Source MAC Address Encoding for SDN Downlink Forwarding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing centralized forwarding architecture in Software Defined Networks (SDNs) requires significant storage space for flow tables, limiting network simplification and efficiency, especially in large enterprise networks with increasing traffic and real-time service demands.
Innovation Solution
A method that configures a downstream forwarding path for terminal devices by generating a source MAC address based on the forwarding path, allowing forwarding switches to route packets without labels or stored entries, thereby reducing costs and improving efficiency by using the source MAC address to indicate the forwarding path and priority.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a centralized forwarding architecture is used in SDN, then network traffic can be simplified and controlled, but large storage space is required for flow tables
Solution Approach 1:
The patent extracts the forwarding path information from traditional flow table entries and embeds it directly into the source MAC address of data frames. This removes the need for large flow tables while maintaining centralized control, as the forwarding path is now carried within the packet itself rather than stored in external tables.
Solution Approach 2:
Instead of storing forwarding rules in centralized flow tables and matching packets against them, the patent inverts the approach by encoding the forwarding path directly in the packet's source MAC address. The switch then simply reads this embedded path information rather than performing table lookups, fundamentally reversing the traditional SDN forwarding mechanism.
2Ease of operation
If flow tables are used for forwarding, then forwarding control can be achieved, but forwarding efficiency is reduced due to storage and lookup requirements
Solution Approach 1:
The patent extracts forwarding path information from centralized flow tables and embeds it directly into the data frame's source MAC address. This eliminates the need for switches to perform table lookups, thereby maintaining forwarding control while significantly improving forwarding efficiency by removing the storage and lookup overhead.
Solution Approach 2:
The controller performs preliminary action by calculating the downstream forwarding path and encoding it into the source MAC address before packets are forwarded to switches. This pre-computation and embedding of path information eliminates the need for real-time table lookups at switches, thereby improving forwarding efficiency while maintaining control.
3Loss of information
If labels are used to indicate forwarding paths, then path identification is achieved, but device complexity and cost increase
Solution Approach 1:
The patent makes the source MAC address multi-functional by using it not only for standard source identification but also for encoding the downstream forwarding path. This eliminates the need for separate labels while maintaining path information, thereby reducing device complexity without losing path identification capability.
Solution Approach 2:
The patent merges the forwarding path indication function with the source MAC address field. Instead of using separate labels alongside the MAC address, the path information is combined into the source MAC address itself, reducing device complexity while preserving complete path information for forwarding decisions.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
This application provides a downstream packet sending method, a downstream packet forwarding method, a downstream packet sending apparatus, and a downstream packet forwarding apparatus. The downstream packet sending method in this application includes: configuring a downstream forwarding path of a downstream packet for a terminal device; generating a source MAC address based on the downstream forwarding path, where the source MAC address is used to indicate the downstream forwarding path; and sending the downstream packet to a forwarding switch, where the downstream packet includes the source MAC address. This application can reduce costs, improve efficiency, and simplify network traffic.