1. A Reset on Softwire Mesh Multicast Mingwei Xu Yong Cui CERNET, China Chris Metz, Cisco IETF76 Meeting, Hiroshima Nov 2009

2. Why? RFC4925 and Softwires Charter state multicast is a requirement Operators have expressed requirements for multicast solution Softwire Mesh Unicast methods defined. Where is the Multicast? – Is section 11 of RFC5565 sufficient? Imminent IPv4 run-out; need to complete Softwires Mesh functions (include multicast)

3. Softwire Mesh Multicast I-IP Backbone E-IP AFBR E-IP AFBR E-IP S R R I-IP Tree E-IP Tree

4. Softwire Mesh Multicast Framework 1:1 Mapping (Internet Multicast Model) – one E-IP tree maps to one I-IP tree – I-IP core multicast state scales linearly with E-IP client multicast state “mVPN-like” – I-IP core multicast state scales less than linearly with E-IP client multicast state – AFBR routers act like PE routers supporting one VPN – Techniques outlined in L3VPN Multicast docs

5. Use-Cases and Methods NumberE-IPI-IPMappingMethodsComments 1. IPv6IPv4 (and MPLS) 1:1 PIM RPF Vector Inter-AFBR signaling (PIM or BGP) Need details 2. IPv4IPv61:1 Algorithmic IPv4- to-IPv6 mapping at AFBR Need details 3. IPv6IPv4 (and MPLS) N:1 Employ L3VPN multicast techniques mVPNv6 implementations exist 4. IPv4IPv6N:1 Employ L3VPN multicast techniques Lower priority

6. Summary and Suggested Next Steps There is unfinished work – Softwire Mesh Multicast Suggested Next Steps – Focus on 1:1 Use-Cases – Document these use-cases and add more details on protocol and vehicle functions and behaviors