Limiting ip traffic by protocol, using a 2620 router, PIX515UR and Catalyst

[yeo]

I have an interesting issue I am sure some of you have experienced. Every once in a while a department in my organization wants to email a large number of people, 2000 to 5000, an email that is 1M or larger. Having 2 T1's bonded (joined so the router thinks there is one 3M connection) we have every other bit of ip traffic come to a sreaching halt for several hours as the email servers send the emails out. I am looking for a way to use my 2620 router, PIX515UR or Catalyst 4000 to limit the amount of SMTP traffic allowed out of our system so there is some bandwidth for the other traffic in and out of our network. Is there a way to do this with the 2620 or am I going to have to go with a Packeteer or some other appliance? Any guidance is greatly appreciated.

Thanks

Kevin

[steve.barlow]

You can look into traffic shaping on the router. PIX can't help (it can limit the number of connections to a host but not bandwidth, and it would drop the connections, not buffer them). A shaper typically delays excess traffic using a buffer, or queueing mechanism, to hold packets and shape the flow when the data rate of the source is higher than expected. Some examples are Generic Traffic Shaping (GTS), Class-Based Shaping, Distributed Traffic Shaping (DTS), and Frame Relay Traffic Shaping (FRTS). These can only be applied outbound on an interface.

An example of GTS (http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/12cgcr/qos_c/qcpart4/qcgts.htm ) :

access-list 101 permit udp any any

interface Ethernet0

traffic-shape group 101 1000000 125000 125000 (limit acl 101 to 1Mbs)

An example of class-based (http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fqos_c/fqcprt4/qcfcbshp.htm ) :

Router(config)# policy-map shape

Router(config-pmap)# class c1

Router(config-pmap-c)# shape average 38400 15440 (shape traffic to 384 kbps)

Router(config-pmap-c)# configure terminal

Router(config)# interface Serial 3/3

Router(config-if)# service out shape

Hope it helps.

Steve

[yeo]

This is just what I needed. Thank you very much for the information.