to ensure this ordering. The rough consensus is that iSCSI MUST specify strictly ordered delivery of SCSI commands over an iSCSI session between an initiator/target pair, even in the presence of transport errors. This command ordering mechanism SHOULD seek to minimize the amount of communication necessary across multiple adapters doing transport off-load. If an iSCSI implementation does not require ordering it can instantiate multiple sessions per initiator-target pair.
SCSI体系结构模型[SAM-2]表示SCSI传输在启动器目标LUN粒度上提供命令排序的期望。在IPS反射器和工作组会议上，就确保订购的方法进行了大量讨论。大致的共识是，iSCSI必须在启动器/目标对之间的iSCSI会话上指定SCSI命令的严格有序传递，即使在存在传输错误的情况下也是如此。此命令排序机制应尽量减少跨多个适配器进行负载下传输所需的通信量。如果iSCSI实施不需要排序，它可以为每个启动器目标对实例化多个会话。
iSCSI is intended to be a new SCSI "transport" [SAM2]. As a mapping of SCSI over TCP, iSCSI requires interaction with both T10 and IETF. However, the iSCSI protocol MUST NOT require changes to the SCSI-3 command sets and SCSI client code except where SCSI specifications point to "transport dependent" fields and behavior. For example, changes to SCSI documents will be necessary to reflect lengthier iSCSI target names and potentially lengthier timeouts. Collaboration with T10 will be necessary to achieve this requirement.
iSCSI旨在成为一种新的SCSI“传输”[SAM2]。作为SCSI在TCP上的映射，iSCSI需要与T10和IETF进行交互。但是，iSCSI协议不得要求更改SCSI-3命令集和SCSI客户端代码，除非SCSI规范指向“传输相关”字段和行为。例如，需要更改SCSI文档以反映更长的iSCSI目标名称和可能更长的超时。为了达到这一要求，必须与T10合作。
The iSCSI protocol SHOULD track changes to SCSI and the SCSI Architecture Model.
iSCSI协议应跟踪对SCSI和SCSI体系结构模型的更改。
The iSCSI protocol MUST be capable of supporting all SCSI-3 command sets and device types. The primary focus is on supporting 'larger' devices: host computers and storage controllers (disk arrays, tape libraries). However, other command sets (printers, scanners) must be supported. These requirements MUST NOT be construed to mean that iSCSI must be natively implementable on all of today's SCSI devices, which might have limited processing power or memory.
iSCSI协议必须能够支持所有SCSI-3命令集和设备类型。主要重点是支持“更大”的设备：主机和存储控制器（磁盘阵列、磁带库）。但是，必须支持其他命令集（打印机、扫描仪）。这些要求决不能被理解为意味着iSCSI必须能够在今天的所有SCSI设备上以本机方式实现，因为这些设备可能具有有限的处理能力或内存。
ACA (Auto Contingent Allegiance) is an optional SCSI mechanism that stops execution of a sequence of dependent SCSI commands when one of them fails. The situation surrounding it is complex - T10 specifies ACA in SAM2, and hence iSCSI must support it and endeavor to make sure that ACA gets implemented sufficiently (two independent interoperable implementations) to avoid dropping ACA in the transition from Proposed Standard to Draft Standard. This implies iSCSI SHOULD support ACA implementation.
ACA（自动或有效忠）是一种可选的SCSI机制，当其中一个SCSI命令失败时，它会停止执行一系列相关SCSI命令。围绕它的情况很复杂—T10在SAM2中指定了ACA，因此iSCSI必须支持它，并努力确保ACA得到充分实施（两个独立的可互操作实施），以避免在从建议的标准过渡到草案标准时丢弃ACA。这意味着iSCSI应支持ACA实施。
The iSCSI protocol MUST allow for the construction of gateways to other SCSI transports, including parallel SCSI [SPI-X] and to SCSI FCP[FCP, FCP-2]. It MUST be possible to construct "translating"
iSCSI协议必须允许构建到其他SCSI传输的网关，包括并行SCSI[SPI-X]和到SCSI FCP[FCP，FCP-2]的网关。“翻译”必须是可能的
gateways so that iSCSI hosts can interoperate with SCSI-X devices; so that SCSI-X devices can communicate over an iSCSI network; and so that SCSI-X hosts can use iSCSI targets (where SCSI-X refers to parallel SCSI, SCSI-FCP, or SCSI over any other transport). This requirement is implied by support for SAM-2, but is worthy of emphasis. These are true application protocol gateways, and not just bridge/routers. The different standards have only the SCSI-3 command set layer in common. These gateways are not mere packet forwarders.
