[e2e] not quite the differentiated services I was thinking of

[Jing Shen]

> 
> Rather than setting priorities on a per-application
> basis, I think the
> more reasonable approach is to simply sell users
> SLAs and allow them
> to use what they're buying however they wish. There
> are all kinds of
> pricing schemes that can prevent users from "hogging
> the network,"
> while remaining application-agnostic.

The problem is, DiffServ mechanisms ( queueing,
bandwidth allocation ) introduce too much of
difficulties into ISP networks. An simple example, if
we enable traffic classification and multiple queues
in  ISP networks, QoS differentiation shows up only
when congestion happens; DiffServ tries to solve
bandwidth competition under congestion situation, ISP
want to differentiate e2e QoS even when bandwidth is
overprovisioned! 

Somebody may say ISP should make their network
bandwidth utilization level just around the threshhold
of congestion, but that's not applicable no matter in
service planning or in network management.  

As it is stated in the article Folk forwarded, ISPs
tries to management traffic in their network; But, it
should be clear that the ultimate target is to gain
more profit; Skype or those IP telephone provider
escape from the cost of network construction and
management, but they got a large part of market from
Telephone companies who may pay a lot of effort in
broadband network establishment and mainteinance. So,
such traffic should be managed or blocked. To my
understanding , WRED or current DiffServ mechanism
does not fit to such requirement at all.

Jing 


	

	
		
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