Configuring a T3 Mux Board   12

  This chapter describes how to integrate a T3 Mux board with Quad T1 boards on the PortMaster 4. It includes the following sections:

•  "Overview of T3 Mux Boards" on page 12-1
•  "Setting the View" on page 12-1
•  "Mapping T1 Lines to T3 Channels" on page 12-2
•  "Setting the Clock Source" on page 12-2
•  "Performing Diagnostics" on page 12-3

  See the PortMaster 4 Command Line Reference for more detailed command descriptions and instructions.

  You can also configure the PortMaster 4 using the PMVision application for Microsoft Windows, UNIX, and other platforms supporting the Java Virtual Machine (JVM). PMVision replaces the PMConsole interface to ComOS.

       Overview of T3 Mux Boards

  The T3 Mux board demultiplexes DS-3 signals into 28 individual DS-1 signals (also called channels), and terminates those channels on one or more Quad T1 boards. T3 Mux board configuration is primarily a matter of mapping the individual T1 lines of the installed Quad T1 boards to the 28 DS-1 channels of the T3 line. To fully demultiplex a T3 line, you must have seven Quad T1 boards installed in the PortMaster 4.

  The T3 Mux board supports the M13 framing format and converts bipolar 3-zero substitution (B3ZS) line encoding to nonreturn to zero (NRZ) DS-3 signaling. A T3 Mux board can provide internal clocking or can receive clocking externally at a rate of 44.736Mbps. The DS-1 clocking rate is 1.544Mbps.

  You can install a T3 Mux board in any slot except slot 4, which is reserved for the manager module. T3 Mux boards do not become active until you configure an IP address for the PortMaster 4.

       Setting the View

  Before configuring a T3 Mux board and any Quad T1 board that it demultiplexes, you must set the view to the slot containing the appropriate board. Enter the show boards  command to determine the identification number for the board. The board identification number is the same as the number of the slot in which the T1 line is installed.

  Command> show boards

  Use the following command to set the view to a slot with an installed T1 board:

  Command> set view Slotnumber

       Mapping T1 Lines to T3 Channels

  You can configure the lines on a Quad T1 board to use their physical ports (Line0 through Line3), or map them to DS-1 channels on the T3 line. To map the termination of a T1 line, you must first set the view to the slot with the installed Quad T1 board.

  Command> set view Slotnumber

  You can now use the set  Line0 source command to map the T1 line source. Use the local  keyword to terminate the line at its own RJ-45 port--this is the default. Or you can specify the slot number and channel of the T3 Mux board to multiplex the T1 line to a T3 channel between 1 and 28. For example, to map Line0 on a Quad T1 board in slot 2 to DS-1 channel 25 of the T3 line of a T3 Mux board installed in slot 8, enter the following commands:

  Command> set view 2
Command 2> set line0 source 8:25

  Note ¯ Before configuring the T3 Mux board, you must activate it by assigning an IP address to Ether0 or Ether1.

       Setting the Clock Source

  You can set clocking on a T3 Mux board in several ways. This section discusses the options for setting the clock source.

       Setting the Clock Source for Each Synchronous Serial Line

  To set a clock source for the T1 lines, you must first set the view to a slot with the installed Quad T1 board.

  Command> set view Slotnumber

  You can now use the set  Line0 clock  command to set the clock source. You use the backplane  keyword of this command to derive clocking from a T3 Mux board. If you want the internal T1 clock to supply clocking, use the internal  keyword. Use the external  keyword if you need an external clock source.

  For example, to specify the backplane as the clock source for Line0 on a Quad T1 board installed in slot 1, enter the following command:

  Command 1> set line0 clock backplane

  Warning ¯ Do not set a T1 line to internal  if another active line on the same Quad T1 board is set to external  or backplane .

  If you want to derive clocking from the backplane, you must enable the T3 Mux board to provide clocking to the backplane.

       Enabling Clocking on the Backplane

  When you configure a T3 Mux board to provide clocking to the PortMaster 4 backplane, other boards can derive their clocking from the backplane. To set the T3 Mux board to provide clocking to the backplane, you must first set the view to the slot with the installed T3 Mux board. For a T3 Mux board installed in slot 1, for example, you enter the following command:

  Command> set view 1

  You can now use the following command to set the T3 Mux board to provide clocking to the backplane:

  Command 1> set mux backplane-clock enable|disable

       Setting T3 Mux Clocking

  You can set a T3 Mux board to either provide clocking to the T3 line or obtain clocking from the T3 line.

  You use the external  keyword to specify that the T3 Mux board obtain clocking from the T3 line. When you use the internal  keyword, the T3 Mux board provides clocking for the T3 line. To set T3 Mux clocking, you must first set the view to the slot with the installed T3 Mux board. For a T3 Mux board installed in slot 1, for example, you enter the following command:

  Command 1> set view 1

  You can now use the following command to set T3 Mux clocking:

  Command 1> set mux line-clock external|internal

       Performing Diagnostics

  This section describes how to enable a PortMaster 4 to conduct loopback tests on a single DS-1 channel and on a T3 line.

       Looping an Individual DS-1 Channel

  To use the following command to perform diagnostic loopback tests on a single DS-1 channel within a T3 line, you must first set the view to the slot with the installed T3 Mux board. For a T3 Mux board installed in slot 1, for example, enter the following command:

  Command> set view 1

  You then enter the following command to enable the PortMaster to perform loopback tests on a single DS-1 channel:

  Command 1> set mux channel-loop Channel auto|on|off

       Looping the T3 Line

  To use the following command to diagnose a T3 line, you must first set the view to the slot with the installed T3 Mux board. For a T3 Mux board installed in slot 1, for example, enter the following command:

  Command> set view 1

  You can then use the following command as a diagnostic to loop the T3 line:

  Command 1> set mux line-loop auto|on|off