网关，使iSCSI主机可以与SCSI-X设备互操作；使SCSI-X设备可以通过iSCSI网络进行通信；这样SCSI-X主机就可以使用iSCSI目标（其中SCSI-X指的是并行SCSI、SCSI-FCP或任何其他传输上的SCSI）。对SAM-2的支持暗示了这一要求，但值得强调。这些是真正的应用程序协议网关，而不仅仅是网桥/路由器。不同的标准只有SCSI-3命令集层是相同的。这些网关不仅仅是数据包转发器。
The iSCSI protocol MUST reliably transport SCSI commands from the initiator to the target. According to [SAM-2, p. 17.] "The function of the service delivery subsystem is to transport an error-free copy of the request or response between the sender and the receiver" [SAM-2, p. 22]. The iSCSI protocol MUST correctly deal with iSCSI packet drop, duplication, corruption, stale packets, and re-ordering.
iSCSI协议必须可靠地将SCSI命令从启动器传输到目标。根据[SAM-2，第17页]“服务交付子系统的功能是在发送方和接收方之间传输请求或响应的无错误副本”[SAM-2，第22页]。iSCSI协议必须正确处理iSCSI数据包丢失、复制、损坏、过时数据包和重新排序。
In the past, directly attached storage systems have implemented minimal security checks because the physical connection offered little chance for attack. Transporting block storage (SCSI) over IP opens a whole new opportunity for a variety of malicious attacks. Attacks can take the active form (identity spoofing, man-in-the-middle) or the passive form (eavesdropping).
在过去，直连存储系统实施了最低限度的安全检查，因为物理连接提供的攻击机会很小。通过IP传输块存储（SCSI）为各种恶意攻击提供了全新的机会。攻击可以采取主动形式（身份欺骗，中间人）或被动形式（窃听）。
The security services required for communications depends on the individual network configurations and environments. Organizations are setting up Virtual Private Networks(VPN), also known as Intranets, that will require one set of security functions for communications within the VPN and possibly many different security functions for communications outside the VPN to support geographically separate components. The iSCSI protocol is applicable to a wide range of internet working environments that may employ different security policies. iSCSI MUST provide for strong authentication when increased security is required. The protocol SHOULD require minimal configuration and overhead in the insecure operation, and allow integration of new security mechanisms without breaking backwards compatible operation.
通信所需的安全服务取决于各个网络配置和环境。各组织正在建立虚拟专用网络（VPN），也称为内部网，这将需要一组用于VPN内通信的安全功能，可能需要许多用于VPN外通信的不同安全功能，以支持地理上独立的组件。iSCSI协议适用于可能采用不同安全策略的各种internet工作环境。当需要提高安全性时，iSCSI必须提供强身份验证。该协议在不安全的操作中应该需要最小的配置和开销，并且允许在不破坏向后兼容操作的情况下集成新的安全机制。
The iSCSI protocol MAY support various levels of authentication security, ranging from no authentication to secure authentication using public or private keys.
iSCSI协议可以支持各种级别的身份验证安全性，从无身份验证到使用公钥或私钥的安全身份验证。
The iSCSI protocol MUST support private authenticated login.
iSCSI协议必须支持私人身份验证登录。
Authenticated login aids the target in blocking the unauthorized use of SCSI resources. "Private" authenticated login mandates protected identity exchange (no clear text passwords at a minimum). Since block storage confidentiality is considered critical in enterprises and many IP networks may have access holes, organizations will want to protect their iSCSI resources.
