363-206-295
Technical Specifications
10-32
Issue 1
December 1997
At the packet layer, DDM-2000 OC-12 Multiplexers are configured as a passive DTE with
the following parameters as shown in Table 10-17.
At the link layer, the DDM-2000 OC-12 Multiplexer uses the standard LAPB protocol with
the following parameters as shown in Table 10-18.
DDM-2000 OC-12 Multiplexers use synchronous, full duplex, and continuous carrier
communication. Data rates of 1200, 2400, 4800, 9600, and 19200 are supported. The
EIA-232-D interfaces is configured as DTE, using the pin connections specified in
Table 10-19.
Table 10-19. TL1/X.25 Interface - EIA-232-D Pin Connections
Table 10-17. TL1/X.25 Interface — X.25 Packet Layer Parameters
Parameter
Value
Packet Size
Window Size
D bit support
M bit support
128 bytes or 256 bytes
2 packets
NO
YES
Table 10-18. TL1/X.25 Interface — LAPB Link Layer Parameters
Parameter
Value
Maximum Frame
Size
Modulo
Window Size
n2
T1
T3
2104 bits
8
7 frames
7 retires
3 seconds
20 seconds
Pin
Description
2
3
4
5
6
7
8
15
17
20
Transmitted Data
Received Data
Request to Send
Clear to Send
DCE Ready
Signal Ground
Received Line Signal Detector
Transmitted Signal Element Timing (DCE to DTE)
Receiver Signal Element Timing (DCE to DTE
DTE Ready*
*
DTE is always on when system is powered.
