ZyXEL Communications omni series Benutzerhandbuch
30 ISDN Communication Basics
•
V.110
•
X.75
or the call may be initiated by an analog device (non-data).
This section will provide some general guidelines for setting up the
device for call answer handling. Be aware that the TA will not
automatically answer a call unless S-register S0 is set to a value
greater than 0 (zero). If S-register S0=0, the TA will only report
“RING” to your terminal program. It can also respond with an
audible tone (external) that will allow you to decide whether or not
you should take any action.
device for call answer handling. Be aware that the TA will not
automatically answer a call unless S-register S0 is set to a value
greater than 0 (zero). If S-register S0=0, the TA will only report
“RING” to your terminal program. It can also respond with an
audible tone (external) that will allow you to decide whether or not
you should take any action.
When an ISDN data call comes in, the TA will try to negotiate a
connection using the proper ISDN protocol.
connection using the proper ISDN protocol.
When an analog call comes in, the TA will send the call to the analog
port as the factory default, Phone 1 and then Phone 2 (non-data).
port as the factory default, Phone 1 and then Phone 2 (non-data).
Digital Data
The omni currently supports Circuit Switched Data (CSD) for ISDN
data applications. The CSD protocols supported by the TA include:
PPP, MPPP, V.120, X.75, and V.110. PPP is the most popular
protocol used in North America; it is used by most Internet service
providers. Once the TA answers a call, it will examine the incoming
data to determine which protocol to use, and automatically switch to
this mode. The TA is able to auto-switch for PPP, MPPP, V.120,
X.75, V.110, and above protocols over the speech channel. In most
cases, you can rely on the auto-switching feature for your
applications. If you need more specific settings for answering calls,
refer to the section entitled “Answering a Call using MSN” found
later in this chapter.
data applications. The CSD protocols supported by the TA include:
PPP, MPPP, V.120, X.75, and V.110. PPP is the most popular
protocol used in North America; it is used by most Internet service
providers. Once the TA answers a call, it will examine the incoming
data to determine which protocol to use, and automatically switch to
this mode. The TA is able to auto-switch for PPP, MPPP, V.120,
X.75, V.110, and above protocols over the speech channel. In most
cases, you can rely on the auto-switching feature for your
applications. If you need more specific settings for answering calls,
refer to the section entitled “Answering a Call using MSN” found
later in this chapter.
Determining the Packet Length
The user’s information is sent on a frame-by-frame basis for V.120
and X.75. Sometimes we call it “packetized.” The maximum frame
length on the sending side should not exceed the maximum frame
and X.75. Sometimes we call it “packetized.” The maximum frame
length on the sending side should not exceed the maximum frame