Ensigma’s programmable Wire-Speed Switching and Routing (WSP) solutions are highly scalable and configurable for various applications, enabling network connectivity, switching and routing. They offer complete offload of TCP/IP processing at the hardware level to achieve higher data rates without burdening the host processor. The WSP architecture guarantees wire-speed secure routing of any size packets between Gigabit Ethernet ports. The architecture is highly scalable for multiple Ethernet ports or peripherals with other protocols.. The hardware/software partitioning and the partitioning of software between host processor and embedded modules ensure that WSP software can be easily integrated into a customer’s existing software.

Ensigma’s WSP is an enterprise class modular, scalable network software module for managed home/SMB gateways, routers, switches to perform Layer 2 – Layer 4 switching and routing. It significantly accelerates the performance of common protocols like DNAT, SNAT, VLAN and PPPoE in host processor based communication processors. It implements sophisticated QoS algorithms amenable for both software-only and coprocessor-based hardware implementations. Ensigma’s WSP performs state-full classification / modification / scheduling of packets to achieve higher throughput across multiple ports. The slow path of the software sets up tables to aid the fast-path processing of packets. It provides framework for advanced protocols like IPSec and for processing advanced Application Level Gateways (ALG). The architecture allows a very high number of flows without any degradation in performance and supports numerous industry-standard RFC’s and protocols. Ensigma’s WSP is developed as a loadable kernel module for Linux operating systems for facile integration.

Ensigma NPU

Architecturally as shown in the figure above, a System would have a MIPS like Host Processor running control and certain datapath functions, the datapath is offloaded by a cluster of Micro-Aptive type of Processors, Supported by a set of configurable hardware functions. Finally the hardware functions communicate to the external world using a set of standard interfaces. Ensigma Network Processors perform datapath functions by implementing the software and hardware for bottom three layers architecture.

Switching and Routing Solutions

With fibre to the home, node and basement, the functionality and complexity of a gateway processor and Ethernet switches increase significantly. The current generation of gateway architectures implemented in CPE is not addressing multi gigabit data rates with growing functionality. The next generation of architectures would need to:

  • Route multi-gigabits of data
  • Provide sophisticated Quality of Service for applications like IPTV and VoIP
  • Handle a very high number of flows
  • Be implemented in an ultra-low-cost device adaptable to mass markets
  • Be highly programmable for changing requirements
  • Enable VPN and deep packet inspection to protect against attacks

WSP is a highly programmable processor. The architecture includes a hardware QoS engine to achieve scalable and guaranteed performance. Functions including packet classification, deep packet inspection and modification are programmable using multiple 32-bit RISC engines(CLASS). The architecture features hardware assists for scheduling and reordering packets to the programmable engines. The blocks are connected using a proprietary bus for optimal throughput and highest performance with smallest area. The architecture provides separate busses for data transfers and control packet communication. It provides flexible performance that scales with internal memory and packet classification performance. The architecture is suited to low-cost home-gateway SoC devices and shares a unified memory with the on-chip host.

Software Architecture

The WSP architecture is a fast-path/slow-path state full architecture. The hardware blocks and the Processing Elements (PEs) in the Classifier block implement the fast-path and the host processor performs the slow-path. Ensigma’s software suite features the fast path code, the adaptation of the Linux kernel using net filters, etc. and the drivers to configure the hardware. Both the firmware and software supports Linux IP Contracts and ALGs implementing firewall functions etc.

The API for the low level blocks is provided such that the integration is facile with any operating system. The software organization is as below and it is colour coded to indicate the modules that are modified from standard Linux and the modules that are developed by Imagination.


Ensigma’s Switching and Routing IP blocks are deployed in various network gear.

  • Wireless Access Point (Switch)
  • Enterprise/Residential GW (Eth + Sec)
  • IP Set-Top-Boxes
  • Small Cell Base-Station
  • Micro Servers



  • Scalable Architecture
    • Switching Solutions
    • Routing Solutions
  • Area Scales with Performance
  • Best Area Vs Performance Metric
    • 4 sqmm + 3 sqmm per Gbit
  • Complete Solution
    • Software, Firmware and Hardware solution
    • Firewalls / ALG
    • IPV4, IPV6, NAT
    • PPPoE, VLAN
  • Hardware based QoS
    • Scheduling
    • Shaping
  • Programmable Classification and Packet Editing

Protocols Supported

The WSP Solution supports various protocols in the networking Stack. Additional protocol support can be provided as a customization of PE Code.

  • Switching/Bridging
  • RoutingVLAN
  • IPV4
  • IPV6
  • NAT
  • PPPoE
  • L2TP / PPTP
  • G.8032
  • 1588v2
  • VM Switching
  • Open Flow

Performance and Tools

Ensigma’s provided tools are used to determine the number of Processing Elements, Internal memory required and the external Memory bandwidth required for the processing required number of packets per sec and data rate.