Subject: Re: [mobile-ip] Handover Smoothing - What to Do?

From: "Charles E. Perkins" <[email-masked]>
Date: Sat, 04 Aug 2001 08:57:50 -0700

Hello Pat,

>> Just for clarification, duplicate packets already occur in
>> the network.
>>
>> So, why is the possibility of creating duplicates at the
>> edges, during a
>> handoff - which is infrequent - now become a real problem, when they
>> already occur in the network without handoffs?
>>
>> PatC

You point out that the network already creates duplicate packets.
For every such occurrence, bicasting becomes quadricasting and
suddenly we have a problem.

Thus, bicasting works better when the rest of the network can be
trusted not to produce duplicate packets.

Put another way, bicasting removes the resiliency which exists
today for TCP traffic.

My conclusion is that any use of bicasting needs to be strictly
limited in time, with well-defined start and stop times.  The
ability to define these start and stop times is crucial, and yet
whenever it is possible to do so, it might equally well be possible
to design protocol so that unicast packets go where they ought to go.

Regards,
Charlie P.

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From: Pat Calhoun <[email-masked]>
Date: Mon, 6 Aug 2001 01:16:56 -0700

> to design protocol so that unicast packets go where they ought to go.

That sounds reasonable.

PatC