bandwidth limiting

you can rate limit the interface bandwidth on a cisco IOS by :

1- using the rate-limit command:
under the interface (-if)#rate-limit conform-action exeed-action violate-action

this is a usefull, easy to implement command, but hte problem it is not suppported on all interface types (like some router SPA interfaces).

2- using QoS traffic policing or traffic shaping:

first, creat an access list for the targeted hosts
(router)#access-list 10 permit 10.10.10.0 0.0.0.255

then, creat a class-map
(router)#class-map match-any BW-LIMIT
(router-c)#match access-group 10
exit

after that, define a policy map which will refer to the class you've just created:
(router)#policy-map BW-POLICY-LIMIT

than place a call for the class-map inside the policy-map:
(router-pmap)#class BW-LIMIT

doing that, you're now ready to specify the bandwidth limits, here you can choose (police, shape, bandwidth,...), i prefer to choose the shape command:

(router-pmap-c)#shape average 4000000 ; here i limit the bandwidth to 4 Mbps

the final step is to assign this policy (i.e. service policy) to an interface:

(router-if)#service-policy BW-LIMIT-POLICY
end

i hope that was informative