Considerations for Stateless Translation (IVI/dIVI) in Large SP draft-sunq-v6ops-ivi-sp- 01

1. Considerations for Stateless Translation (IVI/dIVI) in Large SPdraft-sunq-v6ops-ivi-sp-01 Qiong Sun(China Telecom) Heyu Wang(China Telecom) Xing Li(Tsinghua University) Congxiao Bao(Tsinghua University) Ming Feng(China Telecom)

2. IPv6 Transition Overview • IPv6 deployment is a huge systematic project and there is no single solution which can solve all the problems. • We mainly focus on IVI/dIVI in this document and explore the way to deploy it in SP network. Translation: IVI/dIVI, NAT64, DNS64, FTP64, etc. Tunneling: DS-Lite/GI-DS-Lite, A+P, SAM, etc. Dual-Stack: NAT444, CGN

3. Major Requirements for IPv6 transition • The pool of public IPv4 addressing is nearing its exhaustion. • Basic requirements in IPv6 transition • Reduce IPv4 address consumption • Accelerate the deployment of IPv6 • No perceived degradation of customer experience • Achieve scalability, simplicity and high availability • Operational requirements in IPv6 transition • Incremental deployment • Integrated address assignment and user authentication • User management and network management • Traceability for the origin of IPv6 traffic

4. Features of dIVI • dIVI is an extension of stateless translation (IVI), which enables • Sharing public IPv4 addresses among several IPv6 end systems • Support bidirectional initiated communications • No requirements for ALG • No requirements for DNS64 The figure is from proceedings of ietf76

5. Laboratory Experiment IPv4 Internet R1 1:N IVI Hgw 1.0 H 1.0 R3 IPv6 network R5 DNS H 1.1 S Hgw 1.1 R4 H 1.2 Hgw 1.2 IPv6 Internet R2 • IVI6= XXXX:XXXX:XXXX::/48 IPv6/48 • IVI4= XXX.XXX.XXX.XXX/30 IPv4/24 • Ratio= 128(512 available ports per user) • Host Non-IVI6= YYYY:YYYY:YYYY::/48 IPv6/48

6. Experimental Results • From the experiment, we can have the following conclusions: • dIVI can have good scalabilityand it can be deployed in an incremental way • dIVI can support a majority of current IPv4 applications • dIVI can support a variety of Operating Systems • Port restriction will not have evident impact on user experience with reasonable port configuration.

7. dIVI Deployment Scenarios in SP(1) CR IPv4-only user Backbone (IPv4) 1:N IVI Hgw 1.0 BRAS/SR Metro Network (IPv6) Access Network (IPv6) CR IPv4 Server IPv6 traffic IPv4 traffic

8. dIVI Deployment Scenarios in SP(2) IPv4 Server CR Backbone (IPv4) 1:N IVI BRAS/SR Metro Network (IPv6) Access Network (IPv6) CR Hgw 2.0 Backbone (IPv6) Dual-stack user IPv6 traffic IPv6 Server IPv4 traffic

9. Deployment Considerations • Basic configurationin commercial SP network • Addressing • IPv6 address: No need to allocate IVI6 address explicitly. • IPv4 address: Hgw needs to get IVI4 address and reallocate it to end user. • Routing • IVI4(i) and IVI6(i) will be aggregated to ISP’s IPv4 and ISP’s IPv6 address. • IVI6(i): Hgw 1:N IVI Xlate IVI4(i): 1:N IVI Xlate  Internet • Automatic announcement via dynamic routing protocols • DNS • No DNS64/DNS46 needed in dIVI. • Implement IPv4-to-IPv6 DNS Proxy

10. Deployment Considerations • Operational considerationsin commercial SP network • AAA and User Management • support the identification of IPv6-only/dIVI subscriber in AAA • Network management • Manage IPv6-only network, including IPv6 MIB modules, Netflow, etc. • Manage the translation process, including dIVI device management, dIVI traffic monitoring, etc. • CPE Requirements and Configuration • Address assignment: support IVI4 address assignment • Integrated user authentication function • DNS configuration: support IPv4-to-IPv6 DNS proxy

11. Deployment Considerations • Operational considerations in commercial SP network • dIVI Xlate Placement • Centralized Model • It can be deployed in the place of Core Router, or in the entrance of ICP. • It can reduce cost, be easier for management, fit for stateless solution. • Distributed model • It can be integrated with BRAS/SR. • MAN has to support dual-stack, and so decreased operational cost is rather limited. • ALG consideration • dIVI does not require ALG.

12. Conclusion • dIVI is one of the IPv6 transition solutions which can meet the majority of IPv6 transition requirements. • In order to deploy transition techniques in commercial network, special attention should be paid to operational issues in SP network. • Most of the operational issues are not specific to dIVI, but rather to a general requirement on all IPv6 transition techniques. • We highly recommend that manufactures should take the corresponding extensions for IPv6 transition.

13. Next Steps • Take further trial in commercial network • Comments and contributions are welcome • http://tools.ietf.org/html/draft-sunq-v6ops-ivi-sp-01

14. Thank You!

15. dIVI References • dIVI is an extension of stateless translation (IVI) • https://datatracker.ietf.org/doc/rfc6052/ • https://datatracker.ietf.org/doc/draft-ietf-behave-v6v4-xlate/ • https://datatracker.ietf.org/doc/draft-bcx-address-fmt-extension/ • dIVI references can be found in • http://tools.ietf.org/html/draft-xli-behave-divi-01 • http://www.ietf.org/proceedings/76/slides/behave-10.pdf