L2GW Border Control for Scalable Virtual Layer 2 Networks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current network structures face scalability issues and resource exhaustion due to ARP flooding and complex configuration requirements when establishing and maintaining Layer 2 networks across multiple locations, particularly in environments that do not support MPLS and in scenarios with large numbers of hosts and VMs.
Innovation Solution
A scalable mechanism using a border control mechanism and protocol-independent address resolution to connect multiple Layer 2 networks across locations, employing L2GWs that maintain local IP address tables and proxy ARP functions to facilitate address translation and forwarding, reducing the burden on the network and supporting multicast groups.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If ARP flooding is used for address resolution in Layer 2 networks, then address resolution can be achieved, but network scalability deteriorates and resource exhaustion occurs
Solution Approach 1:
The patent introduces ARP mediation devices (L2GWs) as intermediaries between hosts in different Layer 2 networks. These mediators intercept ARP requests, perform address resolution on behalf of hosts, and return resolved addresses, thereby eliminating the need for ARP flooding across the entire network while maintaining address resolution functionality.
Solution Approach 2:
The patent extracts the ARP flooding mechanism from the core network and relocates address resolution functions to border devices (L2GWs). By taking out the problematic ARP flooding from the network interior and handling address resolution at the network boundary, the system maintains address resolution capability while preventing resource exhaustion in the core network.
2Reliability
If complex tunnel configurations are used to connect Layer 2 networks, then network connectivity can be established, but configuration complexity and management burden increase
Solution Approach 1:
The patent implements self-service mechanisms where L2GWs automatically discover other L2GWs, autonomously establish forwarding relationships, and dynamically update address mappings. This automation eliminates the need for manual tunnel configuration and reduces management complexity while ensuring reliable network connectivity.
Solution Approach 2:
The patent employs preliminary action by having L2GWs pre-establish forwarding tables and prepare address mapping structures before actual communication begins. This preliminary setup automates the connectivity establishment process and simplifies subsequent network management without compromising connectivity reliability.
3Area of stationary object
If Layer 2 networks are extended across multiple locations, then network coverage is improved, but ARP flooding and resource exhaustion worsen
Solution Approach 1:
The patent segments the extended Layer 2 network into multiple virtual Layer 2 networks, each bounded by L2GWs. This segmentation confines ARP traffic to individual segments and prevents ARP flooding from propagating across the entire multi-location network, thereby preserving network resources while maintaining broad coverage.
Solution Approach 2:
The patent introduces L2GWs as intermediary devices at network boundaries that intercept and resolve ARP requests before they can flood across multiple locations. These intermediaries enable network coverage extension while preventing resource exhaustion by localizing address resolution to boundary devices.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An apparatus comprising a service network and a plurality of Layer 2 networks at a plurality of different physical locations coupled to the service network via a plurality of edge nodes at the Layer 2 networks, wherein the edge nodes are configured to maintain a plurality of Internet Protocol (IP) addresses of a plurality of hosts across the Layer 2 networks, and wherein the IP addresses of the hosts in each of the Layer 2 networks are mapped by the other Layer 2 networks to a Media Access Control (MAC) address of each of the edge nodes in the same Layer 2 networks of the hosts.