Re: [RTG-DIR] [lisp] Rtgdir last call review of draft-ietf-lisp-gpe-04

["Adrian Farrel" <[e-mail]>]

Hello Dino,

> > No attempt is made in the document to explain how/why the reduction in size
> > of some standard LISP header fields is acceptable. For example, if
> > implementations of this spec can safely operate with a 16 bit Nonce or 8 bit
> > Map-Versions, why does 6830/6830bis feel the need for 24 and 12 bit fields
> > rspectively?
> 
> Note, you misread RFC6830. The Map-Version field is 24-bits when the V bit is
> set. And is divided up like this:
> 
>     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>     |N|L|E|V|I|flags|  Source Map-Version   |   Dest Map-Version    |
>     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>     |                 Instance ID/Locator-Status-Bits               |
>     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

I don't think I missed that even slightly.
The Map-Version field is 24 bits and split into two 12 bit Map-Versions (source
and dest).
When the P-bit is set, the Map-Version is reduced to 16 bits and is (presumably)
split at 8 bits each for source and dest (see my new text).

So my question could be seen as:
Why does this document only need 8 bits for Source Map-Version when 6830 needed
12 bits?

Cheers,
Adrian