IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 1/29

IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 2/29 Alain Durand Staff Engineer Sun Microsystems, Inc. Co-chair of the IETF NGtrans working group IPv6 transition strategies

IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 3/29 Outline  History  Why is it a difficult problem?  Approach  NGtrans story  Tools  Case study

IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 4/29 History  Previous Internet transition: 1983 –Transition from NCP to TCP happened overnight. It was a nightmare... –There was only few hundred hosts at the time...  Lessons learned: –There would be no D day in IPv4 to IPv6 transition. –Some transition mechanisms MUST be defined to allow IPv4 and IPv6 hosts to talk to each other.

IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 5/29 Why is it a difficult problem?  IPv4 is a huge success story: 150 millions + hosts  IPv6 "had" a chicken and egg problem.  Early IPv6 adopters face Meltcafe law: –"The value of a network is proportional to the square of the number of users."  We are still very early in the transition. –We are talking about a 10 year process…

IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 6/29 Approach  Strategies –From the core out… –From the edges in…  Constraints –Do not disrupt IPv4 traffic –Incremental deployment  Solutions –Not one tool, but a toolbox

IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 7/29 NGtrans story Part 1: the network  Use IPv6 in IPv4 tunnels. –Use the Internet as a media.  Use IPv6 over any layer 2 links. –It is just another layer3 protocol. –Reuse the physical infrastructure.

IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 8/29 NGtrans story Part 2: the stacks  "Hosts" & "Routers" will get hybrid stacks. –The IPv4 part will not necessarily be configured. –Tunnels will be used to bypass IPv4 only routers.  Those stacks may come as software upgrades. –Some hardware change may be necessary.  New “device” may choose to implement an IPv6-only stack. –e.g.: cellular phones.

IPv6 transition strategies IPv6 forum OSAKA 12/19/2000 9/29 NGtrans story Part 3: the applications  IPv6 ready applications are needed.  Some sort of interoperability is needed in between IPv4 and IPv6. –Interoperability has a cost. 100% interoperability is not always necessary/possible. Network architect would pick the right tool to achieve the desired level of interoperability.

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Basic mechanism: Hybrid stack (a.k.a. dual stack)  A node can "talk" IPv4 & IPv6.  New applications support both IPv4 & IPv6. –No need for two set of applications, one for v4, one for v6. IPv4 IPv6 TCP/UDP Application LAN

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Basic mechanism: Tunnel  IPv6 packets are "encapsulated" within IPv4 packets. IPv4IPv6 TCP/UDP Payload

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Network tools  Automatic tunnels –Very little usage.  6over4 –Interesting within an IPv4 multicast site.  Configured tunnels –Widely deployed in the 6bone. –Require manual configuration.  Tunnel Broker  6to4

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Connecting two IPv6 clouds: Configured tunnel IPv6 IPv4 hybrid stack routers tunnel

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Connecting an isolated host: Tunnel Broker/1 IPv6 Internet IPv4 Internet isolated hybrid stack host tunnel broker tunnel request

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Tunnel Broker/2 tunnel server tunnel config tunnel config IPv6 Internet IPv4 Internet isolated hybrid stack host tunnel broker

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Tunnel Broker/3 tunnel IPv6 Internet IPv4 Internet isolated hybrid stack host tunnel server

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 6to4 mechanism One IPv4 global address => one /48 IPv6 site prefix 2001IPv4 SLAInterface ID 48 bits 16 bits 64 bits ISPv4 assignedmanagedauto-configuredpre-defined Stateless tunnels span over the IPv4 infrastructure without configuration to reach other 6to4 domains.

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Building automatic extranets: Connecting IPv6 clouds with 6to4 6to4 hybrid- stack routers IPv6 IPv4 tunnels 6to4

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Other tools IP level SIIT NAT-PT TCP level TCP-relays SOCKS Application level Bump in the API Proxies DSTM ( Dual Stack Transition Mechanism) Translator Non translator

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 0 IPv4 site Private address space NFS pop client IPv4 Internet Exit router NATv4 ALGs client routers web v4 IPv4 only host IPv4 only router IPv4 only network proxy IPv4 site web

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 1 hybrid stack servers & routers v4/v6 site NFS web client IPv4 Internet Exit router NATv4 ALGs client v4/v6 routers v4 routers v4 v4/v6 pop Hybrid v4/v6 host Hybrid v6/v6 router Hybrid v4/v6 network proxy web

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 2 hybrid stack clients v4/v6 site NFS client IPv4 Internet Exit router NATv4 ALGs client v4/v6 routers v4 router v4/v6 v4 v4/v6 client web pop proxy web

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 3 6to4 connection IPv4 Internet Exit router NATv4 6to4 router ALGs Other 6to4 sites 6to4 tunnels v4/v6 site NFS client v4/v6 routers v4 router v4/v6 v4 v4/v6 client web pop proxy web IPv6 tunnel over IPv4

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 3bis Building extranets IPv4 Internet Exit routers NATv4 ALGs 6to4 router 6to4 tunnel v4/v6 site A NFS client v4/v6 routers v4 router v4/v6 v4 v4/v6 client web pop proxy v4/v6 site B NFS client v4/v6 routers v4 router v4/v6 v4 v4/v6 client web pop proxy

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 4 IPv6 only hosts IPv4 Internet Exit router NATv4 ALGs 6to4 router 6to4 tunnels IPv6 only host IPv6 only router Other 6to4 sites IPv6 only network v4/v6 site NFS client v4/v6 routers v6 only router v4/v6 v6 v4/v6 client web pop proxy web

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 5 IPv6 only hosts to IPv4 servers v4/v6 site printer IPv4 Internet Exit router NATv4 v4/v6 ALGs 6to4 router client v4 router v6 router v6 v4 proxy v4/v6 router v4/v6 6to4 tunnels Other 6to4 sites web print server

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 6 Native IPv6 connection IPv4 Internet Exit v4/v6 router NATv4 v4/v6 ALGs 6to4 router 6to4 tunnels Other 6to4 sites web IPv6 Site IPv6 ISPs v4/v6 site NFS client v4/v6 routers v6 only router v4/v6 v6 v4/v6 client web pop proxy

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 Case study: phase 99 IPv6 site / IPv6 Internet IPv6 site NFS client IPv6 Internet Exit router to IPv6 ISP client v6 routers v6 routers v6 client IPv4 Interne t web pop NAT-PT or proxies

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29 References  g   

IPv6 transition strategies IPv6 forum OSAKA 12/19/ /29