2Mbps DSL Modems

Ascom AM2048-CAP DSL Modem
The AM2048-CAP DSL modem has the technology to deliver full duplex transmission at 2Mbps over 2 or 4 wire twisted pair cable. The AM2048 DSL modem sets new standards in the distance available at 2Mbps using DSL technology. Fractional 2Mbps, clear channel 2Mbps or n x 64kbps are provided in this latest product in the DSL range from Ascom.
Click here for a configuration guide
New Ethernet 10BaseT Bridge / Router Module now available

Features of the AM2048 DSL modem
  • Multiple interface options (X.21, V.35, G.703, 10BaseT, USB)
  • Latest DSL technology.
  • Data rates of n x 64Kbps to 2048Kbps.
  • 2/4 wire technology.
  • Remote configuration.
  • Extensive self test features.
  • Stand alone or rack mountable.

AM2048 DSL modem

 

Configuration of the AM2048-CAP
Assumptions
The AM2048-CAP 2Mbps DSL modem is designed to function at n x 64Kbps speeds up to 2048Kbps using either a 2 or 4 wire circuit. For the following configuration these assumptions have been made :-
  • A 4 wire circuit is being used
  • The user interface is X.21
  • Line Rate of 2048Kbps
  • Data Rate of 2048Kbps
Getting Started
It is probably best to configure the modems 'back to back' first of all, then once the configuration has been successfully achieved the 2 modems can be introduced into a live scenario. To connect the modems 'back to back' one of the line leads that is shipped with the modems can be used. Plug this cable into the port marked 'line' on each modem and power the units on.
Configuration
Configuration of the AM2048-CAP is carried out by using a VT-100 terminal (or similar emulation program) connected to the units DB-9 management port using the supplied management cable. It must be noted that only one modem has to be configured, this modem shall be designated as the 'Master' modem and the master modem can pass all configuration information to the 'Slave' modem via an embedded operations channel (EOC) contained in the DSL link.
Terminal Settings
  • Baud Rate = 19200
  • Data Bits = 8
  • Stop Bit = 1
  • Parity = None
  • Handshaking = XON / XOFF
Step 1 - Accessing the Management Software
Once the correct terminal settings are entered, the following screen should appear. To enter the top level menu of the management software carry out the following :-
  • Press 'SPACE BAR' - Login prompt should appear
  • Press the character 'C' to enter the configuration mode and 'RETURN'
  • Enter the default password and 'RETURN'
  • Press 'RETURN' once more
AM2048-CAP Login Screen


Step 2 - Designate the modem to be a 'Master'
The top level menu should now be visible. The next step is to designate this modem to be the 'Master'. The Master modem controls timing across the DSL circuit as well as providing the slave modem with its configuration information.
AM2048-CAP Top Level Menu
  • Press the character 'C' to enter configuration options.
AM2048-CAP Configuration Menu
  • Press the character 'M' to enter Master / Slave options.
AM2048-CAP Master / Slave Menu
From the above screen the modem can be set to 'Master' and also the number of lines and the DSL speed can be defined. To cycle through the parameters use the 'TAB' key, to select a parameter use the 'SPACE BAR'.
  • Use the 'TAB' key to cycle through to the "Master - ELU" field.
  • Press the 'SPACE BAR' to highlight the "Master - ELU" field.
Using the 'TAB' and 'SPACE BAR' the following fields also need to be highlighted.
  • Point to Point
  • 2 Lines
  • 1024Kbps per Line.
  • Maximum Power must not be set when using a private circuit.
Once all the correct fields have been set, issue a 'RETURN'. The modem will then reboot and return to the login screen.
Step 3 - Setting the User Data Rate
Once the modem has been set to 'Master' and rebooted the login screen will appear as shown in step 1. Repeat the login sequence until the top level menu is reached.
  • From the top level menu press 'C' to enter the configuration menu
  • From the configuration menu press 'U' to enter the user port menu
From this screen (shown below) all parameters associated with the User interface can be accessed and configured. In this instance the user interface is X.21. The speed of this user interface can be selected in increments of 64Kbps up to 2048Kbps. There are 32 increments and the factory default is 6 (6 x 64 = 384Kbps).
  • Press 'TAB' until the "Nx64" field is highlighted
  • Enter '32' into this field
  • All other fields should be untouched
  • Issue a 'RETURN'
AM2048-CAP User Port Configuration
The configuration is now complete. The modems will now go through a process of 'Sync-ing up' this may take a minute or 2. When the modems have 'Sync-ed' they are ready to communicate. To check that the modems are 'Sync-ed' the only LED's that should be illuminated on the front panel should be the 'Power' and 'Master' (On the master modem). Further confirmation of the modem's alarm status can be viewed in the alarm / status menu from the top level menu. For normal operation (with X.21 interface) all the alarms should be 'off'.
The modems may now be introduced to a circuit. It is advisable for the Master modem to be located at a central site or where access can be gained in case any further configuration or interrogation needs to be carried out.

 

Ethernet bridge / router module for DSL modems

  • No need for separate Routers
  • Direct Ethernet 10BaseT connection
  • Compatible with AM128E, AM512, AM1024 & AM2048-CAP
  • Simple configuration
  • Supports IP and IPX
  • Static Routing and RIP
  • NAT Supported

ABR bridge / router module


The new bridge router module is the latest module to be released for the AM series of DSL modems. The module lets you directly connect DSL modems to your LAN without the need for a separate bridge or router.

Remote management via Telnet is supported as well as a VT100 terminal connection for local management. Comprehensive statistics can be monitored allowing network managers to ensure a high quality of service.

Specifications
Interfaces
  • Ethernet - 10BaseT (and USB for the AM2048-CAP)
Data Rates
  • 64 to 2048Kbps
LED's
  • Li - Link Integrity, Rx & Tx - Receive & Transmit
Ethernet
    Handling of the following Frame types over CSMA/CD
  • Ethernet II
  • SNAP
  • IEEE 802.2
  • IEEE 802.3
IP Routing
  • Address Resolution Protocol (ARP)
  • Internet Protocol (IP - RFCs: 760, 791, 815)
  • Internet Control Message Protocol (ICMP)
  • Routing Information Protocol (RIP)
  • RIP II - Run in RIP 1 compatibility mode
  • Static Initialisation of Routing Entries
IPX Routing
  • Internetwork Packet Exchange (IPX) including Propagated NetBIOS IPX type 20 frames
  • Routing Information Protocol (RIP)
  • Service Advertising Protocol (SAP)
  • Static initialisation of RIP and SAP routing tables
  • Auto learning of local Network Numbers and Types
WAN Services
  • Point-to-Point Protocol (PPP - RFCs: 1661,1662) is run over all WAN Links
  • The following extensions to PPP are also supported
  • PPP Authentication (PAP - RFC: 1334)
  • PPP Control Protocol (IPCP - RFC: 1332) -includes support for Van Jacobson Header Compression, and both numbered and unnumbered links
  • User Datagram Protocol (UDP - RFC-.768)
  • Transmission control Protocol (TCP - RFCs: 675, 761, 793)
  • Using Telnet Protocol (TELNET - RFCs: 854. 855)
  • SYSLOG system logging performed on UDP port 514
Other
  • Distribution of Network time using Simple Network Time Protocol (SNTP RFC: 2030)
  • Network Address Translation (NAT) - based on ideas in RFCs 1631 and 1919