Layer 2 RSVP Snooping for Admission Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ethernet switches, being layer 2 devices, lack native admission control capabilities, leading to potential congestion when resource reservations pass through them, as they cannot provide the necessary quality of service, complicating implementation and impacting scalability when trying to extend RSVP for on-path admission control.
Innovation Solution
Implementing RSVP snooping agents in layer 2 devices that intercept and process RSVP messages without requiring IP forwarding functionality, allowing them to interpret and forward RSVP messages, generate error messages, and manage admission control, thereby enabling on-path signaling and admission control without supporting IP forwarding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If RSVP protocol is extended to layer 2 devices, then on-path admission control capability is improved, but device complexity increases
Solution Approach 1:
The patent extracts the RSVP message processing functionality from the full IP forwarding stack. Layer 2 devices implement only the necessary RSVP snooping capability to intercept, process, and forward RSVP messages, while maintaining their original layer 2 forwarding functions. This selective extraction enables admission control without requiring full IP layer implementation.
Solution Approach 2:
The patent enables layer 2 devices to perform multiple functions: traditional MAC address-based frame forwarding and RSVP message processing. By making layer 2 devices universal nodes that can handle both layer 2 traffic and layer 3 RSVP signaling, the system achieves on-path admission control without requiring separate dedicated devices.
2Ease of operation
If layer 2 devices support IP forwarding functionality, then RSVP message processing is improved, but ease of operation deteriorates
Solution Approach 1:
The patent extracts only the essential RSVP message handling capability from the complete IP forwarding stack. Layer 2 devices implement minimal IP processing functionality specifically for RSVP messages (protocol number 46 identification and forwarding), while maintaining their primary layer 2 operations. This selective extraction preserves operational simplicity.
3Reliability
If Ethernet switches implement admission control, then quality of service is improved, but scalability deteriorates
Solution Approach 1:
The patent implements partial admission control functionality in layer 2 devices - specifically RSVP message snooping and resource reservation state maintenance - without requiring full admission control stacks. This partial implementation provides sufficient QoS capability while maintaining scalability across existing Ethernet switch infrastructure.
4Productivity
If RSVP protocol operates at layer 2, then bandwidth efficiency is improved, but device complexity increases
Solution Approach 1:
The patent introduces RSVP snooping agents as intermediary components within layer 2 devices. These agents intercept RSVP messages traversing the switch, process them locally to make admission control decisions, and forward them appropriately. This intermediary approach enables bandwidth-efficient layer 2 RSVP operation without requiring complete architectural redesign of the switching fabric.
Data Source
AI summary
Methods and apparatus for enabling a layer 2 node associated with an open systems interconnection (OSI) reference model to perform resource reservation protocol (RSVP) processing are disclosed. According to one aspect of the present invention a layer 2 device associated with an OSI reference model includes a first interface, a processing arrangement, and a second interface. The first interface intercepts a message associated with a on-path signaling protocol for at least one selected from a group including resource reservation and admission control at a layer above layer 2. The processing arrangement processes the message, and the second interface sends the message.