RE: FW: 3gpp scenario 2

["Karim El-Malki (EAB)" <Karim.El-Malki@era.ericsson.se>]

 > On Thu, 19 Dec 2002, Karim El-Malki (EAB) wrote:
 > >  > Sure, but my thought is that dual-stack v4/v6 backbones 
 > >  > already exist, and
 > >  > are definitely on the rise.  It's not like 3GPP networks are 
 > >  > deploying
 > >  > today or tomorrow.
 > > 
 > > I think the issue was that 3GPP core networks have already 
 > been deployed
 > > and are running IPv4.
 > 
 > .. but v6 part of it isn't deployed today or tomorrow.  Prudent folks
 > would be preparing for enabling of IPv6 today -- so that when finally
 > viable 3GPP solutions are available, their network is 
 > already upgraded,
 > router software tested etc.

True you want to prepare as early as possible. However you may want to
do your initial deployment without risking to disrupt your live v4
network. You can do that without upgrading your backbone.
Of course the final aim is to upgrade the backbone, but I don't
think we should recommend that they must go dual-stack from day one
if they don't want to.

 > 
 > >  > Often setting up the infrastructure required to
 > >  > install something like BGP/IGP tunneling is greater 
 > than the pain of 
 > >  > configured tunneling or dual-stack backbone.
 > > 
 > > When an operator introduces v6 islands over an existing v4 backbone
 > > it doesn't have to modify the existing network. Both configured
 > > tunnelling and EGP/IGP would be the same from this point of view.
 > 
 > .. at the expense of possibly having to upgrade latest and greatest 
 > software in the islands to support these mechanisms.

The v6 islands haven't been deployed yet so that's ok.

 > 
 > > In certain cases upgrading the whole backbone at once is worse.
 > 
 > Who says the backbone must be upgraded at once?  Usually 
 > things like these
 > are done over a longer period, e.g. 6-12 months.

What I'm saying is that there may be operators that don't want to
risk disrupting a live network in the early stages of ipv6
deployment. They would do that when they have more experience with
running the v6 network. For those in this situation they can tunnel
between the v6 islands in the early stages. So it is a scenario we need
to consider IMO.

/Karim