SIP User's Manual
A
.
MediaPack
Applications
Version 2.4
147
June 2008
Figure
A-9: Fax Transfer Enabled for IP-to-ISDN (e.g., T.38 Relay)
A.3.1.1 Fax without SIP RE-Invite
The use fax without a SIP RE-Invite transaction (fax autotransition), the user can add T.38
as coder. If T.38 is added a coder it is negotiated in the SDP exchange. If Fax is
successfully negotiated, the system will switch to fax (T.38) without an additional SIP RE-
Invite transaction.
Note: For fax autotransition Fax Signaling Mode must be set to T.38 Relay.
A.3.2 Configuring
Modem Transfer over IP
The general system configuration for call routing is the same as that described in Section
'
1102H1157H
Configuring Fax Transfer over IP
' on page
1103H1158H
144
. For using the Modem Bypass, in the 'IP
Profiles' and 'ISDN Profiles' screens, the parameter ‘Allow Modem Bypass’ must be
enabled, as shown in the figure below:
