Please imagine a gateway/proxy based network access, the ALTO client is the end host, but actually the IP address for gateway/proxy which connect the end host to the network should be used for ALTO server discovery. The change of end-host IP and gateway/proxy IP is independent somehow. I hope this clarification helps.
BR, -Haibin > -----Original Message----- > From: Scharf, Michael (Michael) [mailto:[email protected]] > Sent: Wednesday, June 20, 2012 8:07 PM > To: Songhaibin > Cc: [email protected] > Subject: RE: [alto] ALTO discovery in roaming scenario > > Haibin, > > The draft already states: > > o A change of the IP address at an interface invalidates the result > of the ALTO server discovery procedure. For instance, if the IP > address assigned to a mobile host changes due to host mobility, it > is required to run the ALTO server discovery procedure for the new > IP address without relying on earlier gained information. > > Could you please explain what text is missing in the draft, and what technical > solution you suggest? For instance, if the mobile network uses "Proxy Mobile > IP"? > > My understanding is that in reality roaming/normadic use results in either of > two > possibilities: > > (1) There is a change of the IP address of the mobile host. This case is > already > explained in the draft. > > (2) The IP address of the mobile host does not change. Then, the host remains > in > the same IP subnet, and thus the ALTO discovery result is still valid. > > In both cases, the current text in the discovery draft seems to be just fine, > right? > > Thanks > > Michael > > > > -----Original Message----- > > From: [email protected] [mailto:[email protected]] On > > Behalf Of Songhaibin > > Sent: Monday, June 18, 2012 1:22 PM > > To: Songhaibin; Richard Alimi > > Cc: [email protected] > > Subject: Re: [alto] ALTO discovery in roaming scenario > > > > I would like to dig this from the tomb and see how the WG > > would like to solve the ALTO discovery in the roaming/nomadic > > scenario. I would also like to see it in the ALTO server > > discovery document. > > > > -Haibin > > > > > > > > > -----Original Message----- > > > From: [email protected] [mailto:[email protected]] > > On Behalf > > > Of Songhaibin > > > Sent: Thursday, March 29, 2012 8:34 PM > > > To: Richard Alimi > > > Cc: [email protected] > > > Subject: Re: [alto] ALTO discovery in roaming scenario > > > > > > Hi Rich, > > > > > > I think your proposal makes sense. The wikipedia document > > > http://en.wikipedia.org/wiki/Mobile_IP provides some links > > to relative > > > RFCs. We may find details in these RFCs. I will also try to > > read them. > > > > > > BR, > > > -Haibin > > > > > > ________________________________________ > > > From: [email protected] [[email protected]] on > > behalf of > > > Richard Alimi [[email protected]] > > > Sent: Thursday, March 29, 2012 8:09 PM > > > To: Songhaibin > > > Cc: [email protected] > > > Subject: Re: [alto] ALTO discovery in roaming scenario > > > > > > On Thu, Mar 29, 2012 at 12:26 AM, Songhaibin > > <[email protected]> > > > wrote: > > > > Hi Rich, > > > > > > > > Thank you for the discussion. See inline. > > > > > > > > ________________________________________ > > > > From: [email protected] [[email protected]] > > on behalf of > > > > Richard > > > Alimi [[email protected]] > > > > Sent: Wednesday, March 28, 2012 11:57 PM > > > > To: Songhaibin > > > > Cc: [email protected] > > > > Subject: Re: [alto] ALTO discovery in roaming scenario > > > > > > > > On Mon, Mar 19, 2012 at 4:28 AM, Songhaibin > > <[email protected]> > > > wrote: > > > >> Hi, > > > >> > > > >> The indicated by the subject, which is perhaps not fully > > solved in > > > >> the discovery > > > draft, I guess at least the following scenarios should be > > considered. > > > As I'm not an expert on roaming technology, please correct > > me if you find I am wrong. > > > >> > > > >> (1) The ALTO client has left its home network, and its > > IP address > > > >> is dynamically > > > assigned by the current network provider (through DHCP or any other > > > method), but the ALTO client still uses its home agent to > > access the > > > Internet. In this case, the ALTO server resided in its home network > > > should be the right ALTO server to be discovered. > > > >> > > > >> (2) The ALTO client has left its home network, and its > > IP address > > > >> is dynamically > > > assigned by the current network provider, and the ALTO > > client uses the > > > foreign agent to access Internet or uses its IP address directly to > > > access Internet. In this scenario, the ALTO server resided > > in the current network should be the right one. > > > And the existing discovery mechanism works in this scenario. > > > >> > > > >> (3) If the ALTO client has a persistent IP address when roaming, > > > >> and it uses > > > home agent to access Internet, but make large data route to the > > > foreign agent directly (optimized routing mode). In this > > scenario, the > > > ALTO server resided in the current network should be the > > right one to > > > be discovered. However, if it does not adopt the optimized routing > > > mode, the ALTO server in the home network should be the right one. > > > >> > > > > > > > > I'm not familiar with the technologies backing this, but > > what entity > > > > decides the route that a particular packet will take? Is this DPI > > > > living in the network where the client is roaming? Or is it some > > > > entity on the client itself? > > > > > > > > [Haibin] No, it is not DPI based. Although I'm not an > > expert on this > > > > either, but I > > > think in the mobile IPv6 scenario, the decision is made through the > > > negotiation among the mobile node, home agent, and other > > correspondent nodes. > > > > > > > > > > Thinking about this at the high level, If the mobile node > > is involved > > > in the negotiation, then it seems like it could work like the > > > following for this case: > > > (1) Discover an ALTO Server using the home agent (same as case 1 > > > above) > > > (2) Discover an ALTO Server using the current network (same > > as case 2 > > > above) > > > (3) When it comes time to apply the ALTO information, apply the > > > correct set depending on the routing for that particular request. > > > > > > Is that compatible with whatever technologies are used for > > these scenarios? > > > > > > Details on how this works and the negotiation actually takes place > > > would be useful. > > > > > > Rich > > > > > > > BR, > > > > -Haibin > > > > > > > >> (4) (this one is not about roaming) Assume in a big > > company which > > > >> has a few > > > branch offices in different locations, and VPN tunnels are used to > > > connect these branch offices, employees use one proxy to access > > > Internet. Then the ALTO server discovery should be based on the > > > proxy's IP address instead of the user's IP address. It > > also applies > > > to other similar scenarios when end-hosts using proxies. > > > >> > > > >> It might not be a problem when doing third party discovery, but > > > >> have to > > > consider when doing the discovery by the end-host itself. > > > >> > > > >> BR, > > > >> -Haibin > > > >> _______________________________________________ > > > >> alto mailing list > > > >> [email protected] > > > >> https://www.ietf.org/mailman/listinfo/alto > > > _______________________________________________ > > > alto mailing list > > > [email protected] > > > https://www.ietf.org/mailman/listinfo/alto > > _______________________________________________ > > alto mailing list > > [email protected] > > https://www.ietf.org/mailman/listinfo/alto > > _______________________________________________ alto mailing list [email protected] https://www.ietf.org/mailman/listinfo/alto
