Raj:
Interesting traffic pattern....
If I understand your question, the EF BW is reserved and
leaked into the Ring
It appears as reserved time slots; hence a periodic function?
The question is what is the congestion threshold and when to send congestion
notification. The time scale for congestion detection is important. If
buffers are used, then it is some buffer threshold. Otherwise, is
congestion
detected at cell level, burst level, call level, or days etc.
There is one trade-off for fairness: stability versus maximize BW utilization.
-If you response too fast going into congestion, (reacting to small
burst), you are susceptible to instability and you BW efficiency
may be reduced.
-If you response too slow, you will not be fair, as some node may get
starved.
-If you response too fast in existing, you may not be fair again, and
you oscillate.
-If you response too slow in existing, you loose efficiency.
Regards,
Harry
Khaled Amer wrote:
Raj,
Not sure I understand how you reached
to the conclusion of 'the traffic at any node would be a periodic function'.
Can you shed some light on this?
Khaled Amer
President, AmerNet
Architecture Analysis and Performance Modeling Specialists
Phone: (949)552-1114
13711 Solitaire Way, Irvine, CA 92620
Fax: (949)552-1116
e-mail: khaledamer@xxxxxxx
----- Original Message -----
Sent: Wednesday, August 16, 2000 9:36
AM
Subject: EF% vs. BCN
I
would like to findout if anyone has giventhought
to Explicit Forward (EF) traffic versus BCN mechanismsused
on buffer insertion rings.Assume
that x% of the BW is provisioned for EF.As
EF traffic into the ring it will given highest priorityforwarding
and hence to culminate in all EF packets arriving
together. The BW consumed by EF traffic overtime
can become a time function. Example
x(t) = sine or square wave function of t with an amplitudeof
x.As
a consequence available BW for the
rest of the traffic at any node
can become a periodic function. There
could be interplaybetween this
perdiodicity and the periodicity of the
congestion notification messages.Has
anyone simulated this or have given thought tothis?
--
Harry Peng
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