BGP MPLS MAC VPN Control Plane Learning

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current MPLS VPN technologies are unable to support active-active L2 connectivity for customer edge devices and struggle with load-balancing and scalability across multiple data centers, while also allowing for seamless relocation of virtual machines without renumbering or readdressing.

Innovation Solution

The implementation of BGP MPLS-based MAC VPNs, which enable L2 MAC address learning in the control plane through inter-device signaling, allowing for multi-homed, active-active L2 VPN connectivity and supporting hundreds of thousands of hosts across multiple data centers, while minimizing unknown unicast traffic flooding and enabling virtualization.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If regular Ethernet switching technologies with MAC learning are used, then L2 connectivity is provided, but the same MAC address cannot be learned from two different PE routers simultaneously, preventing multi-homed active-active connectivity

Engineering Contradiction:

Improvemulti-homed active-active connectivityVSAvoidMAC address learning mechanism

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent introduces BGP signaling as an intermediary mechanism to mediate MAC address learning across multiple PE routers. Instead of relying on traditional data-plane MAC learning that prevents duplicate MAC addresses from different sources, BGP signaling in the control plane acts as a mediator that allows multiple PEs to advertise and learn the same customer MAC addresses simultaneously, enabling active-active multi-homed connectivity without the constraints of traditional switching mechanisms

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the traditional data-plane MAC address learning mechanism with a control-plane BGP signaling mechanism. This substitution allows the system to overcome the inherent limitation of Ethernet switching where a MAC address table can only associate one interface per MAC address, by using BGP routes to advertise MAC addresses with additional path information, thereby enabling multiple active paths to the same MAC address

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Adaptability or versatility

If traditional MPLS VPN technologies are used, then L3 connectivity is provided, but L2 connectivity with active-active connectivity and load-balancing is not supported

Engineering Contradiction:

ImproveL2 active-active connectivityVSAvoidconnectivity availability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent extends the functionality of BGP signaling beyond its traditional L3 routing role to also support L2 MAC address learning and advertisement. By making BGP a multi-functional protocol that handles both L3 routing and L2 MAC address management, the system achieves active-active L2 connectivity while maintaining the reliability and scalability of MPLS VPN infrastructure

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent moves MAC address learning from the data plane to the control plane, adding a new dimension to the VPN architecture. This dimensional shift allows MAC addresses to be advertised as BGP routes with additional attributes (such as Ethernet segment identifiers and PE router identifiers), enabling multi-dimensional MAC address resolution that supports active-active connectivity and load-balancing across multiple paths

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Productivity

If control plane BGP signaling is used for MAC address learning, then multi-homed active-active connectivity and load-balancing are enabled, but protocol complexity increases

Engineering Contradiction:

Improveload-balancing capabilityVSAvoidcontrol plane signaling protocol

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent segments the BGP MAC address advertisement into distinct components including Ethernet segment identifiers (ESI), PE router identifiers, and MAC address fields. This segmentation allows each component to be independently managed and processed, reducing the complexity of handling complete MAC address advertisements while enabling sophisticated load-balancing and multi-path routing decisions based on individual segment attributes

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS8953590B1Layer two virtual private network having control plane address learning supporting multi-homed customer networks

Publication Date: 2015.02.10 JUNIPER NETWORKS INC

AI summary

This disclosure describes techniques for supporting an and Multi-Protocol Label Switching (MPLS)-based Virutal Private Network (VPN) service that provides layer two (L2) connectivity between the customer edge device. In particular, the techniques support a Border Gateway (BGP) MPLS-based MAC VPNs (“MAC-VPN” or “MAC VPN”). The techniques provide a MAC VPN in which L2 MAC address learning occurs in the control plane via inter-device BGP signaling in the control plane rather than the data plane, in response to VPN traffic, as may be typical with other VPN technologies.