Routing Protocol Extensions for Spoke-to-Spoke DMVPN Latency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional Dynamic Multipoint VPN (DMVPN) systems experience significant latency in spoke-to-spoke communication, which is detrimental for delay-sensitive network traffic, due to the reliance on Next Hop Resolution Protocol (NHRP) for next-hop resolution and tunnel establishment.
Innovation Solution
The implementation of routing protocol extensions, specifically enhancing Border Gateway Protocol (BGP) and Enhanced Interior Gateway Routing Protocol (EIGRP) to carry next hop information within extended communities, allowing for immediate address mapping and forwarding entry installation, thereby eliminating the need for NHRP and reducing latency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If NHRP is used for next-hop resolution and tunnel establishment in DMVPN, then spoke-to-spoke communication is enabled, but significant latency occurs which is detrimental for delay-sensitive network traffic
Solution Approach 1:
The patent applies preliminary action by pre-establishing next-hop mappings through routing protocol advertisements before actual spoke-to-spoke traffic needs to flow. The hub router pre-resolves next-hop information and installs forwarding entries in advance, so when traffic arrives, the tunnel is already established or can be immediately activated without waiting for NHRP resolution, thus eliminating latency while maintaining communication capability
Solution Approach 2:
The patent extracts the next-hop resolution function from the NHRP protocol and integrates it into standard routing protocols (OSPF, EIGRP, BGP). By separating the next-hop resolution capability from NHRP and embedding it in routing protocol advertisements, the system eliminates dependency on NHRP for next-hop information, thereby removing the latency associated with NHRP while preserving spoke-to-spoke communication
2Loss of time
If routing protocol extensions are implemented to carry next-hop information, then NHRP becomes unnecessary and latency is reduced, but routing protocol complexity increases
Solution Approach 1:
The patent applies universality by making standard routing protocols (OSPF, EIGRP, BGP) multi-functional. These protocols not only perform their traditional routing functions but also carry and distribute next-hop mapping information through existing protocol mechanisms (such as OSPF external route attributes or EIGRP domain-attached information). This eliminates the need for separate NHRP protocol while maintaining routing protocol simplicity by reusing existing protocol structures for multiple purposes
3Productivity
If next-hop mappings are pre-installed in forwarding tables, then direct spoke-to-spoke forwarding is achieved, but forwarding table size and memory requirements increase
Solution Approach 1:
The patent applies local quality by making next-hop mapping information specific to local spoke routers rather than global. Each spoke router receives and installs only the next-hop mappings relevant to its local forwarding decisions through routing protocol advertisements from the hub. This localized approach enables direct spoke-to-spoke forwarding for relevant traffic while keeping forwarding table sizes manageable by storing only locally-necessary entries rather than all possible spoke-to-spoke mappings
Data Source
AI summary
Systems and methods for using routing protocol extensions to improve spoke to spoke communication in a computer network are disclosed. Embodiments provide systems and methods to establish a tunnel between a first spoke and a hub, exchange routing information between the first spoke and the hub using a routing protocol, extend the routing protocol and an associated database to include next hop mapping information, and establish a tunnel between the first spoke and a second spoke according to information in the database.