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  • The IP-LLA provides 2 or 4 wire analogue, and low, medium bit rate lease line services over IP/Ethernet
  • The internal PPP gateway function allows the IP-LLA to transport all analogue, serial interfaces and Ethernet over the IP/Ethernet network.
  • IP-LLA facilitates the replacement of point-to-point private circuits (BT EPS PWs Kilostream) using the unique Point-to point tunnel function across IP networks.


To support legacy services transported over traditional analogue Private Circuits for voice band modems for SCADA. RTUs PLA etc, the IP-LLA allows migration of the legacy interfaces over 21CN IP networks.

The IP-LLA offers the following interfaces:

  • 2-wire / 4 wire analogue interface for lease line modems or voice links using 300-3400Hz. Modem speeds up to 14.4Kbps 4wire
  • RS232 (V24/V28) or RS485 asynchronous serial data transmission interface upto 115Kbps
  • 4 digital I/O interfaces for remote signalling acquisition and volt free relay contacts
Not available

Point-to point Tunnel and Communication Server modes
Low speed serial links and analogue links can be migrated to IP using the IPLLA's Tunnel function offering secure communications when used with a router supporting IPsec tunnelling. The IP-LLA can be locally or remotely managed using Telnet from any other IP-LLA on the network. From the WAN, LAN or internet access, remote access is available for the serial ports, analogue and modem interfaces, and digital I/O. Using optional communication port emulator software non-IP applications can be supported on the IP-LLA.

PPP Gateway and Asynchronous/Synchronous converter functions
The IP-LLA can be used where no IP/Ethernet network is available to the remote end. The built in PPP gateway function allows a synchronous or asynchronous link to set up the PPP connection that will transport all the IP-LLA interfaces including Ethernet interface.


  • Transport over IP/Ethernet of the 2-wire or 4-wire analog LL (embedded G.711 A and μ law codec)
  • Transport over IP/Ethernet of the low and medium bitrate LL
  • Transport over IP/Ethernet of the digital I/O PPP gateway to transport over serial link all the interfaces including Ethernet
  • Communication port server
  • Digital I/O server
  • SNMP proxy for the digital I/O, serial links and LLA link
  • Asynchronous


Network access:

  • 1 Ethernet 10/100Base-T port - RJ45

User ports:

  • 1 2-wire or 4-wire analog port (300-3400 Hz / 600 Ω) -RJ45
  • 1 asynchronous RS232 or RS485 port - RJ45
  • 1 asynchronous RS232
  • RS422 port - DB25M
  • 4 remote signalling acquisition ports (digital input 2-pole dry contact) - RJ45
  • 4 remote relay control ports (digital output 2-pole dry contact) - RJ45

IP Protocols


Mechanical data

  • Desktop, wall mountable metal housing
  • Dimensions: 218(W) x 48(H) x 128(D) mm - Weight: 1.0 kg

Power requirements

  • External power adapter, Input 12 Volt DC @ 1 A


  • Local and remote web-based management using HTTP
  • Configuration using SNMP V1
  • Supervision using SNMP V1 TRAP
  • Software update using FTP

LED indications

  • Power, Alarm, Ethernet, LLA
  • RS232 or RS485, On/Data
  • RS232 or RS422, On/Data
  • Digital Input (x4), Digital output (x4)

Conformity to International Standards

CE Mark

  • Safety: EN 60950 compliant
  • Electromagnetic radiation: EN 55022 compliant
  • Immunity: EN 55024 compliant

Environmental conditions

  • Storage temperature: -25C +55C (-13F to 131F)
  • Transportation temperature: -40C to +70C (-40F to 158F)
  • Operating temperature: -5C to +45C (23F to 113F) ETS 300 019-2-3 Class 3.2 compliant
  • Railway Approved EN50121-4

Power supply

  • External mains adapter 200 to 240 VAC (included)

National Rail Product Approved: PA05/05819

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