Methods, systems, and computer program products for routing using headers including a sequence of node scope-specific identifiers

What is this patent about?

’327 is related to the field of network routing and packet forwarding, specifically within Multiprotocol Label Switching (MPLS) environments. It addresses the limitations of traditional global addressing schemes, such as IPv4 and IPv6, which face scalability issues and increasing latency as networks expand. The invention proposes a shift from identifying 'where' a node is located to defining 'how' to reach it by utilizing path-based information rather than fixed global addresses.

The underlying idea behind ’327 is the use of a path-based protocol address composed of a sequence of identifiers that are specific to the local context of each node along a route. Instead of a single global identifier, the system uses a chain of node scope-specific identifiers, where each segment of the address only needs to be meaningful to the node currently processing the packet. This allows for a highly efficient, source-routed approach where the path is baked into the packet header itself, reducing the need for complex global routing tables at every intermediate hop.

The claims of ’327 focus on a current node in an MPLS network that identifies a specific sequence of these scope-specific identifiers to reach a destination. The node extracts the first identifier in the sequence to determine the immediate next hop and then generates a modified header containing only the remaining identifiers. By transmitting the data with this truncated sequence, the current node ensures that the next node in the path receives a header where its own relevant local identifier is now at the front of the queue.

In practice, this mechanism functions like a self-navigating map where each instruction is discarded once followed. When a packet arrives at a router, the device looks at the leading scope-specific identifier, which might simply be a local port number or a short index unique to that router's neighborhood. Because the identifier is local to that specific node's address space, the same bit pattern could represent entirely different physical paths when encountered by a different router later in the sequence, allowing for massive address reuse across the network.

This approach differentiates itself from prior art by effectively merging the concepts of naming, addressing, and routing into a single nested protocol address. Unlike standard MPLS which relies on label distribution protocols to set up paths in advance, this invention allows for dynamic path selection based on policy or real-time network conditions at the source. By utilizing interface-based identifiers that are optimized for size and processing speed, the system minimizes header overhead and eliminates the lookup latency associated with massive global routing databases.