3Com MSR 50 Series, Руководство по настройке

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2310 C
HAPTER
134: E1
AND
T1 C
ONFIGURATION
Figure 670 Network diagram for an E1/T1 voice system
E1/T1 voice allows the router to provide more channels of voice communication,
greatly improving router utilization and broadening service range.
E1/T1 Interface This section covers these topics:
■
“E1 interface” on page 2310
■
“T1 interface” on page 2311
E1 interface
An E1 interface is logically divided into timeslots (TSs) with TS16 being a signaling
channel.
On E1 interfaces, you may create PRI groups or TS sets.
You may use an E1 interface as an ISDN PRI or CE1 interface.
As an ISDN PRI interface, the E1 interface adopts DSS1 or Q.SIG signaling. Since
TS0 is used to transfer synchronization information and TS16 is used as a D
channel to transfer connection signaling, you may arbitrarily bind any TS other
than TS0 and TS16 into an interface logically equivalent to an ISDN PRI interface.
As a CE1 interface with a signaling channel, the E1 interface can adopt R2
signaling, digital E&M signaling, or digital LGS signaling.
■
When R2 signaling is adopted, every 32 timeslots form a primary frame
(PCM30 for example), where TS0 is used for frame synchronization, TS16 for
digital line signaling, and other 30 timeslots for voice transmission. Every 16
primary frames form one multiframe. In each multiframe, TS0 in even primary
frames conveys frame alignment signal (FAS) and TS0 in odd primary frames
conveys non-FAS (NFAS) about link status information. NFAS provides control
signaling for primary rate multiplexing. In the first primary frame, frame 0, the
high-order four bits in TS16 convey multiframe FAS (MFAS) and the lower-order
four bits convey non-multiframe FAS (NMFAS); TS16 in each of other 15
primary frames conveys line status information for two timeslots. For example,
TS16 in frame 1 conveys the digital line signaling status of TS1 and TS17 while
that in frame 2 conveys the digital line signaling status of TS2 and TS18, and so
on.
■
When digital E&M signaling is adopted, the E1 interface functions as a digital
E&M interface. On the interface, timeslot division and functions are the same
as those with R2 signaling.
Telephone
PSTN PSTN
IP
Gateway
Gateway
Telephone
E1/T1
E1/T1
GK server