BGP Peer Label Stack Consolidation for FIB Scale Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current BGP protocols face inefficiencies when binding MPLS labels to address prefixes, leading to increased MPLS FIB entries and processing complexities, especially in large multi-domain networks, which can result in hardware limitations and scalability issues during routing re-convergence.
Innovation Solution
A method where a BGP peer device receives a control plane message with a network address, prefix, and label from a downstream peer, generates a new message with its own network address and a label stack including the received label and a local label, and updates the forwarding information base, optimizing label usage and processing by retaining and prepending locally assigned labels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If BGP protocols bind MPLS labels to address prefixes in large multi-domain networks, then routing functionality is achieved, but the number of MPLS FIB entries increases leading to hardware limitations and scalability issues
Solution Approach 1:
The patent combines multiple label binding operations into a single consolidated FIB entry. Instead of creating separate FIB entries for each label-prefix binding, the invention merges them into one entry that handles multiple labels, thereby reducing the total number of FIB entries and alleviating hardware limitations in large multi-domain networks.
Solution Approach 2:
The patent makes a single FIB entry universal by enabling it to handle multiple MPLS labels for different address prefixes. This multi-functional approach allows one FIB entry to serve multiple routing purposes, reducing the overall number of entries needed and improving scalability without compromising routing functionality.
2Loss of information
If BGP protocols process and update routing information in large multi-domain networks, then complete routing information is maintained, but processing complexities increase during routing re-convergence
Solution Approach 1:
The patent merges multiple routing information updates into a single consolidated processing operation. When routing re-convergence occurs, instead of processing each label binding separately, the invention combines them into one update operation, thereby maintaining complete routing information while significantly reducing processing complexities during dynamic routing changes.
3Reliability
If BGP speakers assign local labels for each next hop, then label uniqueness is ensured, but scale pressure on BGP speaker local label space increases
Solution Approach 1:
The patent merges the label space requirements by allowing a single local label to serve multiple next hops through the consolidated FIB entry mechanism. This approach maintains label uniqueness where needed while reducing the overall scale pressure on BGP speaker local label space by eliminating redundant label assignments.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The use and processing of update messages (e.g., BGP UPDATEs) that bind (e.g., MPLS) labels to address prefixes is improved such that labels are used more efficiently, and/or such that such update messages can be processed more efficiently. A distance vector control signaling protocol (e.g., BGP) peer device receives a control plane message (e.g., BGP Update) from a downstream peer device, the control plane message including (1) a network address of the downstream device as a next hop value, (2) a prefix value, and (3) at least one label associated with the prefix value. Responsive to receiving the control plane message, the peer device generates a new control plane message including (1) a network address of the peer device as a next hop value, (2) the prefix value from the control plane message, and (3) a label stack including (i) the at least one label from the control plane message, and (ii) a local label associated with the peer device. The peer device then sends the new control plane message to an upstream peer device.