Mobile Network Technical Challenges

["m.willson1" <m.willson1@ntlworld.com>]

Paul et al

I've (at last) had the time to go through the MISP requirements internet
draft.  In general think the draft provides a useful summary of the
requirements that a IP framework needs to support for mobile networks.
I have a few observations  that I hope may be useful.

I think the section on  Fundamental Technical Challenges is important
for the community to understand the drivers that make mobile networks
different from fixed.  A couple of points which are not clear to me:

The draft talks about supporting transport handoff between technologies
and refers to macrodiversity.  Isnt this exclusive to a particular
technology i.e. effectively part of the radio access (physical link).

What is meant by determining how link loss is detected - in advance or
after the event.  I assume this tries to differenetiate between the
radio data link informing the higher layers of a loss of connectivity
and layer 3 signalling to say that the data link no longer meets the
required QoS or there is a better data link available and handover may
be an option.

Also in the following section on Wireless Internet Access Frameworks it
is said that 3GPP does not embrace MobileIP for support of Mobile IP
routeing.  Perhaps this needs more qualification. I think in this case
embrace implies that MobileIP is used internally within the mobile
network at least for Macromobility.  Whereas 3GPP already defines some
degree of interworking with MobileIP based networks.

Mick