经过身份验证的登录有助于目标阻止未经授权使用SCSI资源。“私有”身份验证登录要求进行受保护的身份交换（至少没有明文密码）。由于块存储机密性在企业中被认为是至关重要的，而且许多IP网络可能存在访问漏洞，因此企业将希望保护其iSCSI资源。
The iSCSI authenticated login MUST be resilient against attacks since many IP networks are vulnerable to packet inspection.
iSCSI身份验证登录必须具有抵御攻击的能力，因为许多IP网络容易受到数据包检查的攻击。
In addition, the iSCSI protocol MUST support data origin authentication of its communications; data origin authentication MAY be optional to use. Data origin authentication is critical since IP networks are vulnerable to source spoofing, where a malicious third party pretends to send packets from the initiator's IP address. These requirements should be met using standard Internet protocols such as IPsec or TLS. The endpoints may negotiate the authentication method, optionally none.
此外，iSCSI协议必须支持其通信的数据源身份验证；数据源身份验证可能是可选的。数据源身份验证至关重要，因为IP网络容易受到源欺骗的攻击，恶意第三方假装从启动器的IP地址发送数据包。应使用标准的Internet协议（如IPsec或TLS）满足这些要求。端点可以协商身份验证方法，也可以不协商。
The iSCSI protocol SHOULD NOT preclude use of additional data integrity protection protocols (IPSec, TLS).
iSCSI协议不应排除使用其他数据完整性保护协议（IPSec、TLS）。
Block storage is used for storing sensitive information, where data confidentiality is critical. An application may encrypt the data blocks before writing them to storage - this provides the best protection for the application. Even if the storage or communications are compromised, the attacker will have difficulty reading the data.
块存储用于存储敏感信息，其中数据保密性至关重要。应用程序可以在将数据块写入存储器之前对其进行加密—这为应用程序提供了最佳保护。即使存储或通信遭到破坏，攻击者也难以读取数据。
In certain environments, encryption may be desired to provide an extra assurance of confidentiality. An iSCSI implementation MUST provide for the use of a data encryption protocol such as TLS or IPsec ESP to provide data confidentiality between iSCSI endpoints.
在某些环境中，可能需要加密以提供额外的保密性保证。iSCSI实施必须提供数据加密协议（如TLS或IPsec ESP）的使用，以提供iSCSI端点之间的数据机密性。
iSCSI implementations SHOULD be manageable using standard IP-based management protocols. However, the iSCSI protocol document MUST NOT define the management architecture for iSCSI within the network infrastructure. iSCSI will be yet another resource service within a complex environment of network resources (printers, file servers, NAS, application servers, etc). There will certainly be efforts to design how the "block storage service" that iSCSI devices provide is integrated into a comprehensive, shared model, network management
iSCSI实施应使用基于IP的标准管理协议进行管理。但是，iSCSI协议文档不得在网络基础架构中定义iSCSI的管理体系结构。iSCSI将是网络资源（打印机、文件服务器、NAS、应用程序服务器等）复杂环境中的另一种资源服务。我们肯定会努力设计如何将iSCSI设备提供的“块存储服务”集成到一个全面的、共享的网络管理模型中
environment. A "network administrator" (or "storage administrator") will desire to have integrated applications for assigning user names, resource names, etc. and indicating access rights. iSCSI devices presumably will want to interact with these integrated network management applications. The iSCSI protocol document will not attempt to solve that set of problems, or specify means for devices to provide management agents. In fact, there should be no mention of MIBs or any other means of managing iSCSI devices as explicit references in the iSCSI protocol document, because management data and protocols change with the needs of the environment and the business models of the management applications.
环境“网络管理员”（或“存储管理员”）希望拥有用于分配用户名、资源名等并指示访问权限的集成应用程序。iSCSI设备可能希望与这些集成的网络管理应用程序交互。iSCSI协议文档不会试图解决这组问题，也不会指定设备提供管理代理的方法。事实上，在iSCSI协议文档中不应提及MIB或任何其他管理iSCSI设备的方法，因为管理数据和协议会随着环境的需要和管理应用程序的业务模型而变化。
Whenever possible, iSCSI MUST support the naming architecture of SAM-2. Deviations and uncertainties MUST be made explicit, and comments and resolutions worked out between ANSI T10 and the IPS working group.
