hi
qos implementation deponds on many factors , such as are you using Voice, video in your network, what kind of equipement are you uning , how many exit to the outside network, on which one you wanna apply qos...!
so a basic implementation is as follow , first start classifing you traffic into classes as close as possible to the source of traffic, use
class-map match-all webtraffic
match access-group 101 (where 101 is as follow access-list 101 permit any any eq www)
or
class-map match-all webtraffic
match protocol http (if you equipement support NBAR and CEF)
the switch or the router will create automatically a default class that will hold all the other type of traffic that is not matched in the webtraffic class.
after that create a policy map using policy-map i
policy-map test
class webtraffic
bandwidth 8
class default-class
fair-queue
and apply the service-policy output test under the interface conf mode at the exit point, automaticaly webtraffic will get 8kbps and the other traffic will take the rest which is 75 percent of the total bandwitdh minus 8 kbps, if there is no other traffic or default traffic than web traffic will take more than what you specified but if the link reach its capacity web traffic can not take more than 8Kbps.
HTH
please do rate if does clarify
