IGP Routing Information Reduction via Edge Router Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current systems face challenges in scaling Interior Gateway Protocol (IGP) routing infrastructures due to the need for provider edge routers to maintain extensive state information, leading to increased signaling and messaging overhead.
Innovation Solution
The method involves removing provider edge routers from the IGP process by having them learn routes through internal border gateway protocol (iBGP) and balancing traffic flows without knowledge of network topology, allowing core routers to handle IGP and impose destination routing labels, thus eliminating the need for state information sharing between edge and core routers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If provider edge routers are included in the IGP process to maintain routing information, then routing accuracy and completeness is improved, but signaling overhead and system complexity increases
Solution Approach 1:
The patent segments the routing information management by dividing the network into IGP domain (core routers) and BGP domain (edge routers). Core routers run IGP to maintain topology information among themselves, while edge routers use BGP to learn routes to external destinations. This segmentation eliminates the need for edge routers to participate in IGP, reducing signaling overhead and complexity while preserving routing information completeness through the combination of IGP and BGP protocols.
Solution Approach 2:
The patent extracts provider edge routers from the IGP process entirely. Instead of including all routers (core and edge) in the IGP domain, the invention removes edge routers from IGP and places them in the BGP domain. Edge routers learn routes through BGP from route reflectors rather than through IGP flooding, which eliminates the signaling overhead associated with including edge routers in IGP while maintaining complete routing information through BGP's path vector protocol.
2Measurement precision
If provider edge routers maintain extensive state information for core routers, then routing precision is improved, but messaging overhead increases
Solution Approach 1:
The patent segments the routing information storage responsibility: core routers maintain the complete IGP topology database among themselves, while edge routers maintain only the BGP routing information they need for external destinations. This segmentation eliminates the need for edge routers to maintain extensive state information about core router topology, reducing messaging overhead for LSA flooding while preserving routing precision through the coordinated use of IGP (for core topology) and BGP (for external routes).
Data Source
AI summary
A system and method for routing traffic from an ingress provider edge router to an egress provider edge router that eliminates the need to share state information between the ingress provider edge router and a plurality of core routers in a core network. The ingress provider edge router and egress provider edge router are each coupled to at least two core routers among the plurality of core routers in the core network, the ingress provider edge router learning routes with a next hop equal to an IP address of the egress provider edge router through an internal border gateway protocol (iBGP). The ingress provider edge router balances traffic flows on uplinks between the ingress provider edge router and the at least two core routers coupled to the ingress provider edge router without knowledge of network topology in the core network.