只要有可能，iSCSI必须支持SAM-2的命名体系结构。必须明确偏差和不确定性，并在ANSI T10和IPS工作组之间制定意见和决议。
The means by which an iSCSI resource is located MUST use or extend existing Internet standard resource location methods. RFC 2348 [12] specifies URL syntax and semantics which should be sufficiently extensible for the iSCSI resource.
iSCSI资源的定位方法必须使用或扩展现有的Internet标准资源定位方法。RFC 2348[12]指定了URL语法和语义，这些语法和语义对于iSCSI资源应该具有足够的可扩展性。
The iSCSI protocol MUST provide a means of identifying an iSCSI storage device by a unique identifier that is independent of the path on which it is found. This name will be used to correlate alternate paths to the same device. The format for the iSCSI names MUST use existing naming authorities, to avoid creating new central administrative tasks. An iSCSI name SHOULD be a human readable string in an international character set encoding.
iSCSI协议必须提供一种通过独立于找到iSCSI存储设备的路径的唯一标识符来识别iSCSI存储设备的方法。此名称将用于将备用路径关联到同一设备。iSCSI名称的格式必须使用现有的命名机构，以避免创建新的中央管理任务。iSCSI名称应为国际字符集编码中的人类可读字符串。
Standard Internet lookup services SHOULD be used to resolve names. For example, Domain Name Services (DNS) MAY be used to resolve the <hostname> portion of a URL to one or multiple IP addresses. When a hostname resolves to multiple addresses, these addresses should be equivalent for functional (possibly not performance) purposes. This means that the addresses can be used interchangeably as long as performance isn't a concern. For example, the same set of SCSI targets MUST be accessible from each of these addresses.
应使用标准Internet查找服务解析名称。例如，域名服务（DNS）可用于将URL的<hostname>部分解析为一个或多个IP地址。当主机名解析为多个地址时，出于功能（可能不是性能）目的，这些地址应该是等效的。这意味着地址可以互换使用，只要性能不是问题。例如，同一组SCSI目标必须可以从每个地址访问。
An iSCSI device naming scheme MUST interact correctly with the proposed SCSI security architecture [99-245r9]. Particular attention must be directed to the proxy naming architecture defined by the new security model. In this new model, a host is identified by an Access ID, and SCSI Logical Unit Numbers (LUNs) can be mapped in a manner that gives each AccessID a unique LU map. Thus, a given LU within a target may be addressed by different LUNs.
iSCSI设备命名方案必须与建议的SCSI安全体系结构正确交互[99-245r9]。必须特别注意新安全模型定义的代理命名体系结构。在这个新模型中，主机由访问ID标识，SCSI逻辑单元号（LUN）的映射方式可以为每个访问ID提供唯一的LU映射。因此，目标中的给定LU可能由不同的LUN寻址。
The iSCSI naming architecture MUST address support of SCSI 3rd party operations such as EXTENDED COPY. The key issue here relates to the naming architecture for SCSI LUs - iSCSI must provide a means of passing a name or handle between parties. iSCSI must specify a means of providing a name or handle that could be used in the XCOPY command and fit within the available space allocated by that command. And it must be possible, of course, for the XCOPY target (the third party) to de-reference the name to the correct target and LU.
iSCSI命名体系结构必须支持SCSI第三方操作，如扩展拷贝。这里的关键问题与SCSI LU的命名体系结构有关—iSCSI必须提供一种在各方之间传递名称或句柄的方法。iSCSI必须指定一种提供名称或句柄的方法，该名称或句柄可以在XCOPY命令中使用，并适合该命令分配的可用空间。当然，XCOPY目标（第三方）必须能够将名称反引用到正确的目标和LU。
iSCSI MUST have no impact on the use of current IP network discovery techniques. Network management platforms discover IP addresses and have various methods of probing the services available through these IP addresses. An iSCSI service should be evident using similar techniques.
