T1 and E1 Controllers
Cisco controllers negotiate the following parameters between an access server and a central office: line coding, framing, clocking, DS0/time slot provisioning, and signalling.
Time slots are provisioned to meet the needs of particular network scenarios. T1 controllers have
24 time slots, and E1 controllers have 30 time slots. To support traffic flow for one ISDN PRI line in a T1 configuration, use the pri-group command. To support traffic flow for analog calls over a channelized E1 line with recEive and transMit (E&M -- also ear and mouth) signalling, use the cas-group 1 timeslots 1-30 type e&m-fgb command. Most telephone companies do not support provisioning one trunk for different combinations of time slot services, though this provisioning is supported on Cisco controllers. On a T1 controller for example, time slots 1 to 10 could run PRI, time slots 11 to 20 could run channel-associated signalling (CAS), and time slots 21 to 24 could support leased-line grouping.
The following example configures one of four T1 controllers on a Cisco AS5300 access server:
as5300# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
as5300(config)# controller t1 ?
<0-3> Controller unit number
as5300(config)# controller t1 0
as5300(config-controller)# framing esf
as5300(config-controller)# linecode b8zs
as5300(config-controller)# clock source line primary
as5300(config-controller)# pri-group timeslots 1-24
as5300(config-controller)#
This example supports modem calls and circuit-switched digital calls over ISDN PRI.
Non-ISDN Channelized T1 and Channelized E1 Lines
A channelized T1 or channelized E1 line is an analog line that was originally intended to support analog voice calls, but has evolved to support analog data calls. ISDN is not sent across channelized T1 or E1 lines. Channelized T1 and channelized E1 lines are often referred to as CT1 and CE1. These channelized lines are found in "old world," non-ISDN telephone networks.
The difference between traditional channelized lines (analog) and nonchannelized lines (ISDN) is that channelized lines have no built-in D channel. That is, all 24 channels on a T1 line only carry data. The signalling is in-band or associated to the data channels. Traditional channelized lines do not support digitized data calls (for example, BRI with 2B + D). Channelized lines support a variety of in-band signal types, such as ground start, loop start, wink start, immediate start, E&M, and R2.
Signalling for channelized lines is configured with the cas-group controller configuration command. The following example configures E&M group B signalling on a T1 controller:
as5300# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
as5300(config)# controller t1 0
as5300(config-controller)# cas-group 1 timeslots 1-24 type ?
e&m-fgb E & M Type II FGB
e&m-fgd E & M Type II FGD
e&m-immediate-start E & M Immediate Start
fxs-ground-start FXS Ground Start
fxs-loop-start FXS Loop Start
r1-modified R1 Modified
sas-ground-start SAS Ground Start
sas-loop-start SAS Loop Start
as5300(config-controller)# cas-group 1 timeslots 1-24 type e&m-fgb
as5300(config-controller)# framing esf
as5300(config-controller)# clock source line primary
as5300(config-controller)#
Try:
http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_configuration_guide_chapter09186a00800ca656.html#wp1001208
