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

From: James Kempf <[email-masked]>
Date: Fri, 27 Jul 2001 10:39:09 -0700 (PDT)

>
>Perhaps I am missing something (or did a poor job of explaining what I had in
>mind).. However, in your above illustration, during T(1) when you are 
downloading,
>what if there is nothing to buffer ?
>
>

Sure, but you can't design a network based on the premise that
sometimes there won't be anything to buffer. What happens if there
is? 

I think both smoothing techniques have a lot of problems and need
lots more study. 

		jak

---

From: Rajeev Koodli <[email-masked]>
Date: Fri, 27 Jul 2001 11:19:16 -0700

> sometimes there won't be anything to buffer. What happens if there

Well, if you design it assuming that there will always be something to buffer,
you have a worst-case bound, which in a statistically multiplexed network (such
as an IP network), is an overkill. I brought up the case of talkspurt and idle
periods to elucidate this. The network dynamics, i.e., how the queuing in a
tandem network affects the inter-packet separation, clearly plays into this.
Given the complexity, what folks typically do is to size up client buffers based
on what is tolerable for each application. For instance, real-time voice has
fewer buffers compared to streaming. This is bit of an art, not exact science.

> I think both smoothing techniques have a lot of problems and need

Sure. Until then, let's work towards moving FMIP forward!

Regards,

-Rajeev