[e2e] Is RED dead?

[Jing Shen]

Hi,

> 
> I told a couple folks I would follow up with what I
> heard and learned
> off list.  I heard from one person that thought RED.
>  Off list I heard
> that a couple of big providers may use it when links
> become congested,
> and that they will enable it if you ask, but do not
> by default.
> 

> Someone pointed out this useful link containing an
> extensive evaluation
> of AQM schemes:
> 
>   <http://www.cs.unc.edu/~le/>
> 
> In my own experience with some Cisco gear, I suspect
> a fair number of
> people have WRED on a number of interfaces where
> they have turned on
> the QoS knobs for the box, primarily it seems as
> part of a VoIP
> roll-out.

That's may be the key reason for only EF class
implemented in some enterprise networks. But, would
WRED act with EF class traffic ?



  The queueing mechanisms are hardware
> dependent, but on a
> Cisco 6509 Catalyst for example, most modern
> hardware modules come
> with WRED on by default when you turn on 'QoS'. 
> However, since this
> deployment is probably often done within campus
> networks where
> congestion is rare, AQM is probably rarely
> activated.

I'm not sure but to my experience I have to config
packet dropping policy explicity with Cat6509. 

> 
> So... in a nutshell, I feel I had gotten a very weak
> response to this
> question.  Most people just don't seem to care
> enough or have problems
> that really require it to be interested enough in
> RED or related
> mechanisms at this time, but I wasn't convinced it
> was a compromised
> concept.  :-)
> 

IMHO, AQM may be a good tool for 'traditional'
internet environment because there is only 'honest'
TCP applications. In current situation, condition
changes. what I'm not sure is, could AQM be used in
network which need to differentiate e2e service
quality? Could it do much help with those complex
network administration/provisioning problem? 

Jing  



	

	
		
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