Any SIP or H.323 fixup/ALG function on the NAT firewall in front of the Expressway-E should be disabled because it interferes with Expressway operation.

Checked 2026-09-25

Vendor
Cisco
Product
Cisco Expressway
Subsystem
firewall
Deployment
on-premises
Region
not restricted
Release range
X14.0 onward
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Setting up business-to-business calling on Cisco Expressway: source note expressway-b2b-setup-disable-alg. WarmTransfer. https://warmtransfer.net/knowledge/claims/expressway-b2b-setup-disable-alg

BibTeX

@misc{warmtransfer-claim-expressway-b2b-setup-disable-alg,
  title  = {Setting up business-to-business calling on Cisco Expressway: source note expressway-b2b-setup-disable-alg},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/expressway-b2b-setup-disable-alg},
  note   = {Source note expressway-b2b-setup-disable-alg, checked 2026-09-25}
}

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