MPLS: Forwarding using FIB and LFIB

To forward packets LSRs use the CEF FIB and the MPLS LFIB.  Both the FIB and LFIB holds label information as well as the outgoing interface and next hop information.

FIB is used to forward unlabeled packets – IOS matches the destination IP to the best prefix in the FIB and forwards the packet

LFIB is used to forward labeled packets – IOS compares the incoming label to the LFIB list of labels and forwards the packet based on the LFIB entry




Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s