Routing methods, systems, and computer program products

What is this patent about?

’134 is related to the field of network packet forwarding and source-based routing. Specifically, it addresses the challenges of managing network traffic and latency in growing global networks by moving away from traditional destination-based lookups toward a more explicit, path-oriented approach.

The underlying idea behind ’134 is the use of segment routing to encode an entire network path directly into a packet header. Instead of each router independently deciding the next hop based on a global address, the source node pre-calculates a sequence of instructions—represented as a set of identifiers—that dictates the exact route a packet must follow through the network fabric.

The claims of ’134 focus on a system and method where a first node receives path information and generates a set of segment identifiers that uniquely encodes that path. These identifiers are designed to correspond to entries in forwarding tables stored at each segment-routing-enabled node along the route, ensuring that the packet is steered according to the pre-defined sequence.

In practice, the invention works by having the ingress node select between different types of identifiers, such as nodal segment identifiers for specific nodes or adjacency segment identifiers for specific links. By stacking these identifiers in the packet header, the network can implement explicit traffic engineering without requiring every intermediate router to maintain a massive, synchronized state of the entire network's topology.

This approach differs from prior solutions by collapsing the distinction between names, addresses, and routes. While traditional IP routing relies on complex distributed protocols to converge on a path, this path-based protocol address allows for source-defined steering, which significantly reduces the processing overhead at intermediate hops and provides more granular control over network latency and resource utilization.