VTEP NAT Synchronization for SDN Packet Forwarding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing data packet forwarding methods in software-defined networks (SDNs) face inefficiencies due to multiple encapsulation and decapsulation operations across different SDNs, which complicate communication between virtual machines and hinder seamless address translation.

Innovation Solution

Implementing a method where a VXLAN Tunnel End Point (VTEP) device configures a NAT function and reports NAT mapping relationships to the SDN controller, which synchronizes and stores these mappings across SDNs, enabling efficient VXLAN encapsulation and decapsulation, and performing Network Address Translation (NAT) processing to facilitate communication between virtual machines.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple encapsulation and decapsulation operations are performed across different SDNs, then address translation between private networks can be achieved, but communication efficiency deteriorates and device complexity increases

Engineering Contradiction:
Improveaddress translation capabilityVSAvoidcommunication efficiency
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The patent extracts the NAT function from traditional gateways and relocates it to VTEP devices within the SDN architecture. This allows address translation to be performed at the network edge where VXLAN encapsulation occurs, eliminating the need for separate NAT devices and reducing the number of encapsulation/decapsulation operations required across SDN boundaries.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The VTEP device is designed to perform multiple functions simultaneously: VXLAN encapsulation/decapsulation, NAT address translation, and flow table management. By consolidating these functions into a single device, the patent eliminates the need for separate NAT gateways and reduces communication overhead between multiple network devices.

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

2Adaptability or versatility

If NAT function is implemented at gateway devices, then address translation between private networks is enabled, but device complexity and communication overhead increase

Engineering Contradiction:
Improveaddress translation capabilityVSAvoidnetwork device complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent merges the NAT function with the VTEP device, combining address translation capabilities with VXLAN tunnel endpoint functionality. This consolidation eliminates the need for separate NAT gateway devices and reduces the complexity of network device interconnections while maintaining full address translation capability between private networks.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The VTEP device performs multiple functions including VXLAN encapsulation, decapsulation, NAT address translation, and flow table management. This multi-functional approach reduces the total number of network devices required and simplifies the overall network architecture by eliminating dedicated NAT gateways.

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

3Reliability

If flow tables are synchronized across multiple SDN controllers, then NAT mapping consistency is maintained, but communication time and system complexity increase

Engineering Contradiction:
ImproveNAT mapping consistencyVSAvoidflow table synchronization time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent implements preliminary action by pre-synchronizing NAT mapping relationships between SDN controllers before data packet forwarding is required. Flow tables are populated with NAT mapping information in advance, allowing VTEP devices to perform rapid lookups without real-time synchronization delays during actual packet forwarding operations.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system implements feedback mechanisms where VTEP devices report flow table status and NAT mapping changes to SDN controllers, which then synchronize updates across the network. This feedback loop ensures consistency while allowing for efficient update propagation only when changes occur, rather than continuous synchronization.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3313025B1Data packet forwarding
Publication Date: 2022.03.23 NEW H3C TECH CO LTD
  • EP3313025B1 patent drawingFigure 1~2
  • EP3313025B1 patent drawingFigure 3
  • EP3313025B1 patent drawingFigure 4~5

AI summary

A SDN controller obtains and stores a NAT mapping relationship between a private network address and a public network of a host computer in each SDN; receives a flow table request for a data packet from a VTEP device, searching for a NAT mapping relationship corresponding to a target IP address of the data packet when determining that the data packet is forwarded across SDNs; generates a flow table used for forwarding the data packet according to the NAT mapping relationship corresponding to the target IP address searched out and network topology information, and transmits the flow table to the VTEP device, wherein the flow table comprises a NAT processing instruction for a source IP address and encapsulation information, and a target IP address in the encapsulation information is a public network address in the NAT mapping relationship searched out.