DNS, codecs, and the default voice · Sources and go deeper

Sources and go deeper

• Technical requirements PDF. vendor. last checked 2026-10. Fetched for this lab in October 2026. Re-read before you buy hardware or open a firewall.
• SIP trunk options chapter. vendor. last checked 2026-10.
• RFC 3261. rfc. last checked 2026-10.
• RFC 4733. rfc. last checked 2026-10.
• RFC 3550, RTP. rfc. last checked 2026-10.
• RFC 3551, RTP profile for audio and video. rfc. last checked 2026-10.
• ITU-T G.711. standard. last checked 2026-10.
• RFC 1035, domain names. rfc. last checked 2026-10.
• RFC 2782, DNS SRV. rfc. last checked 2026-10.
• confirm. A 20 ms packet time is a practitioner note about Cisco gateways, not a figure quoted from the Five9 technical requirements in this lab. last checked 2026-10.