Overlay Traffic Forwarding Control via Tunnel-Based Policy Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In overlay networks, there is a lack of centralized control over traffic forwarding paths, limiting the ability to intervene or control forwarding decisions, especially in scenarios where network devices cannot find matching routing entries.
Innovation Solution
A control device receives packets from network devices through tunnels, determines forwarding policies based on routing entries, and sends these policies back to the network devices to manage and control the forwarding paths, considering factors like link quality and security levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a distributed network architecture is used without centralized control, then devices can independently learn and determine forwarding paths, but the network lacks overall control capability and cannot intervene in forwarding decisions
Solution Approach 1:
The patent segments the network control function by introducing a control plane separate from the data plane. The control plane includes a controller that centrally manages forwarding policies, while the data plane consists of forwarding devices that execute these policies. This segmentation allows independent forwarding decisions at the device level while maintaining centralized control capability at the controller level, resolving the contradiction between operational independence and centralized control.
Solution Approach 2:
The controller acts as an intermediary between the centralized control requirements and distributed forwarding devices. It receives forwarding policy requests from forwarding devices, determines appropriate policies based on network state, and returns control instructions. This intermediary mechanism enables both independent device operation and centralized control intervention without requiring direct peer-to-peer communication between all network elements.
2Adaptability or versatility
If overlay network virtualization is implemented, then cloud resource pooling capability is enhanced, but the physical network becomes less controllable from an entire network perspective
Solution Approach 1:
The patent introduces a logical control dimension above the physical network layer. The controller operates in this logical dimension, receiving encapsulated packets from forwarding devices, determining forwarding policies in the logical space, and returning instructions. This dimensional addition allows the physical network to maintain its virtualization capabilities while the logical control plane provides comprehensive network-wide controllability, resolving the contradiction between adaptability and controllability.
3Productivity
If routing information is actively spread by control devices using protocols like BGP EVPN, then network devices can normally forward packets, but the control device cannot intervene or control the forwarding path
Solution Approach 1:
The controller performs preliminary action by pre-determining forwarding policies and storing them in a forwarding policy database before packets arrive. When a forwarding device sends an encapsulated packet, the controller retrieves the pre-determined policy from the database and returns the control instruction. This preliminary preparation enables both efficient packet forwarding and subsequent control intervention capability, as the control decisions are already prepared in advance.
Solution Approach 2:
The system implements feedback by having forwarding devices send encapsulated packets containing service packet information back to the controller. The controller processes this feedback, determines appropriate forwarding policies based on network state and pre-stored routing entries, and returns control instructions to the forwarding devices. This feedback loop enables continuous control intervention while maintaining normal packet forwarding operations.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A method for controlling traffic forwarding, a device, and a system are provided. The method includes: A control device receives a first packet sent by a first network device, where the first packet includes a first service packet. A destination of the first packet is the control device, a destination of the first service packet is first user equipment, and the first user equipment is connected to a network by using a second network device. Then, the control device determines a first forwarding policy based on the first packet and a first routing entry, where the first forwarding policy is used to guide forwarding of a first data flow to which the first service packet belongs. In addition, the control device sends the first forwarding policy to the first network device. In this way, the control device implements, based on a packet sent by a network device, intervention and control on a forwarding path of a data flow to which the packet belongs.