iSCSI不得影响当前IP网络发现技术的使用。网络管理平台发现IP地址，并有各种方法通过这些IP地址探测可用的服务。iSCSI服务应该使用类似的技术。
The iSCSI specifications MUST provide some means of determining whether an iSCSI service is available through an IP address. It is expected that iSCSI will be a point of service in a host, just as SNMP, etc are points of services, associated with a well known port number.
iSCSI规范必须提供一些方法来确定iSCSI服务是否可通过IP地址使用。iSCSI将是主机中的服务点，正如SNMP等是与已知端口号关联的服务点一样。
SCSI protocol-dependent techniques SHOULD be used for further discovery beyond the iSCSI layer. Discovery is a complex, multi-layered process. The SCSI protocol specifications provide specific commands for discovering LUs and the commands associated with this process will also work over iSCSI.
SCSI协议相关技术应用于iSCSI层之外的进一步发现。发现是一个复杂的、多层次的过程。SCSI协议规范提供了用于查找LU的特定命令，与此过程相关的命令也将通过iSCSI工作。
The iSCSI protocol MUST provide a method of discovering, given an IP end point on its well-known port, the list of SCSI targets available to the requestor. The use of this discovery service MUST be optional.
iSCSI协议必须提供一种方法，在已知端口上指定IP端点的情况下，发现请求者可用的SCSI目标列表。此发现服务的使用必须是可选的。
Further discovery guidelines are outside the scope of this document and may be addressed in separate Informational documents.
进一步的发现指南不在本文档的范围内，可以在单独的信息文档中进行说明。
As with all services, the denial of service by either incorrect implementations or malicious agents is always a concern. All aspects of the iSCSI protocol SHOULD be scrutinized for potential denial of service issues, and guarded against as much as possible.
与所有服务一样，错误实现或恶意代理的拒绝服务始终是一个令人担忧的问题。应仔细检查iSCSI协议的各个方面是否存在潜在的拒绝服务问题，并尽可能地加以防范。
NATs (Network Address Translator), firewalls, and proxy servers are a reality in today's Internet. These devices present a number of challenges to device access methods being developed for iSCSI. For example, specifying a URL syntax for iSCSI resource connection allows an initiator to address an iSCSI target device both directly and through an iSCSI proxy server or NAT. iSCSI SHOULD allow deployment where functional and optimizing middle-boxes such as firewalls, proxy servers and NATs are present.
NAT（网络地址转换器）、防火墙和代理服务器是当今互联网的现实。这些设备对正在为iSCSI开发的设备访问方法提出了许多挑战。例如，为iSCSI资源连接指定URL语法允许启动器直接或通过iSCSI代理服务器或NAT寻址iSCSI目标设备。iSCSI应允许在防火墙、代理服务器和NAT等具有功能和优化的中间盒的位置进行部署。
The iSCSI protocol's use of IP addressing and TCP port numbers MUST be firewall friendly. This means that all connection requests should normally be addressed to a specific, well-known TCP port. That way, firewalls can filter based on source and destination IP addresses, and destination (target) port number. Additional TCP connections would require different source port numbers (for uniqueness), but could be opened after a security dialogue on the control channel.
iSCSI协议对IP地址和TCP端口号的使用必须对防火墙友好。这意味着所有的连接请求通常都应该发送到一个特定的、众所周知的TCP端口。这样，防火墙可以根据源和目标IP地址以及目标（目标）端口号进行过滤。额外的TCP连接需要不同的源端口号（为了唯一性），但可以在控制通道上的安全对话后打开。
It's important that iSCSI operate through a firewall to provide a possible means of defending against Denial of Service (DoS) assaults from less-trusted areas of the network. It is assumed that a firewall will have much greater processing power for dismissing bogus connection requests than end nodes.
