BGP Metric Data Element Continuity Information
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing Border Gateway Protocol (BGP) lacks a mechanism to accurately determine end-to-end path cost across autonomous systems due to the non-transitive nature of the Accumulated Interior Gateway Protocol (AIGP) attribute, which cannot be propagated when not enabled on neighbor devices.
Innovation Solution
The proposed solution involves a method where BGP network devices generate and send messages containing attribute data with a metric data element that includes continuity information. This information indicates whether each device along the path supports the AIGP attribute and its associated metric data element format, allowing for accurate determination of full or partial accumulated metric values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If the AIGP attribute is used to accumulate metric values across autonomous systems, then end-to-end path cost information can be obtained, but the attribute cannot be propagated when not enabled on neighbor devices, leading to loss of continuity information
Solution Approach 1:
The patent introduces a feedback mechanism where BGP network devices exchange capability information about AIGP support. Each device includes a continuity bit in the metric data element that indicates whether it supports AIGP. This feedback allows devices to understand each other's capabilities and make appropriate routing decisions, resolving the propagation issue without requiring universal AIGP enablement.
Solution Approach 2:
The patent modifies the metric data element format by adding a continuity bit as a new parameter. This parameter change enables devices to convey their AIGP support status within the existing BGP attribute structure, allowing for flexible propagation control without changing the fundamental nature of the attribute.
2Measurement precision
If AIGP attribute propagation is restricted to maintain protocol simplicity, then device complexity is reduced, but accurate determination of end-to-end path cost is lost
Solution Approach 1:
The patent segments the AIGP attribute into two distinct parts: the metric data element containing the accumulated metric value and the continuity bit indicating support status. This segmentation allows the metric accumulation function to be separated from the propagation requirement, enabling accurate path cost measurement while maintaining protocol simplicity through optional participation.
Solution Approach 2:
The continuity bit acts as an intermediary indicator that mediates between devices with and without AIGP support. It allows devices to accurately determine path cost information by conveying capability status, enabling precise measurement without requiring all devices to implement the full AIGP mechanism.
3Reliability
If all BGP network devices must support AIGP to ensure accurate metric accumulation, then path selection accuracy is improved, but network deployment complexity increases
Solution Approach 1:
The patent applies partial action by allowing only a subset of BGP network devices to support and propagate AIGP attributes. Devices that support AIGP can accurately accumulate and propagate metric information, while devices that do not support it simply ignore the attribute. This partial deployment approach maintains path selection reliability for paths through AIGP-capable devices without requiring universal support, thereby easing deployment requirements.
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
In some implementations, a border gateway protocol (BGP) network device may receive from an originator BGP network device via a first other BGP network device, a first message, wherein the first message includes first attribute data associated with a non-transitive attribute, wherein the first attribute data comprises a first metric data element that is associated with a metric data element format and that indicates a metric type, a metric value, and continuity information. The BGP may process the first message to determine first path information associated with a first path from the BGP network device to the originator BGP network device via the first other BGP network device.