Service Function Chain Topology Discovery via OAM Metadata
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in computer networks is the difficulty in discovering and mapping virtualized service functions that are chained together, as existing methods lack the ability to identify and verify the existence and order of these services across multiple devices or entities, especially with the increasing complexity of large-scale, customized services and the limitations of per-layer Operations, Administration, and Maintenance (OAM) mechanisms.
Innovation Solution
A methodology and apparatus that utilize OAM packets with metadata to traverse service function chains, where request packets are encapsulated with a network service header and metadata is added at each hop to construct a service path from ingress to egress service functions, enabling topology mapping of service chains across multiple devices or entities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If virtualization is used to maintain service functions in a virtual state, then physical resource allocation is reduced and service deployment flexibility is improved, but the ability to identify and discover service functions and their chaining relationships deteriorates
Solution Approach 1:
The patent introduces OAM packets as intermediary carriers that traverse through the service function chain. These packets contain metadata fields that are populated at each service function hop, serving as mediators to convey topology information from virtual service functions back to the discovery source, enabling discovery despite virtualization obscuring physical presence
Solution Approach 2:
The patent implements a feedback mechanism where OAM packets traverse the service chain and return metadata about each visited service function to the discovery source. This feedback loop enables the system to automatically discover and map the topology of virtualized service functions without manual configuration or physical inspection
2Ease of operation
If per-layer OAM mechanisms are used for network maintenance, then layer-specific management is simplified, but the ability to map service chains spanning multiple devices and layers deteriorates
Solution Approach 1:
The patent creates a universal OAM packet structure that can traverse across multiple network layers and service function types. The packet contains a metadata field that can accommodate information from different service functions (firewall, DPI, load balancing, etc.), making the mechanism universally applicable across diverse service chains while maintaining layer-specific operational simplicity
Solution Approach 2:
The patent embeds service function topology information within nested metadata fields inside OAM packets. Each service function adds its identification information to the packet's metadata structure, creating a nested information hierarchy that can be systematically extracted and assembled into complete service chain maps at the discovery source
3Adaptability or versatility
If services are customized and chained on an as-needed basis, then service customization capability is improved, but the complexity of linking and managing various services deteriorates
Solution Approach 1:
The patent enables service chains to self-describe their topology through OAM packets that automatically collect and carry metadata from each service function. This self-service mechanism eliminates the need for external manual configuration or complex management systems, as the service chain itself generates and returns its topology information automatically
Solution Approach 2:
The patent performs preliminary topology discovery by sending OAM packets through service chains before actual service deployment or configuration changes. This preliminary action allows administrators to understand the current service topology and plan customizations or linkages in advance, reducing management complexity during service evolution
Data Source
AI summary
Techniques for mapping a topology of a chain of network service functions on a computer network are described. A request packet is sent to an ingress service function on the network. The request packet is encapsulated with a network service header, which identifies the packet as an OAM packet, and an OAM payload. Where the packet is received by a service function that is not an egress service function, the request packet is forwarded to the next service function hop in the chain. Where the packet is an egress service function, the request packet is returned to the discovery source. A service path is constructed based on the metadata in the OAM payload describing the identified the service functions. This technique can be applied to multiple connected chains to provide a complete mapping of the network topography.