Questions?   (0265)2290300

Nomus eMux

1,2,4 or 8 E1 Pseudowire Access Gateway

 The Nomus eMux is a Pseudowire access device which transports 1, 2, 4 or 8 Framed or Unframed E1s as encapsulated packets over Ethernet Public Switched Networks (PSNs). The eMux supports UDP/IP, MPLS or plain Ethernet encapsulation to meet varied transport infrastructure. It supports the industry standard CESoPSN (RFC 5086), TDMoIP (RFC 5087) & SAToP (RFC 4553) for pseudowire emulation of Framed & Unframed E1 Channels. Thus, PSN networks based on GPON, xDSL, Wireless or WiMAX can be used to transport Legacy TDM based voice traffic efficiently & economically. In addition, the ExoP supports a V.3 5interface to transport HDLC data over PSN using HDLCoPSN (RFC 4618). Multiple Ethernet Ports offer Ethernet access as well.

Application Diagram 



E1 transport over PSN

  • Legacy TDM voice transport of 1, 2, 4 or 8 E1s over PSN with pseudowire emulation.
  • Complies with CESoPSN (RFC 5086), TDMoIP (RFC 5087) & SAToP (RFC 4553) standards.

E1 Timing Options

Clock recovery is a key aspect of E1 transport over PSN due to the variable packet delay in public networks. The Nomus eMux implements Adaptive Clock Recovery (ACR) with an adjustable Jitter Buffer for recovering the E1 clock from the received Packets at the receiving unit. The Jitter Buffer is user programmable up to a depth of 200 msec. Internal & External clock modes are also supported. The clock for each E1 channel can be independently selected.

The E1 Transmit Clock ( towards TDM equipment) options, independently selectable for each channel are:

  • Recovered Clock: The E1 clock recovered from the received encapsulated packets using Adaptive Clock Recovery (ACR) is used as the transmit clock.ACR is based on a Jitter Buffer whose depth is user-programmable up to 200 msecs.
  • Loopback Clock: The clock from the receive E1 signal is used as the transmit source.
  • Internal Clock: A built-in crystal oscillator is used to clock the E1 data.
  • External Clock: An external Clock Source such as a GPS clock is used to provide timing for on of the E1 Ports which is used as the source for all the other ports as well.

E1 Framing Options

The Nomus eMux efficiently transports Unframed, Framed & Fractional E1 as per G.704. It supports CAS signaling transport as well as CRC4 generation & checking.

  • Unframed, Framed & Fractional E1 transport.
  • CAS signaling transport.
  • CRC4 checking & generation.
  • Efficient transport by filtering TS0, HDLC & Idle Time-Slots.
  • Support for Fault propagation.

Serial Data Transport

The Nomus E-Mux transports Serial HDLC data using HDLCoPSN. Efficient transport is supported by filtering of idle patterns.

  • HDLC data transport using HDLCoPSN (RFC 4618).
  • Bandwidth usage efficency witht he filtration of Idle patterns.
  • Support for V.35 with optional support for other interfaces.
  • Internal & External clock source selection.
  • Support for Fault Propagation.

Ethernet Ports

3 Ethernet ports with VLAN support offer versatility to the equipment by with support for fibre or copper Network Ports.

  • 1 Network port which can be FE 100 Base-T or 100 Base-FX.
  • Support for Routing or Switching on network port.
  • 2 FE LAN ports of 100 Base-FX.
  • Support for port-based VLAN Tagging & QoS prioritisation.
  • Transparent packet forwarding or filtering modes.

Traffic Prioritisation

The Nomus eMux prioritises the Encapsulated packets towards the Network using QoS.This enables the delay-sensitive data to reach the destination with minimum delay.

The QoS features supported are:

  • VLAN QoS with 802.1p & 802.1q tagging.
  • IP QoS with Diffserv.
  • EXP marking for MPLS


The Nomus eMux supports varied management options such as a Serial Console, Telnet, Web Browser & SNMP V1/2.

  • Complete OAM function using Console or Ethernet.
  • Loopbacks on E1 Ports for diagnostics.
  • Complete statistics on E1 & Network Ports with Fault History.
  • Network Jitter Buffer monitoring.
  • Telnet, Web & SNMP V1/V2 support.
  • Firmware Download.
  • LEDs for display of E1 Status.