Firewall Mark Routing Table Selection in Policy Based Routing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In Policy Based Routing (PBR) systems, the selection of routing tables becomes slow due to the large number of PBR rules, leading to increased complexity and management burden, especially when hundreds or thousands of rules are involved, and traditional techniques fail to provide efficient packet classification and routing table selection.

Innovation Solution

A method and network device that generate a Firewall Mark (fwmark) including a network domain indication and packet classification indication, which determines a match with PBR rules to select the appropriate routing table, significantly speeding up the routing table selection process and reducing the number of PBR rules required, thereby improving performance and management efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If traditional PBR rule matching is used for routing table selection, then comprehensive packet classification and routing control can be achieved, but routing table selection speed becomes severely reduced due to the large number of PBR rules

Engineering Contradiction:
Improverouting table selection speedVSAvoidPBR rule management complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The patent introduces a firewall mark (fwmark) as an intermediary value that bridges packet classification and routing table selection. The fwmark is generated by classifying packets based on multiple criteria (source/destination IP, ports, protocol) and then used as a key to quickly identify the appropriate routing table, avoiding direct comparison against hundreds or thousands of PBR rules while maintaining comprehensive classification capabilities

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system performs preliminary packet classification to generate the fwmark before the actual routing table selection process. This preliminary classification groups packets into categories that can be quickly mapped to routing tables, so that when routing decisions are needed, the system only needs to match the pre-computed fwmark rather than re-evaluating all classification criteria against multiple routing rules

Inventive Principle:
Principle #10Preliminary action

2Adaptability or versatility

If hundreds or thousands of PBR rules are used to cover multiple network domains, then comprehensive routing control is achieved, but the burden on managing RPDBs increases significantly

Engineering Contradiction:
Improvenetwork domain coverageVSAvoidRPDB management ease
Core Design Contradiction:
Adaptability or versatilityVSEase of operation

Solution Approach 1:

The patent merges multiple packet classification criteria (source IP, destination IP, source port, destination port, protocol type) into a single fwmark value. This consolidation allows the system to maintain comprehensive multi-domain routing control while reducing the management burden, as the fwmark serves as a unified key that encapsulates all classification dimensions without requiring separate rules for each criterion combination

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The fwmark mechanism serves multiple functions simultaneously: it classifies packets, identifies routing tables, and provides a compact representation of complex packet characteristics. This multi-functionality allows a single data structure to replace what would otherwise require multiple separate PBR rules, simplifying RPDB management while maintaining comprehensive routing control across diverse network domains

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Measurement precision

If each packet is compared against a large number of PBR rule selectors, then accurate routing table selection can be made, but routing table selection speed becomes severely reduced

Engineering Contradiction:
Improverouting table selection accuracyVSAvoidpacket processing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent extracts the essential classification information from complex PBR rule comparisons and encapsulates it in the fwmark. Instead of comparing each packet against numerous PBR rule selectors, the system extracts packet characteristics into the pre-computed fwmark and uses this compact representation for rapid routing table identification, maintaining selection accuracy while dramatically reducing processing time

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP3632064B1Routing table selection in a policy based routing system
Publication Date: 2023.01.11 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
  • EP3632064B1 patent drawingFigure 1
  • EP3632064B1 patent drawingFigure 2
  • EP3632064B1 patent drawingFigure 3

AI summary

A method implemented by a network device for selection of a routing table in a Policy Based Routing (PBR) system is described. The method may include receiving a packet from a first network domain; generating a firewall mark for the packet, wherein the firewall mark includes a network domain indication and a packet classification indication; determining a match between the network domain indication of the packet and a selector of a matched rule in a set of rules; and upon determining the match between the network domain indication of the packet and the selector of the matched rule, inputting the firewall mark to a function of the matched rule to identify a routing table for the packet.