Re: Question on IPv6 over IB

On Thu, 20 Jan 2005, Nitin Hande wrote:

> 
> > Vivek> Isn't the length of the option already 8 when used on
> > Vivek> Ethernet (type+length+ 48bit)? Then it wouldn't require the
> > Vivek> padding.
> > 
> > Of course you are correct.  The 6 octet length of the ethernet address
> > confused me, sorry.
> > 
> >     Vivek> Will it not align the local address at 2 byte boundary as
> >     Vivek> against 4?
> > 
> > That's true.  It seems there is some precedent for putting the padding
> > at both ends: IPv6-over-ARCnet (RFC 2497) puts the (one octet!?)
> > ARCnet address at the beginning of the option followed by 5 octects of
> > padding, while IPv6-over-Fibre Channel (RFC 3381) puts two octets of
> > padding at the beginning followed by 12 octets of address.
> > 
> > I will generate a patch for the Linux kernel to pad appropriately and
> > forward it to the networking maintainers.
> > 
> > Does anyone know what Solaris's IPoIB implementation does?
> > 
> Looking at the source code, Solaris is inserting the padding at the end
> after the Link Layer address. Given the release phase that Solaris is
> in, it will be difficult to change that implementation at this point.
> Obviously, if OpenIB decides to implement padding at the start of the
> link address,it will cause incompabilility between Solaris and OpenIB.

It will cause incompatibility between Solaris and the RFC :).

Vivek

> 
> Thanks
> Nitin
> 
> 
>