2.8.7 IP Storage (ips)

Last Modified: 2004-06-07

Chair(s):

Transport Area Director(s):

Transport Area Advisor:

Technical Advisor(s):

Mailing Lists:

Description of Working Group:

The protocols to be encapsulated expect a reliable transport, in that failure to deliver data is considered to be a rare event for which time-consuming recovery at higher levels is acceptable. This has implications for both the choice of transport protocols and design of the encapsulation(s). The WG's encapsulations may require quality of service assurances (e.g., bounded latency) to operate successfully; the WG will consider what assurances are appropriate and how to provide them in shared traffic environments (e.g., the Internet) based on existing IETF QoS mechanisms such as Differentiated Services.

Use of IP-based transports raises issues that do not occur in the existing transports for the protocols to be encapsulated. The WG's protocol encapsulations will incorporate the following:

- Congestion control suitable for shared traffic network environments such as the Internet.

- Security including authentication, keyed cryptographic data integrity and confidentiality, sufficient to defend against threats up to and including those that can be expected on a public network. Implementation of basic security functionality will be required, although usage may be optional.

The WG will also address the following issues related to its protocol encapsulations:

- Naming and discovery mechanisms for the encapsulated protocols on IP-based networks, including both discovery of resources (e.g., storage) for access by the discovering entity, and discovery for management.

- Management, including appropriate MIB definition(s) for the encapsulations.

- By agreement with the IESG, the WG will additionally develop MIB definitions for the SCSI and Fiber Channel standards.

The WG specifications will allow the implementation of bridges and gateways that connect to existing implementations of the encapsulated protocols. The WG will preserve the approaches to discovery, multi-pathing, booting, and similar issues taken by the protocols it encapsulates to the extent feasible.

It may be necessary for traffic using the WG's encapsulations to pass through Network Address Translators (NATs) and/or firewalls in some circumstances; the WG will endeavor to design NAT- and firewall-friendly protocols that do not dynamically select target ports or require Application Level Gateways.

Effective implementations of some IP transports for the encapsulated protocols are likely to require hardware acceleration; the WG will consider issues concerning the effective implementation of its protocols in hardware.

The standard internet checksum is weaker than the checksums use by other implementations of the protocols to be encapsulated. The WG will consider what levels of data integrity assurance are required and how they should be achieved.

The WG will produce requirements and specification documents for each protocol encapsulation, and may produce applicability statements. The requirements and specification documents will consider both disk and tape devices, taking note of the variation in scale from single drives to large disk arrays and tape libraries, although the requirements and specifications need not encompass all such devices.

The WG will not work on:

- Extensions to existing protocols such as SCSI and Fibre Channel beyond those strictly necessary for the use of IP-based transports.

- Modifications to internet transport protocols or approaches requiring transport protocol options that are not widely supported, although the WG may recommend use of such options for block storage traffic.

- Support for environments in which significant data loss or data corruption is acceptable.

- File system protocols.

Operational Structure:

Keith McCloghrie (kzm@cisco.com) will serve as the MIB and Network Management advisor for the WG.

Due to the scope of the task and the need for parallel progress on multiple work items, the WG effort is organized as follows:

A technical coordinator will be identified and selected for each protocol encapsulation adopted as a work item by the group. This person will be responsible for coordinating the technical efforts of the group with respect to that encapsulation, working with and motivating the document editors, and evangelizing the group's work within both the community and relevant external organizations such as T10 and T11.

In addition to the normal responsibilities of IETF working group chairs, the IPS chairs are responsible for selection of coordinators, identifying areas of technical commonality and building cross-technology efforts within the group.

Coordinators for initially important encapsulations:

SCSI over IP (aka iSCSI): John Hufferd (hufferd@us.ibm.com)

Fibre Channel (FC-2) over IP: Murali Rajagopal (muralir@cox.net)

iFCP: Franco Travostino (travos@nortelnetworks.com)

Goals and Milestones:

Internet-Drafts:

Request For Comments:

• Presentation 0

• Presentation 1

• Presentation 2

• Presentation 3