iSCSI必须通过防火墙进行操作，以提供一种可能的方法来抵御来自网络中不太可信区域的拒绝服务（DoS）攻击。假设防火墙在拒绝虚假连接请求方面比终端节点具有更大的处理能力。
The iSCSI protocol MUST be a good network citizen with proven congestion control (as defined in [RFC2914]). In addition, iSCSI implementations MUST NOT use multiple connections as a means to avoid transport-layer congestion control.
iSCSI协议必须是经过验证的拥塞控制良好的网络公民（如[RFC2914]中所定义）。此外，iSCSI实施不得使用多个连接作为避免传输层拥塞控制的手段。
Certain definitions are offered here, with references to the original document where applicable, in order to clarify the discussion of requirements. Definitions without references are the work of the authors and reviewers of this document.
此处提供了某些定义，并在适用时参考了原始文件，以澄清对需求的讨论。无参考文献的定义是本文件的作者和评审人员的工作。
Logical Unit (LU): A target-resident entity that implements a device model and executes SCSI commands sent by an application client [SAM-2, sec. 3.1.50, p. 7].
逻辑单元（LU）：实现设备模型并执行应用程序客户端发送的SCSI命令的目标驻留实体[SAM-2，第3.1.50节，第7页]。
Logical Unit Number (LUN): A 64-bit identifier for a logical unit [SAM-2, sec. 3.1.52, p. 7].
逻辑单元号（LUN）：逻辑单元的64位标识符[SAM-2，第3.1.52节，第7页]。
SCSI Device: A device that is connected to a service delivery subsystem and supports a SCSI application protocol [SAM-2, sec. 3.1.78, p. 9].
SCSI设备：连接到服务交付子系统并支持SCSI应用程序协议的设备[SAM-2，第3.1.78节，第9页]。
Service Delivery Port (SDP): A device-resident interface used by the application client, device server, or task manager to enter and retrieve requests and responses from the service delivery subsystem. Synonymous with port (SAM-2 sec. 3.1.61) [SAM-2, sec. 3.1.89, p. 9].
服务交付端口（SDP）：应用程序客户端、设备服务器或任务管理器用于输入和检索来自服务交付子系统的请求和响应的设备驻留接口。与端口同义（SAM-2第3.1.61节）[SAM-2第3.1.89节，第9页]。
Target: A SCSI device that receives a SCSI command and directs it to one or more logical units for execution [SAM-2 sec. 3.1.97, p. 10].
目标：接收SCSI命令并将其定向到一个或多个逻辑单元执行的SCSI设备[SAM-2第3.1.97节，第10页]。
Task: An object within the logical unit representing the work associated with a command or a group of linked commands [SAM-2, sec. 3.1.98, p. 10].
任务：逻辑单元内的一个对象，表示与一个命令或一组链接命令相关联的工作[SAM-2，第3.1.98节，第10页]。
Transaction: A cooperative interaction between two objects, involving the exchange of information or the execution of some service by one object on behalf of the other [SAM-2, sec. 3.1.109, p. 10].
事务：两个对象之间的协作交互，涉及一个对象代表另一个对象交换信息或执行某些服务[SAM-2，第3.1.109节，第10页]。
1. Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996.
1. Bradner，S.，“互联网标准过程——第3版”，BCP 9，RFC 2026，1996年10月。
2. Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
2. Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
3. [SAM-2] ANSI NCITS. Weber, Ralph O., editor. SCSI Architecture Model -2 (SAM-2). T10 Project 1157-D. rev 23, 16 Mar 2002.
3. [SAM-2]ANSI NCITS。韦伯，拉尔夫·O.，编辑。SCSI体系结构模型-2（SAM-2）。T10项目1157-D，版本23，2002年3月16日。
4. [SPC-2] ANSI NCITS. Weber, Ralph O., editor. SCSI Primary Commands 2 (SPC-2). T10 Project 1236-D. rev 20, 18 July 2001.
4. [SPC-2]ANSI NCITS。韦伯，拉尔夫·O.，编辑。SCSI主命令2（SPC-2）。T10项目1236-D，版本20，2001年7月18日。
5. [CAM-3] ANSI NCITS. Dallas, William D., editor. Information Technology - Common Access Method - 3 (CAM-3)). X3T10 Project 990D. rev 3, 16 Mar 1998.
