Cisco lists 14 TLS cipher suites supported for secure SIP in Webex Calling, of which TLS_AES_256_GCM_SHA384 is the only one at 256 bits and the remaining 13 are AES-128 suites spanning the TLS 1.3 AES_128_GCM form and the ECDHE ECDH and DHE key exchanges in GCM and CBC modes.

Checked 2026-09-16

Vendor
Cisco
Product
Webex Calling
Subsystem
transport security
Deployment
not restricted
Region
not restricted
Release range
not restricted
Checked
2026-09-16

Sources

Cite this note

APA

WarmTransfer. (2026, September 16). TLS certificates and secure SIP failures: source note siptls-fourteen-ciphers-one-at-256-bits. WarmTransfer. https://warmtransfer.net/knowledge/claims/siptls-fourteen-ciphers-one-at-256-bits

BibTeX

@misc{warmtransfer-claim-siptls-fourteen-ciphers-one-at-256-bits,
  title  = {TLS certificates and secure SIP failures: source note siptls-fourteen-ciphers-one-at-256-bits},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/siptls-fourteen-ciphers-one-at-256-bits},
  note   = {Source note siptls-fourteen-ciphers-one-at-256-bits, checked 2026-09-16}
}

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