Cisco ATA 191 and ATA 192 Analog Telephone Adapter Administration Guide for Multiplatform Firmware - Advanced Options for Phone Services

Publisher

Cisco

URL

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cata/19x/3PCC/english/admin-guide/at9x_b_ata191-192-admin-mp/at9x_b_ata191-192-admin-mp_chapter_01000.html

Published

2026-01-30

Updated

unknown

Accessed

2026-09-24

HTTP status

200

License

Cisco website terms of use; all rights reserved; no-redistribution; short excerpts and locators only

Source notes citing this source

• Cisco's fax troubleshooting for the ATA 191/192 says to verify the fax machine is set to a speed between 7200 and 14400 and to run test faxes in a controlled environment while monitoring network statistics. in context
• On the ATA 191/192, if a T.38 call cannot be set up the call automatically reverts to G.711 fallback. in context
• For fax, Cisco recommends the ATA 191 Multiplatform line use G.711u (USA) or G.711a (elsewhere) as preferred codec with Use pref. codec only set to Yes, and silence suppression and echo cancellation off. in context
• For fax, Cisco recommends setting Network Jitter Level to very high and Jitter Buffer Adjustment to no on the ATA 191 Multiplatform, and disabling call waiting and three-way calling on the fax line. in context
• For fax, Cisco recommends setting FAX Passthru Method to ReINVITE on the ATA 191 Multiplatform line configuration. in context
• Cisco's ATA 191 Multiplatform fax troubleshooting advises confirming fax machine speeds between 7200 and 14400 bps, checking network jitter, loss and delay, and testing between two ATAs in a controlled environment. in context
• The ATA 191/192 Multiplatform guide states that if a T.38 call cannot be set up, the call automatically reverts to G.711 fallback. in context
• Cisco's ATA 191/192 guide advises allocating at least 50 kbps for T.38 fax and approximately 100 kbps for G.711 fallback. in context
• Cisco's ATA 191/192 guide says that when a Cisco media gateway terminates to the PSTN, T.38 fax relay should be disabled and fax enabled via modem passthrough (fax protocol pass-through g711ulaw with fax rate disable) with a T.38 alternative given. in context
• On Cisco ATA 191/192 multiplatform firmware if a T.38 call cannot be set up the call automatically reverts to G.711 fallback. in context
• For fax on Cisco ATA 191 and 192 multiplatform firmware Cisco recommends G.711u (USA) or G.711a (elsewhere) as the preferred codec with silence suppression and echo cancellation disabled. in context

Cite this source record

APA

WarmTransfer. (2026, January 30). Cisco ATA 191 and ATA 192 Analog Telephone Adapter Administration Guide for Multiplatform Firmware - Advanced Options for Phone Services. WarmTransfer. https://warmtransfer.net/knowledge/sources/cisco-ata191-192-mpp-admin-advanced

BibTeX

@misc{warmtransfer-cisco-ata191-192-mpp-admin-advanced,
  title  = {Cisco ATA 191 and ATA 192 Analog Telephone Adapter Administration Guide for Multiplatform Firmware - Advanced Options for Phone Services},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/sources/cisco-ata191-192-mpp-admin-advanced},
  note   = {Cisco, accessed 2026-09-24}
}