Subject: RE: FW: 3gpp scenario 2

From: "Karim El-Malki (EAB)" <[email-masked]>
Date: Wed, 18 Dec 2002 23:28:42 +0100

Hi Pekka

>Let's consider the possible cases here (perhaps it should be clarified 
>which is the case in the particular scenario):
>
>1) inside the GPRS network: if the 3GPP operator has a large backbone,
>it
>may not have native IPv6 everywhere.  Tunneling may have to be used
>there.

This is exactly the case. The tunnelling mechanisms paragraph
mentions explicitly the case where it applies:
    
    In a 3GPP 
    network, one IPv6 island could contain the GGSN while another 
    island contains the operator's IPv6 application servers....

>
>Personally I think this is a non-issue, because as 3GPP is so heavily 
>IPv6, I don't see why anyone would bother deploying it without all the 
>network infrastructure (or most of it so it doesn't really matter) being
>IPv6-enabled.

I don't agree. Most operators already have IPv4 backbone networks and
many would want to migrate them gradually while introducing IPv6
islands. So it does not make sense to base our recommendations on
native IPv6 operator backbones only. The IGP/EGP mechanism is for
the case in which the operator is not ready to upgrade the
backbone.

>
>But if this is important, here something like [BGP][IGP] could be
>usable.  

OK, so I think we agree that this scenario makes sense.

Rgds
/Karim

---

From: Pekka Savola <[email-masked]>
Date: Thu, 19 Dec 2002 00:47:13 +0200 (EET)

>     island contains the operator's IPv6 application servers....

I disagree: it _could_ be a case.

It also reads:

    Encapsulating node can be e.g. the GGSN or the edge router between
    the border of the operator's IPv6 network and the public Internet.

this makes it very apparent to me that main focus was tunneling in the 
internet -approach.

> OK, so I think we agree that this scenario makes sense.

As currently written, I totally disagree.

IGP/BGP tunneling and mechanisms like these are _additional complexity_.

Such mechanisms should not be advocated -- in the face of configured
tunneling which is far superior for a small-to-moderate number of islands 
-- without a lot of care.

IMO there's something really wrong in the 3GPP operator's network if it
needs to have e.g. more than 10-15 isolated IPv6 islands there (~ reaching
one limit where in some cases configured tunneling could become more
difficult to maintain).

btw. the ridiculously long paragraph should be split in about 5.

-- 
Pekka Savola                 "Tell me of difficulties surmounted,
Netcore Oy                   not those you stumble over and fall"
Systems. Networks. Security.  -- Robert Jordan: A Crown of Swords