[e2e] Scheduling, was: Re: end2end-interest Digest, Vol 19, Issue 5

[Detlef Bosau]

I´ve just seen that we talk about different concepts in "opportunistic
scheduling". 

In a very first stage of PTE, I thought about the problem similar to
that tackled by Thieryy (however not that formal) and that forgot about
this 
for the moment.

One problem tackled in Thierry´s paper is (please correct me if I´m
wrong) the problem of different connection qualities. Of course, it´s a
problem if a mobile with a bad connection usurps the whole channel for
retransmissions whereas a mobile with a good channel get´s no time
slots.

>From a first glance, the PF algorithm (which is enhanced by Thierry)
chooses a packet from a flow which achieved small throughput in the past
whereas packets from flows with high throughput are postponed. 

This concept still resides totally in the "packet switching domain".

What I had in mind was that mobile networks often combine packet
switching and line switching. E.g. GPRS fully resides within the GSM
technology and the GPRS packet channel(s, there are lots of channels
there) are multiplexed with the voice channels. So, the time slot
allocation must first satisfy the
requirements for voice scheduling and afterwards packet channels may be
sent. Voice is given priority over data. 

So, at the moment, I thought about "half a layer deepr" then Thierry.

Just to say that. Otherwise a term like "scheduling conflict" would make
no sense. What I was talking about was the problem to allocate a
data channel cell in presence of voice traffic.

However, I would be glad if someone could help me here, because I always
have difficulties to understand the details of GSM etc., the
multiplexing
algorithms are horrible complex.


Detlef

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Detlef Bosau
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