The networking paradigm locator/identifier split decouples locating and identifying functionality of addresses. Thereby it improves multi-homing, fail-over, mobility, traffic engineering over the Internet, and routing scalability.The Locator/Identifier Separation Protocol (LISP) is a prominent incarnation of that paradigm which recently became an Internet standard. However, existing LISP implementations are either proprietary or have limited performance, which makes their deployment difficult in high-speed networks. Programming Protocol-independent Packet Processors (P4) is a programming language that facilitates the implementation of custom data plane processing on high-performance switches with line rates of up to 400 Gbit/s.In this work, we present P4-LISP, an open-source P4-based proof of concept implementation of a high-performance LISP router. It supports all relevant features such as ITR, ETR, RTR, P-ITR, P-ETR, NAT-traversal, LISP-NAT, and mobile nodes. As control plane, the open-source implementation lispers.net has been integrated on the switch. Security features are added to protect the control plane from being overloaded by the high-performance data plane. The paper describes the architecture of P4-LISP in detail and extensively evaluates performance, functionality, controller performance, and overload protection.

Tag switching is a way to combine the label-swapping forwarding paradigm with network-layer routing with particular application to the Internet. This has several advantages. Tags can have a wide spectrum of forwarding granularities, so at one end of the spectrum a tag could be associated with a group of destinations, while at the other end, a tag could be associated with a single application flow. At the same time, forwarding based on tag switching, due to its simplicity, is well suited to high-performance forwarding. These factors facilitate the development of a routing system that is both functionally rich and scalable. Last, tag switching simplifies the integration of routers and asynchronous transfer mode switches by employing common addressing, routing, and management procedures.

The purpose of multicast routing is to reduce the communication costs for applications that send the same data to multiple recipients. Existing multicast routing mechanisms were intended for use within regions where a group is widely represented or bandwidth is universally plentiful. When group members, and senders to those group members, are distributed sparsely across a wide area, these schemes are not efficient; data packets or membership report information are occasionally sent over many links that do not lead to receivers or senders, respectively. We have developed a multicast routing architecture that efficiently establishes distribution trees across wide area internets, where many groups will be sparsely represented. Efficiency is measured in terms of the router state, control message processing, and data packet processing, required across the entire network in order to deliver data packets to the members of the group. Our protocol independent multicast (PIM) architecture: (a) maintains the traditional IP multicast service model of receiver-initiated membership, (b) supports both shared and source-specific (shortest-path) distribution trees, (c) is not dependent on a specific unicast routing protocol, and (d) uses soft-state mechanisms to adapt to underlying network conditions and group dynamics. The robustness, flexibility, and scaling properties of this architecture make it well-suited to large heterogeneous internetworks.

Existing multicast routing mechanisms were intended for use within regions where a group is widely represented or bandwidth is universally plentiful. When group members, and senders to those group members, are distributed sparsely across a wide area, these schemes are not efficient; data packets or membership report information are occasionally sent over many links that do not lead to receivers or senders, respectively. We have developed a multicast routing architecture that efficiently establishes distribution trees across wide area internets, where many groups will be sparsely represented. Efficiency is measured in terms of the state, control message processing, and data packet processing, required across the entire network in order to deliver data packets to the members of the group.