Is there a recommended practice for determining the best QoS burst setting when policing on an (ethernet) interface over a WAN circuit...so you get the best throughput as as close to the cir as possible?
Say you have a 20MB wan circuit and want to police a certain type of traffic to say 5MB we can say this is web traffic. What would be a way to determine the best burst speed for optimal throughput for the policed traffic allowing up to the cir speed.
I assume you are trying to determine the burst size for the 5mb policed-rate.
Policing will keep the traffic-rate at the specified value, and will not exceed it. It will be as close to the cir as possible as long as there is traffic to be sent out.
It all depends on the Tc. The default value is 125ms, which means that for a 5mb rate, each 125ms will send 625kbps of traffic. This is good for data traffic (in this case, http) because it is not much affected by serialization.
For networks that have voip implemented, it is recommened to use a Tc of 10ms, to prevent serialization delay because of the line-rate speed compared to the policed burst.
please rate the answer if that satisfies your question.
So just to clarify my understanding you are basically saying for traffic such as web traffic just taking the defaults weather I am policing at 2MB, 5MB, or whatever...should work fine?
Here is a sample config I am considering.
class-map match-any police match access-group name police class-map match-any parent match class-map police ! ! policy-map police class police police cir 5000000 conform-action transmit exceed-action drop class class-default fair-queue random-detect policy-map parent class class-default shape average 20000000 service-policy police ! ip access-list extended police permit ip any any eq 80
int fa0/0.100 bandwidth 20000 ip address x.x.x.x x.x.x.x service-policy out parent
On an ethernet sub-interface you must shape using a parent policy-map then apply a second policy-map which contains your QOS settings attached to their respected class-maps.
You shape all the traffic to tell the interface how much traffic you are allotted from the provider. Then you use a second policy-map for your QOS settings that's applied to the parent. In my example I will actually be policing a couple of other traffic types and not just the one type in the example.
Here's are a couple of links that somewhat explains it.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.