I've got a design question that I've been thinking about, and havent been able to come up with an answer. I'm currently in the process of getting a full DS3 / T3 at one of our companies locations, and I'd like to allocation bandwidth percentages to each network that I've got setup behind the border router. Is there a way to do this?
Basically we'll have 3 seperate networks behind our router, and I'd like to allocate 10Mbps to 2 of the networks, then the rest of the bandwidth to the 3rd network. Is this something that is do-able through QoS policies? The router that we'll be purchasing is a Cisco 3845, to take advantage of the full DS3 line speeds / services.
Any help in this matter would be appreciated.
You can guarantee bandwidth per class on egress or you can police traffic per class on ingress.
Both solutions can be easily accomplished with the hardware you mentioned.
I prefer the guarantee bandwidth per class on egress approach as it allows other subnets to utilize unused bandwidth from other class while inbound policers will restrict the traffic even if there is no traffic in the other subnets.
A high level design would be creating classes that match on those subnets and then assign those classes under a policy-map that either does ingress policing on the physical port facing the internal clients or CBWFQ on the WAN facing physical port.
I highly suggest you become familiar with QoS by reading these documents: