3com MSR 20-20 참조 매뉴얼

Loopback is intended for checking the condition of interfaces or cables. Disable it 
otherwise.

n

# Set T1-F interface Serial 2/0 in local loopback mode.

<Sysname> system-view

[Sysname] interface serial 2/0

[Sysname-Serial2/0]ft1 loopback local 

ft1 timeslot-list list [ speed { 56k | 64k } ]

T1-F interface view

list: Specifies timeslots to be bundled. They are numbered 1 through 31. You may 
specify a single timeslot by specifying its number, a range of timeslots by 
specifying a range in the form of number1-number2, or several discrete timeslots 
by specifying number1, number2-number3.

speed { 56k | 64k }: Time slot bundling speed in kbps. If 56k applies, timeslots are 
bundled into an N 

× 56 kbps bundle. If 64k (the default) applies, timeslots are 

bundled into an N 

× 64 kbps bundle.

Use the ft1 timeslot-list command to bundle timeslots on a T1-F interface.

Use the undo ft1 timeslot-list command to restore the default.

By default, all the timeslots on the T1-F interface are bundled to form a 1536 kbps 
interface.

Timeslot bundling results in interface rate change. For example, after you bundle 
timeslots 1 through 10 on the interface, the interface rate becomes 10 

× 64 kbps 

or 10 

× 56 kbps.

Only one channel set can be created on a T1-F interface, and this channel set is 
associated with the current synchronous serial interface. On a CT1/PRI interface, 
however, you may create multiple channel sets; for each of them, the system 
automatically creates a synchronous serial interface.

# Bundle timeslots 1, 2, 5, 10 through 15, and 18 on T1-F interface Serial 2/0.

<Sysname> system-view

[Sysname] interface serial 2/0

[Sysname-Serial2/0] ft1 timeslot-list 1,2,5,10-15,18