Subject: Control of host/server processing overload...

From: <[email-masked]>
Date: Fri, 11 Jun 2004 10:09:49 +0100

Hello,

I am interested in understanding if the Internet Traffic Engineering Working Group has considered the following issue: control of processing overload of hosts/servers running protocols such as DNS, LDAP, SIP, HTTP, COPS, SNMP, Radius, and Diameter. 

My impression from a brief trawl is that, within the IETF, much thought has been, and is being, given to the management of bandwidth and router congestion, but almost none to control of host and server processing overload. Indeed, although some of the above listed protocols do provide response or status codes that might be used to indicate processing overload, I have found none which explicitly specifies an overload control mechanism.

The same conclusion also seems to apply to the following non-IETF protocols: H.323, SOAP, SAML, SMPP, and Parlay.

This contrasts with the telephony/ATM world where there are examples of protocols that have built-in overload control features: INAP, ISUP, BICC, PNNI and more recently H.248.11.  Such controls are crucial during extremes of network operation where surges of service requests (or Denial of Service attacks) can be an order of magnitude greater than normal demand levels. 

Please can you advise me of any work that is addressing this area.

Thanks in advance for your help

Martin Whitehead 
BTexact
Performance Engineering
Critical Solutions Performance    
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