[e2e] Extracting No. of packets or bytes in a router buffer

Mark Crovella crovella at cs.bu.edu
Wed Dec 13 12:06:09 PST 2006


Hi Craig,

What MIB provides queue sizes?  I am not sure that 'standard' is the
right word when talking about MIBs :).   Maybe some MIBs provide queue
sizes but the one most commonly used in backbone routers (MIB-II, RFC
1213) doesn't provide instantaneous queue lengths as far as I know.  If
I am wrong, please correct me.

People have used measures of queuing delay to infer queue lengths.   I
can't think of a paper that focuses on this, but the general idea is
that queue length in bytes has a relationship to queueing delay and link
bandwidth (factoring in other sources of delays inside routers).

On a sort-of related topic we had a paper a while ago that tried to
estimate queue lengths during packet loss events (ie, to estimate buffer
sizes or RED parameters).  It is 

Jun Liu, Mark E. Crovella (2001).
Using Loss Pairs to Discover Network Properties.
In: Proceedings of the ACM SIGCOMM Internet Measurement Workshop 2001.
pp. 127--138.
http://www.cs.bu.edu/faculty/crovella/paper-archive/imw-losspairs.pdf

- Mark

> -----Original Message-----
> From: end2end-interest-bounces at postel.org 
> [mailto:end2end-interest-bounces at postel.org] On Behalf Of 
> Craig Partridge
> Sent: Wednesday, December 13, 2006 1:55 PM
> To: V Anil Kumar
> Cc: end2end-interest at postel.org
> Subject: Re: [e2e] Extracting No. of packets or bytes in a 
> router buffer
> 
> 
> Queue sizes are standard SNMP variables and thus could be 
> sampled at these intervals.  But it looks as if you want the 
> queues on a per host basis?
> 
> Craig
> 
> In message 
> <Pine.LNX.4.44.0612130958100.28208-100000 at cmm2.cmmacs.ernet.in
> >, V A nil Kumar writes:
> 
> >
> >We are searching for any known techniques to continuously 
> sample (say 
> >at every 100 msec interval) the buffer occupancy of router 
> interfaces. 
> >The requirement is to extract or estimate the instantaneous value of 
> >the number of packets or bytes in the router buffer from another 
> >machine in the network, and not the maximum possible router 
> buffer size.
> >
> >Any suggestion, advice or pointer to literature on this?
> >
> >Thanks in advance.
> >
> >Anil   
> 
> 



More information about the end2end-interest mailing list