Switching Device Packet Processing Using Prefix-Based Bit Field Matching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The processing efficiency of generic matching in OpenFlow networks is relatively low due to the need to extract and match bit fields with every generic flow entry in the flow table, leading to repeated operations and reduced performance.
Innovation Solution
A switching device acquires a prefix and uses it to extract a bit field for matching, creating a correspondence between the prefix and generic flow entries, allowing the bit field to be matched once and reused across multiple entries, thereby reducing the number of extractions and improving processing efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If generic matching is performed by extracting and matching bit fields with every generic flow entry in the flow table, then comprehensive packet classification is achieved, but processing efficiency deteriorates due to repeated operations
Solution Approach 1:
The patent applies preliminary action by pre-extracting bit fields from packets and storing them in a buffer before matching against generic flow entries. This allows the same bit field to be reused across multiple matching operations without repeated extraction, directly resolving the technical contradiction by eliminating redundant extraction operations and improving processing efficiency
Solution Approach 2:
The patent creates copies of extracted bit fields and stores them in a buffer for subsequent matching operations. Instead of repeatedly extracting the same bit field from the original packet, the system uses stored copies, reducing the extraction operation count and thereby improving productivity while reducing time loss
2Measurement precision
If bit field extraction and matching is performed for every generic flow entry, then accurate packet classification is achieved, but device complexity increases due to multiple extraction operations
Solution Approach 1:
The system performs preliminary extraction of bit fields and stores them in a buffer before the matching phase. This separates the extraction operation from the matching operation, allowing accurate classification to be maintained while reducing device complexity by eliminating redundant extraction logic from the matching loop
Solution Approach 2:
The patent segments the packet processing into distinct phases: extraction phase where bit fields are extracted and stored in a buffer, and matching phase where stored bit fields are compared against flow entries. This segmentation maintains classification accuracy while simplifying the overall device complexity by organizing operations into modular, non-redundant stages
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
Embodiments of the present invention provide a packet processing method, device and system. The method includes: receiving, by a switching device, a packet, where there is a correspondence in the switching device between a prefix and a generic flow entry, where the correspondence is created by using the prefix as an index, and a match field of the generic flow entry corresponding to the prefix includes the prefix; acquiring, by the switching device according to the prefix, a bit field that is in the packet and that is used for matching; and performing matching, by the switching device, between a value of the bit field and a data parameter of the match field of the generic flow entry corresponding to the prefix. The embodiments of the present invention can reduce a quantity of times of generic field extraction from a packet and improve processing efficiency.