Re: IPoIB link address

Hi,
At 03:55 PM 9/22/2003 -0700, H.K. Jerry Chu wrote:
> >Hi,
> >
> >In the IP encapsulation draft , section 6.1.2, it is indicated that the
> >Q_Key used should be that of the
> >broadcast-GID. Which broadcast GID should be used? Specifically, if the
> >IPv4 and IPv6 broadcast GIDs are assigned different Q_keys, which Q_Key
> >should be used?
>
>You should look at the link & multicast draft, not the encapsulation
>draft for the Q_Key assignment. In that draft Q_Key is described as an
>IPoIB link attribute shared by both IPv4 and IPv6. (See section 6.2 IPoIB
>Link Q_Key.)

So what you are saying is that because of what is said in the link & 
multicast draft, the 2 broadcast
groups have to have the same link attributes, i.e. the option #1 indicated 
below is the solution. If this is the case, either draft should at the very 
least make this requirement explicit.

I would prefer to have a single broadcast group for both IPv4 and IPv6 as I 
do not understand the rationale behind requiring the IPoIB driver to 
maintain IP specific information.
-Vandana

> >
> >The issue with potentially allowing different Q_Key values for the 2 GIDs
> >is that 2 separate QPs will have to
> >be allocated for IPv4 and IPv6 traffic respectively and will require the
> >IPoIB driver to keep track of upper layer protocols.
> >If everyone agrees that this is a problem, there are 2 ways to address the
> >issue:
> >1) Require the 2 broadcast GIDs to have the same attributes such as Q_key,
> >MTU etc.
>
>See above. Q_Key and MTU are considered "link" attributes. By definition,
>IPv4 and IPv6 running on top of the same link must use the same set of
>"link" attributes. If this is not clear from the current drafts we can
>certainly fix it. (Well Vivek and I are working on combining the two drafts
>into one. One benefit of the merge is to remove any possible inconsistency.)
>
>Thanks for pointing this out,
>
>Jerry (speaking obviously as a co-author not a co-chair)
>
> >or
> >2) Create a single broadcast GID to define the link.
> >
> >-Vandana
> >
> >
> >
> >_______________________________________________
> >IPoverIB mailing list
> >[email protected]
> >https://www1.ietf.org/mailman/listinfo/ipoverib