Cisco's ATA 191/192 guide advises allocating at least 50 kbps for T.38 fax and approximately 100 kbps for G.711 fallback.

Checked 2026-09-24

Vendor
Cisco
Product
ATA 191
Subsystem
fax optimisation
Deployment
on-premises, multi-tenant
Region
not restricted
Release range
guide revision of 2026-01-30
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). Fax and T.38 in cloud calling: source note fax-t38-ata19x-bandwidth. WarmTransfer. https://warmtransfer.net/knowledge/claims/fax-t38-ata19x-bandwidth

BibTeX

@misc{warmtransfer-claim-fax-t38-ata19x-bandwidth,
  title  = {Fax and T.38 in cloud calling: source note fax-t38-ata19x-bandwidth},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/fax-t38-ata19x-bandwidth},
  note   = {Source note fax-t38-ata19x-bandwidth, checked 2026-09-24}
}

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