Re: 3gpp-analysis: IMS/SIP transition [RE: NAT-PT Applicabilty for 3GPP]

[Pekka Savola <pekkas@netcore.fi>]

On Mon, 17 Nov 2003, Senthil Sivakumar wrote:
> I am not sure what the problem is, either. It is very clear if you
> have a v4 only application/node/network, talking to a v6 only
> application/node/network you need a protocol translator. 

Right (for some definition of translator).

> It is a no
> brainer. Why can't we concede that and move on? The generic protocol
> translator is a transition mechanism and it belongs in this WG.

The question here is, if we don't want a generic protocol translator, 
how could we define a translator very specific to achieve the SIP 
requirements?

At some point there may be a decision which way is preferable,
augmenting NAT-PT by defining a SIP ALG, or specifying a separate
mechanism (which may or may not be using some of NAT-PT concepts).  

The point is, that we should not lock ourselves out of either
possibility at this point, until we see what kind of requirements
SIPPING WG has.

Note to Karim et al: has SIPPING discussed this issue at 
"requirements" level rather than "solutions" level?

Note that our charter says:

  If the satisfactory resolution of an operational or security
  issue requires the standardization of a new, widely-applicable
  transition mechanism that does not properly fit into any other
  IETF WG or area, the v6ops WG will standardize a transition
  mechanism to meet that need.

.. the high-order bit for this debate seems to be, "if we need to get 
a transition mechanism done, try to do it somewhere else (w/ area 
expertise) first; if it fails, do it here".

-- 
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings