R0106-HP MSR Router Series Voice Configuration Guide(V7)

138
Configuring fax over IP
Fax over IP (FoIP) transmits and receives faxes over the Internet.
Figure 57 FoIP network diagram
Fax transmission flow
Fax transmission operates in the following phases:
1. Call establishment—The calling terminal sends a Calling Tone (CNG) to identify itself as a fax
machine. The called terminal sends a Called Station Identifier (CED) tone to identify itself as a fax
machine.
2. Pre-message procedure—The calling or called terminals identify and negotiate the fax capabilities,
including the modulation speed.
3. In-message procedure—The calling terminal transmits fax packets in accordance with the T.4
procedure, and packet transmission control functions are performed (including packets
synchronization, error detection and correction, and line monitoring).
4. Post-message procedure—The calling or called terminal performs the control operations such as
end-of-message signaling, confirmation signaling, and multipage signaling.
5. Call release—Either the calling or called terminal disconnects the call.
FoIP configuration task list
Tasks at a
g
lance
Configuring the fax protocol:
• (Required.) Configuring the standard T.38 protocol
• (Optional.) Enabling CNG fax switchover
• (Optional.) Enabling ECM
• (Optional.) Configuring an NSF code for nonstandard capabilities negotiation
• (Required.) Configuring the maximum fax rate for rate training
• (Required.) Configuring a rate training mode
• (Required.) Adjusting the transmit energy level
(Required.) Configuring fax pass-through
PSTN
PSTN
Internet
Fax Fax