• The LRS-24, "Last Mile" SNMP modem rack, is a 12-slot hub that accommodates any combination of HDSL, copper and fiber modem cards (see Table 1). All cards, electrical or fiber optic, can be managed by the RADview-HPOV or RADview-PC SNMP management system.

• All cards in the hub have remote control abilities for monitoring and/or controlling remote units.

• LRS-24 is available in two different physical hub versions:
  
  ANSI - card insertion, LEDs and switches are at the front, but cable connections are at the rear of the hub. This compact, 4U high unit complies with the American ANSI standard. Cards can be hot-swapped without removing cables.
  
  ETSI - card insertion, LEDs, switches and cable connections are at the front. This version is 30 cm high (almost 6U), and complies with European ETSI standard. Cards can be hot-swapped without removing cables.

• Both Central Management modules, CM-1 and CM-2, have a station clock connection enabling clock distribution to all cards, so that all cards can be synchronized to the same station clock.

• LRS-24 can also be managed from an ASCII terminal. In this case, the CM-1 card can be used for management of modules with SNMP agent on-board, such as HTU-E1C. The CM-2 card supports ASCII terminal management for modules with or without on-board SNMP agents.

POWER SUPPLIES

• LRS-24 can operate with single or dual, AC or DC power supplies. Each power supply supports a full rack of cards. The redundant power supply can be replaced during operation, without affecting the system performance (hot-swapping).

• Cards in the hub can provide remote power feeding for repeaters and remote standalone units. For this purpose, a separate standalone power supply, LRS-PS-FEED, should be ordered (see Ordering).

INSTALLATION AND MAINTENANCE

• All cards can be replaced, or cables removed, during operation, without causing interference to data transmission to/from other cards in the hub.

CENTRALIZED NETWORK MANAGEMENT

• RADview-HPOV management is available for modules with/without integrated SNMP agent, via the SNMP Central Management module (CM-2). The RADview management station is connected to LRS-24 via an integrated Ethernet connection on the CM-2 module. Remote management of the rack is possible using any bridge/router, dial-up or leased line modem, or part of the backbone bandwidth. The CM-2 module provides transparent connection to modules with SNMP agent and acts as a proxy SNMP agent for those cards without an agent.

• The RADview HPOV/UNIX and RADview-PC applications provide network management for LRS-24. RADview manages LRS-24 together with other RAD WAN products such as Megaplex-2100 E1/T1 Multiplexer and DXC DACs products. RADview-HPOV can be integrated into other NMS applications from third party vendors running on the standard HPOV/UNIX platform.
  LRS-24 can also be managed on a PC platform by RADview-PC, a Windows-based Graphical User Interface (GUI) SNMP platform.

• Management functionality is provided in accordance with ITU-T Telecommunication Management Network (TMN) recommendations.

• System management supports real-time monitoring and control of more than 64,000 LRS-24 hubs and connected remote modems at the same time. Several users can simultaneously monitor and control the system.

• The central and remote sites can be managed in real-time. Performance information is available in graph and table format for the last 24 hours. This information can be saved in a file for accounting purposes.

• Telnet support enables terminal connection over any IP network.

• A new software version can be downloaded from a remote site into the CM-2 using X-MODEM protocol. The card can save three different software versions and can switch between them.

• If a major alarm occurs, the LRS-24 CM-2 card can dial through an external dial-up modem to a central management site. This saves a direct connection to remote sites, while providing alerts if critical events occur.

• When the management station includes BootP software, the CM-2 card can automatically retrieve the IP address required for management connection. This saves the need to configure IP addresses for new rack installations.