18 Jul 2006 02:07
Re: MR received the HAAD Reply (R flag=0)
Vijay Devarapalli <vijay.devarapalli <at> azairenet.com>
2006-07-18 00:07:02 GMT
2006-07-18 00:07:02 GMT
let me see if I understand this right. you have two home agents on the home link one of which supports mobile routers and the other does not. K.Kawaguchi wrote: > HA0 HA1 MR R1 MR > | | | | > | | | | > | | |>>>>>>>>>>>>>>>| 1. MR move to foreign link > | | | | > | | <-------------------- | 2. Binding Update > | | | | (Hflag=1, Rflag=1, Lifetime>0) > | | | | > | | --------------------> | 3. Binding Acknowledgement > | | | | (Status=0, Hflag=1, Rflag=0, Lifetime>0) > | | | | > | | <-------------------- | 4. Home Agent Address Discovery Request > | | | | (Rflag=1) > | | | | > | | --------------------> | 5. Home Agent Address Discovery Reply > | | | | (Rflag=0, Address=HA1, HA0) even though the DHAAD reply is from HA1, the Rflag should be set to 1 since If a Home Agent receives a Dynamic Home Agent Discovery request message with the Mobile Router Support Flag set, it MUST reply with a list of Home Agents supporting Mobile Routers. The Mobile Router Support Flag MUST be set if there is at least one Home Agent supporting Mobile Routers. since there is at least one HA (HA0) that supports mobile routers on the same link, the Rflag should be set to 1. however this assumes that HA1 has support for mobile routers (implementation wise) but has the mobile router support currently turned off. RFC 3963 does not support the case where there is a MIP6 HA (which was never upgraded) and a NEMO HA on the same link and the DHAAD request comes to the MIP6 HA. the MIP6 HA would never have processed the R flag in the home agent information option in the router advertisement from the NEMO HA. we can try to fix this when 3963 is revised. in case the MR consistently gets a DHAAD reply with the Rflag set to 0, then it should assume that there are no HAs with mobile router support on the home link. your test case seems to want the mobile router to try each HA on the home link by sending a binding update with the Rflag set to 1. this was never the intention in the spec (but a mobile router could be configured to do this). hope this helps. Vijay > | | | | > | | <-------------------- | 6. Binding Update > | | | | (Hflag=1, Lifetime=0) > | | | | > | | --------------------> | 7. Binding Acknowledgement > | | | | (Status=0, Hflag=1, Lifetime=0) > | | | | > | <---------------------------- | 8. Binding Update > | | | | (Hflag=1, Rflag=1, Lifetime>0) > | | | | > | ----------------------------> | 9. Binding Acknowledgement > | | | | (Status=0, Hflag=1, Rflag=1, Lifetime>0) > | | | | > > > Best regards > --- > Kiyoaki KAWAGUCHI kawaguti <at> ysknet.co.jp > > > > "Re: [nemo] MR received the HAAD Reply (R flag=0)" > "Andy Huang <hpanda <at> huawei.com>" wrote: > >> I wonder whether any HA can work as RFC3775-HA and RFC3963-HA at the same >> time. >> It seems that there are no constraints on this point. >> >> ----- Original Message ----- >> From: "K.Kawaguchi" <kawaguti <at> ysknet.co.jp> >> To: <hpanda <at> huawei.com>; <nemo <at> ietf.org> >> Sent: Friday, June 16, 2006 8:36 AM >> Subject: Re: [nemo] MR received the HAAD Reply (R flag=0) >> >> >>> Hi, >>> >>> Do you mean to exclude the possibility that RFC3775-HA includes NEMO-HA >>> in the HA List with (R) flag=0? I also think that RFC3775-HA should be >>> excluded from NEMO Home Link. In　a word, all HA supports RFC3963. >>> However, I was anxious about this possibility. Need not MR basically deal >>> with this possibility? >>> >>> >>> Best regards >>> --- >>> Kiyoaki KAWAGUCHI kawaguti <at> ysknet.co.jp >>> >>> >>> >>> In message <027f01c6907d$3ae7cf60$ce2da40a <at> china.huawei.com> >>> "Re: [nemo] MR received the HAAD Reply (R flag=0)" >>> "Andy Huang <hpanda <at> huawei.com>" wrote: >>> >>>> According to RFC3963, it mean that there is no HA which can support MR on >>>> the home link. >>>> And I think it's useless for MR to get MIP-HA list from the DHAAD reply >>>> when >>>> R Flag in the packet is 0. >>>> >>>> ----- Original Message ----- >>>> From: "K.Kawaguchi" <kawaguti <at> ysknet.co.jp> >>>> To: <nemo <at> ietf.org> >>>> Sent: Thursday, June 15, 2006 3:40 PM >>>> Subject: [nemo] MR received the HAAD Reply (R flag=0) >>>> >>>> >>>>> Hi, >>>>> >>>>> I have a question about RFC3963 section 5.3, 7.2. >>>>> >>>>> The HAAD Reply indicates that the MR Support (R) Flag is 0 >>>>> and the list of HA Addresses include many HAs. >>>>> How to process the Mobile Prefix Registration when MR received >>>>> the HAAD Reply. >>>>> >>>>> I assumed the following processing. >>>>> Is there the correct one? Or, another one? >>>>> >>>>> 1. MR tries the Mobile Prefix Registration to HAs in order >>>>> of list of HA Addresses. >>>>> 2. Almost same as above 1. But MR skips the HA that sent the >>>>> HAAD Reply. >>>>> 3. MR send the HAAD Requiest again until finding NEMO-HA. >>>>> 4. MR doesn't try the Mobile Prefix Registration. >>>>> 5. In fact, there are no matter since this situation is avoided >>>>> by the following some solution. >>>>> eg, >>>>> - MIP Home Link and NEMO Home Link should be separated. >>>>> - If MIP Home Link and NEMO Home Link are the same link. >>>>> - It should be configure to reply by NEMO-HA rather than by >>>>> MIP-HA. >>>>> (The HAAD Reply function of MIP-HA isn't enabled.) >>>>> - Even if HA don't support MR, HA should support the RFC3963. >>>>> (This MIP-HA supports the RFC3963. MIP-HA makes the (R) flag 1 >>>>> and the list of HA Addresses except for MIP-HA.) >>>>> >>>>> >>>>> Best regards >>>>> --- >>>>> Kiyoaki KAWAGUCHI kawaguti <at> ysknet.co.jp >>>>> >>>>> Best regards >>>>> --- >>>>> Kiyoaki KAWAGUCHI kawaguti <at> ysknet.co.jp >>>>> >>>>> >>>>> >>>> >>>> >>>> >>> >>> Best regards >>> --- >>> Kiyoaki KAWAGUCHI kawaguti <at> ysknet.co.jp > >
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