Re: draft-bagnulo-pshim6-01.txt

[Deguang Le <[e-mail]>]

marcelo bagnulo braun schrieb:

> 
> El 13/05/2007, a las 20:23, Deguang Le escribió:
> 
>> marcelo bagnulo braun schrieb:
>>
>>> Hi Deguang,
>>> El 13/05/2007, a las 17:37, Deguang Le escribió:
>>>
>>>> Dear Prof. Marcelo,
>>>> page5:
>>>>  When H1 sends the first packet addressed to the CMULA of H2, the
>>>>    packet is intercepted and processed by the P- Shim6 box of the
>>>>    multihomed site.
>>>>
>>>> As above description, H1 sends the first packet, which uses the 
>>>> CMULA of H2 as the destination address. The CMULA is site-local 
>>>> adddress.
>>>>
>>> right
>>>
>>>> Since the destination addresss of the first packet is the CMULA of 
>>>> H2 that belongs to H2's site, I wonder if this packet can be routed 
>>>> in H1's site.
>>>>
>>> this packet is routed to the P-shim box in the H1 site. the P-Shim6 
>>> box of the H1 site will then establish the shim6 context whcih will 
>>> have the CMULAs as ULIDs and regular PA addresses as locators. After 
>>> that it will forward the packets outside H1 site towards H2 site 
>>> containing the PA addresses as locators.
>>> So the packets will carry PA addresses in the IPv6 header once they 
>>> leave the site. CMULAs are only routed inside the local site, so this 
>>> would be compliant with proposed usage of ULAs.
>>> does this address your point?
>>
>> Thank you very much for your detailed explaination. :-)
>> As you said, through the path from H1 to P-shim, the destination 
>> address of this packet is the CMULA of H2, which however is not 
>> routable in the H1's site (the reasions have been listed below). 
>> Normally, the CMULA of H2 can only be routable in the H2's site since 
>> it belongs to site-local address. right?
>>
> 
> right i see your point now.
> 
> the idea is that the P-shim box will inject a route to the CMULA prefix, 
> sinking all packets addressed to CMULA prefix (other than the local 
> CMULA prefix)

Thank you very much!
Do you think whether your idea might violate the specification in 
RFC2374, namley "routers must not forward any packets with site-local 
source or destination addresses outside of the site."

With Best Regards,
Deguang


> 
> then P-shim6 box would replace the CMULA to a globally routable PA 
> address. So the CMULAs would be  routed inside the sites and PA address 
> will be routed in the interdomain
> 
> that makes sense?
> 
> Regards, marcelo
> 
> 
>> Therefore, I only wonder how this packet could be routed from H1 to 
>> P-shim box correctly.
>>
>> With best regards,
>> Deguang
>>
>>
>>
>>> Regards, marcelo
>>>
>>>> The reasions are ss follows:
>>>> According to rfc2373, routers must not forward any packets with 
>>>> site-local source or destination addresses outside of the site.
>>>>
>>>> Reference [12] has the following description:
>>>> Unique Local IPv6 Unicast Addresses are intended for local 
>>>> communications, usually inside of a site.
>>>>
>>>> RFC4193 provides operational guidelines that forbid default routing 
>>>> of local addresses between sites in section 4.1.
>>>>
>>>> By the way, the reference [12] seems have been updated by RFC 4193.
>>>>    [12]  Hinden, R. and B. Haberman, "Centrally Assigned Unique Local
>>>>          IPv6 Unicast Addresses", draft-ietf-ipv6-ula-central-01 (work
>>>>          in progress), February 2005.
>>>>
>>>> Cheers,
>>>> Deguang
>>>>
>>
>