IETF 80 th Lightweight Address Family Transition for IPv6 draft-sunq-v6ops-laft6-01 Chongfeng Xie( China Telecom ) Qiong Sun( China Telecom)

IETF 80 th Existing Solution Overview Stateful  Keep per-session state in CGN: scalability problem  Dynamic state is hard for load balancing and traffic logging  No address restriction  Little impact on existing addressing and routing Stateless  No state, good scalability  Easy for load balancing and traffic logging  Have some restriction on addressing  Need to take modification on existing addressing and routing system

IETF 80 th Deployment Guidelines Better tradeoff operational guideline: – Better scalability Keep state as few as possible in core network Stable state is good for logging, traffic engineering, etc. – Flexible addressing Little modification to existing addressing and routing system Define flexible addressing plan for different purpose Should we need a solution with less state and less address format restriction ?

IETF 80 th LAFT6 Overview LAFT6: Lightweight address family transition for IPv6 Lightweight: – State-management: CPE-based state, rather than session base, say 100( CPEs )×1000( sessions ) states in ds-lite  100( CPEs ) in LAFT6 – Addressing: No IPv6 address-format restriction to support easy deployment – Routing: No extra impact on existing routing infrastructure – Logging: Reduces logging information can be achieved – State Synchronization: Relatively more stable state with for HA support. – Little impact on existing infrastructure: it can support rapid deployment in operational network.

IETF 80 th Broadband Deployment scenarios IPv4 server Access Network (IPv6) Metro Network (IPv6) Backbone (IPv4) Backbone (IPv6) IPv6 server BR BRAS/SR LAFT6- NGW LAFT6- CGW Dual-stack user IPv6-only user In the further home network, there might be IPv4/IPv6 terminals behind one CPE.

IETF 80 th LAFT6 solution overview LAFT6 is a general lightweight address sharing framework which has the features of lightweight state-management and lightweight addressing. How to achieve address sharing ? IPv4 Address sharing +Port allocation How to achieve Lightweight ? Distributed state + Port aggregation How to achieve IPv6 Transition ? Mixed utilization of tunnel & translation

IETF 80 th Port range pr3 LAFT6 solution overview Port Range pr1 Port range pr2 LAFT-CGWLAFT-NGW [v6_addr1 ： v4_add1, pr1] [v6_addr2 ： v4_add1, pr2] [v6_addr3 ： v4_add2, pr3] End user 1 End user 2 End user 3 IPv4 shared address v4_add1 v4_add2 v6_add1 v6_add2 v6_add3 Lightweight state management CPE-based state v4_priv1 v4_priv2 v4_priv3 Lightweight addressing： No restriction to IPv6 address format No plan for private IPv4 address

IETF 80 th LAFT6 workflow IPv4  IPv4 IPv6  IPv4

IETF 80 th LAFT-CGW Initialization Building extended binding table – TCP and UDP – ICMP query Packet translation Encapsulation Fragmentation and reassembly DNS proxy (X',x) (T,y) (X',i1) (T,i2)

IETF 80 th LAFT-NGW Port-range management / Port-range Binding Table Encapsulation Fragmentation and reassembly (X') (T,pr)

IETF 80 th Deployment consideration Addressing and Routing – No impact on existing IPv6 address allocation system – No impact on routing system DNS – LAFT-CGW implement IPv4-to-IPv6 DNS proxy / DNS64 – No impact on existing DNS server AAA and User Management – In the initial phase of deployment, the maximum number of port number for subscribers can be configured uniformly – Differentiated service can be offered with different maximum number of port number in the future.

IETF 80 th Deployment consideration Traffic logging – Only per-subscriber log entries need to be recorded Deployment in Large SP Network – "centralized model" and "distributed model". ALG considerations – no ALG in carrier side network – User controlled ALG in customer side CPE issue – NAT is a common function in existing CPE – Only need to add tunnel/translation function for different scenarios

IETF 80 th LAFT6 test in operational network Application test: Web, , Instant Message, ftp, telnet, SSH, video, Video Camera, P2P, online game, Voip, VPN etc Operating System test: Win7, VISTA, windows XP. Performance test: concurrent session number, throughput.

IETF 80 th Summary LAFT6 has good scalability – LAFT-NGW is a lightweight solution which only maintains per-subscriber state information. It can easily support a large amount of concurrent subscribers. LAFT6 can be deployed rapidly – There is no modification to existing addressing and routing system in our operational network. And it is simple to achieve traffic tracing and logging. LAFT6 can support a majority of current IPv4 applications and a variety of Operating Systems.

IETF 80 th Next Steps Comments and contributions are welcome – draft-sunq-v6ops-laft6-01

IETF 80 th Thank You!