Cisco WRP400-G1 Administration Guide - Page 41

Configuring Voice Services Optimizing Fax Completion Rates 3 Optimizing Fax Completion Rates Issues can occur with fax transmissions over IP networks, even with the T.38 standard, which is supported by the WRP400. You can adjust several settings on your WRP400 to optimize your fax completion rates. NOTE Only T.38 Fax is supported. The WRP400 supports one connection. STEP 1 Ensure that you have enough bandwidth for the uplink and the downlink. • For G.711 fallback, it is recommend to have approximately 100Kbps. • For T.38, allocate at least 50 kbps. STEP 2 To optimize G.711 fallback fax completion rates, set the following on the Line tab of your ATA device: • Network Jitter Buffer: very high • Jitter buffer adjustment: disable • Call Waiting: no • 3 Way Calling: no • Echo Canceller: no • Silence suppression: no • Preferred Codec: G.711 • Use pref. codec only: yes STEP 3 If you are using a Cisco media gateway for PSTN termination, disable T.38 (fax relay) and enable fax using modem passthrough. For example: modem passthrough nse payload-type 110 codec g711ulaw fax rate disable fax protocol pass-through g711ulaw STEP 4 Enable T.38 fax on the WRP400 by configuring the following parameter on the Line tab for the FXS port to which the FAX machine is connected: FAX_Passthru_Method: ReINVITE Cisco Small Business WRP400 Administration Guide 39