5. [CAM-3]ANSI NCITS。达拉斯，威廉·D.，编辑。信息技术.公共访问方法.3（CAM-3））。X3T10项目990D。1998年3月16日第3次修订。
6. [99-245r8] Hafner, Jim. A Detailed Proposal for Access Controls. T10/99-245 revision 9, 26 Apr 2000.
6. [99-245r8]哈夫纳，吉姆。访问控制的详细建议。T10/99-245第9版，2000年4月26日。
7. [SPI-X] ANSI NCITS. SCSI Parallel Interface - X.
7. [SPI-X]ANSI NCITS。SCSI并行接口-X。
8. [FCP] ANSI NCITS. SCSI-3 Fibre Channel Protocol [ANSI X3.269:1996].
8. [FCP]ANSI NCITS。SCSI-3光纤通道协议[ANSI X3.269:1996]。
9. [FCP-2] ANSI NCITS. SCSI-3 Fibre Channel Protocol - 2 [T10/1144-D].
9. [FCP-2]ANSI NCITS。SCSI-3光纤通道协议-2[T10/1144-D]。
10. Paxon, V. End-to-end internet packet dynamics, IEEE Transactions on Networking 7,3 (June 1999) pg 277-292.
10. Paxon，V.《端到端互联网数据包动力学》，IEEE网络交易7,3（1999年6月）第277-292页。
11. Stone J., Partridge, C. When the CRC and TCP checksum disagree, ACM Sigcomm (Sept. 2000).
11. Stone J.，Partridge，C.当CRC和TCP校验和不一致时，ACM Sigcomm（2000年9月）。
12. Malkin, G. and A. Harkin, "TFTP Blocksize Option", RFC 2348, May 1998.
12. Malkin，G.和A.Harkin，“TFTP块大小选项”，RFC 2348，1998年5月。
13. Floyd, S., "Congestion Control Principles", BCP 14, RFC 2914, September 2000.
13. Floyd，S.，“拥塞控制原则”，BCP 14，RFC 2914，2000年9月。
Special thanks to Julian Satran, IBM and David Black, EMC for their extensive review comments.
特别感谢IBM的Julian Satran和EMC的David Black提供了广泛的评论意见。
Address comments to:
提出意见：
Marjorie Krueger Hewlett-Packard Corporation 8000 Foothills Blvd Roseville, CA 95747-5668, USA Phone: +1 916 785-2656 EMail: marjorie_krueger@hp.com
Marjorie Krueger Hewlett-Packard Corporation 8000 Foothills Blvd Roseville，CA 95747-5668，美国电话：+1 916 785-2656电子邮件：Marjorie_krueger@hp.com
Randy Haagens Hewlett-Packard Corporation 8000 Foothills Blvd Roseville, CA 95747-5668, USA Phone: +1 916 785-4578 EMail: Randy_Haagens@hp.com
Randy Haagens Hewlett-Packard Corporation 8000 Foothills Blvd Roseville，CA 95747-5668，美国电话：+1 916 785-4578电子邮件：Randy_Haagens@hp.com
Costa Sapuntzakis Stanford University 353 Serra Mall Dr #407 Stanford, CA 94305 Phone: 650-723-2458 EMail: csapuntz@stanford.edu
Costa Sapuntzakis斯坦福大学353 Serra Mall Dr#407 Stanford，CA 94305电话：650-723-2458电子邮件：csapuntz@stanford.edu
Mark Bakke Cisco Systems, Inc. 6450 Wedgwood Road Maple Grove, MN 55311 Phone: +1 763 398-1054 EMail: mbakke@cisco.com
Mark Bakke Cisco Systems，Inc.明尼苏达州枫树林韦奇伍德路6450号55311电话：+1 763 398-1054电子邮件：mbakke@cisco.com
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Acknowledgement
确认
Funding for the RFC Editor function is currently provided by the Internet Society.
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