MPLS – It’s fun..
My MPLS studies are getting on nice. I am finally getting a good idea of what is going on and understanding how this beast works. My first techincal post is here.
MPLS has two major components
The Control Plane
The Data Plane
The control plane looks afterthe routing information and the exchange and the label exchange. It build the routing table based on the protocol, this is called the RIB (routing information base) The RP’s could be RIP, EIGRP, OSPF, IS-IS or BGP. The control plane can manage all of these RP’s.
The control plane uses a label exchange protocol to create/maintain labels for internal use and to be able to exchange the labels with other devices. It does this by binding labels to networks it has learnt via a RP. Today we mainly use LDP (label distribution protocol).
Also the control plane build two fowarding table called the FIB (it does this from the information it learned from the RIB) the table is called the LFIB (label fowarding information base).
The second is the data plane (also refered to as the fowarding plane) looks after the fowarding, this is based on either the destination address or the labels. This is a simple (boy i like it when Cisco refer to stuff as simple!) fowarding engine that is independent of the different types of routing protocol or label exchange being used. The data plane fowards packets to the interface, based on the information from the LFIB or FIB table.
Get these two cast in you mind and what and why these two components are so important to MPLS and it makes the whole thing that bit easier.
Awesome news this week was i was made moderator on Todd Lammle’s forum. A great hounor this is, Todd is a great friend to me and if three years ago when i first bought his CCNA book someone told me i would be able to call Todd a friend and be a moderator for him i would have laughed.
Study gives me the munchies, i have a tub of ice cream in the freezer.