Cisco 2651XM router
I'm looking for a sample config or help which would enable me to restrict the speed of traffic of a particular PC on the lan connected to my router.
My lan comprises several PC's on 172.16.1.xx, which connects to f0/0, and internet access for the whole lan is via a wic-adsl card in the router. I did a bit of reading on google about this but found it confusing. I understand I have to set up an access list but as a beginner I'm not sure where to start. I use SDM too but that only seems to cater for traffic going out of the router (unless I'm mistaken). What I'd ideally like to do is be able to pick one machine on the lan (eg PC 172.16.1.15) and restrict the speed of all traffic to and from it to say 50Kb/sec. Is that possible? Thanks for any pointers.
Yes, there's usually serveral methods to restrict bandwidth. First, though, if you "bad" PC is connected to the LAN, you'll likely not be able to easily restrict LAN-to-LAN bandwidth within the same subnet. However, for any traffic being routed to/from the "bad" PC, i.e. to/from other networks including the Internet, that's passing through your 2651XM router, you should be able to throttle it.
Second, you can control all traffic to/from the "bad" PC, treat to/from differently, or also treat different kinds of traffic to the "bad" PC differently. Third, you can drop traffic that's above the rate specified, delay it so it doesn't exceed your specification, or prioritize it relative to other traffic when there's traffic congestion.
Below is an example of using class-based weigthed fair queue to police the traffic to/from the host. (NB: syntax might be incorrect)
ip access-list extended TrafficToBeControlled
remark all IP traffic from "bad" PC
permit ip host 172.16.1.15 any
remark all IP traffic to "bad" PC
permit ip any host 172.16.1.15
class-map match-any TrafficToBeControlled
match access TrafficToBeControlled
interface fastEthernet 0/0
service-policy input CBWFQ
service-policy output CBWFQ
I'm showing usage of CBWFQ as it can be expanded into supporting further traffic management.