Hi, Sri, Inline please
2009/12/1 Sri Gundavelli <[email protected]>: > Hi Hui: > > > > On Sun, 29 Nov 2009, Hui Deng wrote: > >> Dear Alain and Sri, >> >> Please allow me try to summarize the discussion about v4-v4 communication >> within the same sub-network. >> > > Please see below. > > >> >> GW-Init-DS-Lite >> Several thing not yet clear, it depends on what kind of PDP (v6/v4v6)? >> > > I dont see response to my specific questions in this email. Excuse me, I am swamped, > > Not sure, what scenario you are refering to. Overlapping or > non-overlapping ? I already explained how it works for non-overlapping > IP and about the use of IPv6 for UE to UE in general. > > > 1. The UE is assigned a v4v6 PDP context. > 2. The access network from SGSN to GGSN can be IPv6-only network. Here I don't agree, think it is typo. GTP tunnel could be over any type of IP family. > The network can carry both IPv4 and IPv6 UE traffic over this > mobility tunnel. > 3. The tunnel from GGSN and CGN can be IPv6-only transport. > This leaves the access network and the core to IPv6-only, with > traces of IPv4 only on the UE, CGN and GGSN. We just have a > dual-stack UE and with the ability to carry the UE's IPv4 and IPv6 > traffic on the IPv6 network. > 4. Any UE to UE traffic, can always use IPv6. For legacy applications > and when non-overlapping IPv4 addresses are in use, all the UE packets > will hit the mobility tunnel and will arrive at the GGSN. For local > destinations, the GGSN can simply tunnel them to the correct > mobility tunnel, or to the CGN for internet destinations. > 5. For UE to UE over IPv4 and when overlapping addresses are in use, there > is no justification for this case. There is not a single legacy > application that supports this case today. So, it makes more sense to > use IPv6 for this case. Even otherwise, if there are clear requirements > to support UE to UE over IPv4-only and the justification is valid, it > can solved in couple of ways, per Alain's/Dan's draft, using implicit > tunnels. As I replied in the previous email, you are assinging unlimited IPv4 address to the UE, I don't see why you need migrate to IPv6. >> 1) definition of sub-network >> one example could be A: 10.1.1.2 and B: 10.1.1.3, then A knows >> he is in the same sub-network as B. >> >> 2) IPv4 address: Layer 2/v6PDP/v4v6PDP >> Issue 1: In the IPv6 only network, how could it happen? >> > > Your definition of the IPv6 network is the problem. When I say, > IPv6 only network, the UE is dual-stacked and the radio link can > carry both IPv4 and IPv6 packets, but the network from SGSN to > GGSN or from GGSN to CGN is all IPv6. The 3GPP mobility architecture > clearly allows the mobility tunnels to be IPv4 or IPv6, but still > carrying the UE's IPv4 and IPv6 traffic. Note that the traditional > dual-stack, router mode, the UE packets arrive as IPv4 to the > first hop router, still the network is IPv6-only. Same logic here. > Dont confuse IPv6-only network with air link or the dual-stack UE. > We are talking about IPv4 in the routed network. What you described here either SGSN to GGSN, or GGSN to CGN, both of them are bear network which could be closed network, I don't see really deployment about IPv6. > > >> 3）IPv6 prefix: either DHCPv6 or RA >> Issue: No >> > > Good > >> 4) DNS: B must have both A and AAAA record? >> Issue: if A received A and AAAA record, when to use 6-6 >> communication? >> and when to use v4-v6 host to host tunnel? >> > > The standard source address selection rules apply. If the target is > reachable via IPv6, it will use the IPv6, else it will use IPv4. We > are talking about IPv6-only network with IPv6 on all UE's. So, > where ever IPv6 is supported just use it. Per your requirements, IPv6 > is there always and on all UE's. For IPv4-only end points, NAT64 can > also be used. Based on your explanation, I think it is the fundamental issue now, how the host A could smartly identify when and how to use which IP familiy and reachable. > > >> 5) Routing in the A: unconformed? >> if B has both AAAA and A, and B4 is within same sub-network with >> A4, then host to host tunnel >> if B has only A record, and B4 is within same sub-network with A4, >> > > Standard source address selection rules apply as above. Same as above, standard source address selection doesn't apply here. >> 6) Host mdoification: Not clear yet,unconformed (mapping table, DNS) >> A: setup tunnel mapping between IPv4 address and IPv6 address >> B: setup tunnel mapping between IPv4 address and IPv6 address >> Issue 1: when A and B setup the mapping table? mapping table is >> translation? >> A: once received DNS A and AAAA record? >> B: when received the first tunnel packet? >> Issue 2: modify the host to support DNS processing, >> isn't this same as BIS/BIA? >> Issue 3: isn't this same as PNAT in the host? >> > > No changes on the host. I'm not talking about UE to UE over overlapping > IPv4 address scenario. So, dont assume I'm supporting that requirement, > as I said, IPv6 should be used for such non-legacy cases and clearly > when there is IPv6 available. If you want to solve that case, give a > single reason why that is needed. I dont believe its a valid requirement. thanks, for overlapping, you can't support the requirement, back to non-overlapping, you need modify the host, if not please explain how you could support different A/AAA record, thanks -Hui > > >> 7) End to end routing: >> Need go through AR, but not AFTR. >> > > Yes. Local packets will not have to hit the CGN. > > Sri > > > >> Thanks for your checking >> >> -Hui >> _______________________________________________ >> Softwires mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/softwires > _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
