The click modular router

Abstract

Click is a new software architecture for building flexible and configurable routers. A Click router is assembled from packet processing modules called elements. Individual elements implement simple router functions like packet classification, queuing, scheduling, and interfacing with network devices. A router configuration is a directed graph with elements at the vertices; packets flow along the edges of the graph. Several features make individual elements more powerful and complex configurations easier to write, including pull connections, which model packet flow driven by transmitting hardware devices, and flow-based router context, which helps an element locate other interesting elements. Click configurations are modular and easy to extend. A standards-compliant Click IP router has 16 elements on its forwarding path; some of its elements are also useful in Ethernet switches and IP tunneling configurations. Extending the IP router to support dropping policies, fairness among flows, or Differentiated Services simply requires adding a couple of elements at the right place. On conventional PC hardware, the Click IP router achieves a maximum loss-free forwarding rate of 333,000 64-byte packets per second, demonstrating that Click's modular and flexible architecture is compatible with good performance.

A distributed mapping control of identifiers and locators for future mobile Internet

“…To validate the proposed DMS scheme, the mapping control operations were implemented using UDP socket programming [13], OpenFlow [14] and Click Modular Router [15] over the Linux platform.…”

Optimized mobile thin clients through a MPEG-4 BiFS semantic remote display framework

“…It is composed of a server and client machine, interconnected by an impairment node. This impairment node is equiped with the Click router framework [16] and allows to simulate the propagation delay between client and server. In order to benchmark the performance of the BiFS prototype, three other open source remote display architectures were installed on the testbed: RealVNC v4.1.1 [27], TightVNC v1.3.10 [37] and FreeNX v3.4.0 [8].…”

A case for run-time adaptation in packet processing systems

“…Examples of applications supported by PPS include Virtual Private Network (VPN), intrusion detection, content-based load balancing, and protocol gateways. Most of these packet processing applications involve multiple types of packets; applications are specified as graphs of functions and the specific sequence of functions invoked for a packet depends on the packet's type (determined based on the packet header and/or payload) [12,16]. For example, a Secure Socket Layer (SSL) [10] application processes three packet types-setup packets (that create per-flow state in the PPS), outgoing packets (that involve encryption), and incoming packets (that require decryption).…”