NETGEAR XM128 ISDN - Manual (Page 57)

Reference Guide for the Model XM128 ISDN Digital Modem
ISDN Overview 6-9
If the address-matching process is again unable to tell which protocol to use, the Model XM128
modem goes into the Multi Auto-answering Routine by examining the B channel data pattern and,
hence, determining the protocol to use.
When alerted, the Model XM128 modem sends a RING message to the DTE in the following
format:
RING
FM:17145522863TO:17142630398
Understanding ISDN Communication Protocols
Table 6-5 shows the specifications of different ISDN protocols.
Table 6-5. ISDN protocol specifications
Parameter V.110 V.120 X.75
Layer 1 80 Bits Framing HDLC HDLC
Layer 2 None LAPD LAPB Transparent
Layer 3 None V.120 ISO8208T.70 NL
Error Control No Yes Yes
V.42bis No Yes Yes
Async or Sync if used
with V-Series DTE Async Only Async Only Async Only
Bundle No Yes Yes
Max. Line Speed Async: 38.4 Kbps
Sync: 64 Kbps 64 Kbps
128 Kbps 64 Kbps
128 Kbps
AT-Command
Configuration ATB10 ATB20 ATB00 Transparent
ATB01: T.70 NL