From old times,
I have studied Diffserv and made an experiment in Linux kernel 2.4.x
but I have a question?
At first, supposed the input link capacity of diffserv's edge(ingress)
router is
more capacity than output link.
that is, total e1's input BW is 20Mbps, total e1's ouput BW is 10Mbps
s1 ---------l
10M l
l----------- e1----------e2 ------------- d1
l 10M ^ 10M 10M
s2 ----------l l
10M l
l
edge router (e1)
--------------------------
l input : output l
l part : part l
l : l
--------------------------
At second, s1 host sends AF1(2.5M), AF2(2.5M), AF3(2.5M), AF4(2.5M) -
that is , total 10M traffic - to d1 host.
s2 host sends best effort (6M) traffic to d1 host.
total sending traffic is 16M.
At this time, both the user s1, s2's traffic is not guaranteed in
existing tc architecture
because the result of s1,s2 traffic metering is not marked in the e1's
input part,
queue of e1's output has only a FIFO queue.
As this output's sch_dsmark has a FIFO queue, Best effort traffic and AF
classes traffic is combined and does not guaranteed AF classes.
Existing sch_ingress and sch_dsmark architecture in edge router(e1) is
following that...
http://dcn.ssu.ac.kr/~peniel5/zboard/zboard.php?id=diffserv
here, input device uses sch_ingress, output device uses sch_dsmark
as you see, mark of the traffic(af) is end part ( output device ) in this
picture.
Therefore, in this circumstance, I think that existing TC structure in
Linux kernel 2.4.x is not availble.
Do you have another idea?
I think wrong thing?
well.. I think I have right idea.
and.. finally,
I have a suggestion!
To solve these demerits, I made ingress marker in linux kernel 2.4.x.
that is, I take DSCP marking part 's position in input device part .
the result, architecture of these experiments and performance test
( existing architecture VS suggested architecture )
showed in my web board
my web board is
http://dcn.ssu.ac.kr/~peniel5/zboard/zboard.php?id=diffserv
I hope your opinion !!!!!
<<attachment: winmail.dat>>
