You can configure a channelized T3 interface to send MDL messages.
MDL messages are supported only when T3 framing uses C-bit parity,
the default setting.
To configure a channelized T3 interface to send
MDL messages:
Specify a T3 interface.
host1(config)#controller t3 8/0
(Optional) Configure the interface to operate in an MDL
carrier environment.
host1(config-controll)#mdl carrier
Specify the MDL messages.
host1(config-controll)#mdl string eic "ERX-1410"
host1(config-controll)#mdl string fic "FG786"
host1(config-controll)#mdl string lic "Bldg
10"
host1(config-controll)#mdl string pfi "Site
25"
host1(config-controll)#mdl string port 0800
host1(config-controll)#mdl string unit 080001
Enable transmission of MDL messages.
host1(config-controll)#mdl transmit path-id
host1(config-controll)#mdl transmit idle-signal
host1(config-controll)#mdl transmit test-signal
mdl carrier
Use to specify that an interface is used in the carrier
environment.
Example
host1(config-controll)#mdl carrier
Use the no version to restore
the default situation, in which the interface does not operate in
the carrier environment.
The following configuration tasks are optional
when you configure a T3 controller:
Specify a cable length.
Change the clock source.
Change the framing format.
Enable or disable SNMP link status processing.
Assign a text description or an alias to the interface.
cablelength
Use to adjust the transmit power appropriate to the length
of the T3 cable.
Specify a cable length in the range 1–450 feet.
The router supports two transmit powers, one for a cable
length 1–225 feet and another for a cable length 226–450
feet. Therefore, it is not necessary for you to know the exact length
of your cable. You only need to know if the cable length is greater
than 225 feet. For example, if your cable size exceeds 225 feet, specify
any number greater than 225 (and less than 451).
Example
host1(config-controll)#cablelength 300
Use the no version to restore
the default value, 0 feet.
From Global Configuration mode, specify the T3 controller
in slot 0, port 1.
host1(config)#controller t3 0/1
Assign a range of timeslots to a channel and subchannel.
For example, assign the following range of timeslots:
1, 3–8, and 10 to channel 2, subchannel 1. Timeslots 2, 9, and
11–24 are available for other subchannels.
host1(config-controll)#t1 2/1 timeslots 1,3-8,10
Optional Tasks
The T1 channel configuration commands enable you
to specify options for a single channel, multiple individual channels,
ranges of channels, or any combination of the three types of specifications.
For example:
host1(config-controll)#t1 2,4,6-15,20-25 clock
source line
The following configuration tasks are optional
when you configure T1 channels:
Disable T1 channels.
Change the clock source.
Assign a text description or an alias to the interface.
Change the framing format.
Enable or disable SNMP link status processing.
Configure FDL messages.
controller t3
Use to specify a T3 controller in slot/port format.
slot—Number of the slot in
which the line module resides in the chassis
Use to configure the transmit clock source for T1 channels.
The router supports internal and line clocking.
If you specify internal clocking, the interface transmits
data using the line module or the chassis as the internal clock. You
must specify one of the following for internal clocking:
module—Specifies internal
clock is from the line module itself
chassis—Specifies internal
clock is from the configured router clock
If you specify line clocking, the interface transmits
data with a clock recovered from the line’s receive data stream.
Example
host1(config-controll)#t1 2,4-10 clock source
line
Use the no version to restore the default value, line.
Use to specify an FDL message as defined in the ANSI T1.403
specification.
Note:
The router sends these FDL messages only if you have issued
the t1 fdl command with the ansi or all keyword and then issued the t1 fdl transmit command.
Use to configure the router to send the specified type
of FDL message.
By default, the router sends only FDL performance data
messages.
Note:
The router sends FDL messages specified with t1 fdl string only if you have issued the t1 fdl command with the ansi or all keyword. If
you specified the att keyword with the t1 fdl command, the router
sends only performance data.
Specify the keyword path-id to transmit path identifications every second.
Specify the keyword idle-signal to send idle signals every second.
Specify the keyword test-signal to transmit test signals every second.
Example
host1(config-controll)#t1 28 fdl transmit
path-id
Use the no version to disable
transmission of the specified FDL message or all FDL messages.
You must configure an HDLC channel for each group
of fractional T1 lines and each full T1 line.
To configure an HDLC channel, specify a serial
interface (for example, HDLC channel in slot 0, port 1, channel 1,
subchannel 5).
host1(config)#interface serial 0/1:1/5
Optional Tasks
The following configuration tasks are optional
when you configure an HDLC channel on a channelized T3 interface:
Configure the CRC.
Specify the HDLC idle character.
Enable data inversion on the interface.
Set the time interval for monitoring bit and packet rates.
Set the MRU.
Set the MTU.
Assign a text description or an alias to the serial interface.
crc
Use to configure the size of the CRC.
The CRC is an error-checking technique that uses a calculated
numeric value to detect errors in transmitted data.
16 and 32 indicate the number of bits per frame that are
used to calculate the frame check sequence (FCS). Both the sender
and receiver must use the same setting.
Use a 32-bit CRC when transmitting long streams at fast
rates and to provide better ongoing error detection.
Example
host1(config-if)#crc 32
Use the no version to restore
the default value, 16.
You should coordinate this value with the network administrator
on the other end of the line.
If you configure a different MRU value in higher-level
protocols, such as IP, the router uses the lower value. This can produce
unexpected behavior in your network.
Example
host1(config-if)#mru 1600
Use the no version to restore
the default, 1600 bytes.
You should coordinate this value with the network administrator
on the other end of the line.
If you configure a different MTU value in higher-level
protocols, such as IP, the router uses the lower value. This can produce
unexpected behavior in your network.
Example
host1(config-if)#mtu 1600
Use the no version to restore
the default, 1600 bytes.
