Softwire wg Alain Durand, Comcast David Ward, Cisco

Note Well Any submission to the IETF intended by the Contributor for publication as all or part of an IETF Internet-Draft or RFC and any statement made within the context of an IETF activity is considered an "IETF Contribution". Such statements include oral statements in IETF sessions, as well as written and electronic communications made at any time or place, which are addressed to: the IETF plenary session, any IETF working group or portion thereof, the IESG, or any member thereof on behalf of the IESG, the IAB or any member thereof on behalf of the IAB, any IETF mailing list, including the IETF list itself, any working group or design team list, or any other list functioning under IETF auspices, the RFC Editor or the Internet-Drafts function All IETF Contributions are subject to the rules of RFC 3978 and RFC Statements made outside of an IETF session, mailing list or other function, that are clearly not intended to be input to an IETF activity, group or function, are not IETF Contributions in the context of this notice.RFC 3978RFC 3979 Please consult RFC 3978 for details.RFC 3978

Wg status Charter went to internal & external review Comments received Chairs, AD & IESG members started addressing the comments… …AD had a baby! (Congratulation!) As of this morning, we are approved as a wg by the IESG! –Secretariat still needs to make it formal

Agenda Overview of meeting in Paris (Chairs) Hub and Spoke Problem Overview (Durand) –Hub and Spoke Illustration (Miyakawa, Palet, Williams) Mesh Problem Overview (Ward) –Mesh Illustration (Li) Status of draft problem statement (Chairs) Next steps (Chairs, all)

Paris Interim Meeting We held an interim meeting in Paris on October 11 th -12 th –18 participants, intense discussions, very productive meeting Focus on problem statement –draft-durand-softwire-problem-statement-00.txt edited in rush just before the cut-off date (excuse typos…) 2 problems identified, topology driven: –Access network, customer initiated, one exit path [Hubs & Spokes] –Core network, ISP initiated, complex routing topology [Mesh] We will look at both problems independently –Hopefully, they will share enough common technology

Hub & Spoke Description

Hubs & Spokes Problem Description: –Access network problem, customer initiated, one exit path Applicability: –ISPs with Dual Stack core and a number of dual stack Points of Presence (“Hubs”) where they connect their customers. 3 usage cases have been identified: –the networks between the CPE router and the hub supports only one address family. –the CPE router cannot be easily upgraded to support both address families, a softwire is created from a node behind the CPE router –Same, but initiated from another router behind the CPE router

Usage Case 1 Dual AF Single AF CPE Router Dual AF Softwire Initiator Softwire Concentrator

Usage Case 2 Dual AF CPE Router Single AF Dual AF Host Softwire Initiator Softwire Concentrator

Usage Case 3 Dual AF CPE Router Single AF Dual AF Router Softwire Initiator Softwire Concentrator

Hubs & Spokes Assumptions NAT/PAT (in IPv4) is present Not always upgradeable CPE router “Stable” IPv6 prefix desired Softwires initiated by customer –Customer side: softwire initiator May be a host or a router –ISP side: softwire concentrator Routing: –default route from softwire initiator to concentrator (CPE routers do not generally run a routing protocol, but the softwire solution will work even if it does.)

Hubs & Spokes Properties (1) Scaling: –to the millions of softwire customers Set-up time (a.k.a. “latency”) –A fraction of the total set-up time of the CPE router Multicast –Classic multicast solution run over the softwire

Hubs & Spokes Properties (2) Security –Must support secure user authentication May be turned off. –Must be able to support payload security when desired outside of the softwire mechanism Operation And Management –Keep alive –Usage accounting –End point failure detection (inner address of the softwire) –Path failure detection (outer address of the softwire)

Hubs & Spokes Encapsulations Critical path –IPv6/IPv4 –IPv6/UDP/IPv4 –IPv4/IPv6 Other encapsulations to be supported later (e.g. IPv6/IPv6)

Hub & Spoke Illustrations Slides from Shin, Carl & Jordi

Mesh Description

Mesh Problem Description: –Core network problem, ISP initiated, complex routing topology Applicability : –ISPs (or large enterprise networks acting as ISP for their internal resources) establish connectivity to 'islands' of networks of one address family type across a transit core of a differing address family type.

Mesh Diagram IPv6-only Transit Core BGP Dual-Stack AFBR IPv4 Access Island IPv4 Access Island IPv4 Access Island IPv4 Access Island IPv6 Access Network IPv6 Access Network

AFBR To provide reachability across the transit core dual-stack devices are installed that act as "Address Family Boundary Routers”. –Creates a limited dual-stack edge network –Core can be solely one AF and islands don’t require upgrade AFBR provide peering across AS or within an AS Can be used inconjunction w/ route reflectors

Full Mesh Overlay for Many2Many connnectivity AFBR V6 transit V4 island

May have different encaps available Must have solution to allow for negotiation and preference of encap AFBR MGRE IPsec V6 transit core AFBR MGRE,L2TPv3 AFBR L2TPv3 MPLS V4 island L2TPv3 MGRE IPsec

Must support Applications…. L3-VPN using 2547bis Route Reflector AFBR V6 transit V4 island AFBR VPN

Mesh properties (1) Scaling –Number of AFBR related to the number of islands and exit points from islands (x0-x00 islands) We know of no cases of x islands –Full routing table needs to be supported Islands can carry x00000 of routes Services / Encapsulation –v4/v6 or v6/v4 –L2VPN –L3VPN (overlapping address spaces) –Multicast a must in all cases Security –No “user” authentication –Authentication for control plane may be turned off –Support for IPsec in data plane (outside of softwires)

Mesh properties (2) Operation And Management –No need for keepalive –Usage accounting –End point failure detection –Path failure detection –Flexible encapsulation possibilities –Interconnection at L2 or L3 –Cannot require full mesh of all AFBRs under all circumstances

Mesh Illustrations Slides from Pr Li

Problem Statement Draft Status Problem statement described in draft-durand-softwire-problem-statement-00.txt Comments received on the ML –Typos –Some minor stuff –n engineer that comes up with n+1 design syndrome –3 issues raised about the Mesh problem: Scale –Presented today Should this be solved at layer 2 or layer 3 –Crystal ball says both (This belongs to the solution space) Should the softwires be initiated from the PE or CPE or both? –Crystal ball says most commonly PE (for mesh)

Next Steps Mark finish the creation of the wg! –Done, minor nits on charter + secretariat action Rev problem statement draft –draft-ietf-softwire-problem-statement-00.txt Nov. 14th –draft-ietf-softwire-problem-statement-01.txt Dec. 1 st WG Last Call on problem statement draft –Target: Dec. 8 th Interim meeting on solution space (Jan/Feb 06) –Last was in Europe, Hong Kong?