02-04-2006 07:29 AM
Hi there,
I'm trying to figure out how to determine and how to differentiate between control plane and data plane especially in troubleshooting MPLS VPN. Any keyword that distinguish between them? It seems to be confusing for a newbie here :)
Thanks in advance.
maher
02-04-2006 03:22 PM
Hi Maher,
The control plane is simply the set of processes that are responsible for disseminating information on routes, labels etc within a network. This includes routing protocols whose job is to communicate information on routes between different routers. The information provided by these protocols is then used to building routing/forwarding tables.
The data plane is simply an abstraction used to describe the actual flow of data packets using paths determined by the control plane. The control plane traffic carries control traffic (which is not end-user data) whereas the data plane traffic is actual end-user data.
There is no single command that you can use to distinguish between the two. The commands you have on a router that can be used to view control plane operation are as such:
sh ip route
sh ip cef
sh ip bgp ...
sh ip ospf ...
sh mpls forwarding-table...
etc... and many, many more
Typically, there isn't a clear demarcation between commands that display control plane info and those that display data plane information... You could use commands such as the following to get some idea of data traffic flowing through a router:
sh interfaces
sh policy-map interface
etc.
Hope that helps - pls rate the post if it does.
Paresh
02-04-2006 07:17 PM
Hi Paresh,
From here, I can conclude that:
Control Plane:
layer 3 protocol exchange and it's related process like OSPF,BGP,Label distribution.
Data Plane:
Forwarding engine that forwards based on labels or destination IP address like LSP.
Correct me If I'm wrong.
thanks in advance.
maher
02-04-2006 07:26 PM
Hi Maher,
That's a good enough conclusion with the addition that the info used by the forwarding engine to forward packes is provided by the control plane processes.
Paresh
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide