3com 3031 Instruccion De Instalación

Generally, a CE1/PRI interface is applied to the leased line and dial-up services. For 
the sake of simplicity, this part will not cover its typical configuration and fault 
diagnosis, but you can find them in the relevant sections in Parts IV “Link Layer 
Protocol” and Part XIII “Dial-up”.

This section describes how to configure an E1-F interface.

E1-F interface is fractional E1 interface, and it is respectively simplified CE1/PRI 
interface. If there is no need to use multiple channel sets or if ISDN PRI is not 
necessary in an E1 application, it is too much to use CE1/PRI interface. At this time, 
E1-F interface is more than enough for meeting the simple E1 access 
requirements. Compared with CE1/PRI interface, E1-F interface is a nice low-cost 
choice for E1 access.

Compared with CE1/PRI interfaces, E1-F interface has the following features:

■

When working in framed mode, E1-F interface can only bind time slots into 
one channel set, but CE1/PRI interface can group timeslots randomly and bind 
them into multiple channel sets.

■

E1-F interface does not support PRI operating mode.

■

E1-F interface can work in both framed and unframed modes.

When it works in unframed mode, it is a non-timeslot interface of 2048kbps data 
bandwidth. In this case, it is logically equivalent to a synchronous serial interface, 
supporting the data link layer protocols PPP, HDLC, Frame Relay, LAPB and X.25, as 
well as the network protocols IP and IPX.

When it works in framed mode, however, it is physically divided into 32 time slots 
numbered in the range of 0 to 31. In these time slots, except for time slot 0 used 
for synchronization information transmission, all the other time slots can be 
randomly bound into one channel set. E1-F interface has the rate of nx64kbps, 
owns logical features of synchronous serial interface, and supports the data link 
layer protocols PPP, Frame Relay, LAPB and X.25 as well as the network protocols IP 
and IPX.

E1-F interface configuration includes:

■

Enter the view of a specified interface

■

Set interface operating mode

■

Set interface rate after binding operation

■

Set line code format

■

Set line clock

Table 191   Displaying and debugging the CT1/PRI interface information

Display the operating state of 
CT1/PRI interface

 

Display the operating state of 
channel-set or pri-set