> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media.md). # Voice and media - [Voice and media](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/voice-media.md) - [AMR](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/amr.md) - [ASR](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/asr.md) - [Audio Mixers](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/audio-mixers.md) - [Automatic Gain Control](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/automatic-gain-control.md) - [Bridging Service](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/bridging-service.md) - [Call Flow](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/call-flow.md) - [Call statistics format](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/call-statistics-format.md) - [Clearmode](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/clearmode.md) - [Custom SIP BYE headers format](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/custom-sip-bye-headers-format.md) - [DTMF Relay](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/dtmf-relay.md): DTMF relay: how a VoIP gateway detects in-call tones and forwards them by the negotiated method, so digits survive compressed codecs instead of degrading. - [Editing Custom SIP BYE headers format](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/editing-custom-sip-bye-headers-format.md) - [G.722.2 (AMR-WB)](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/g-722-2-amr-wb.md) - [GSM-EFR](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/gsm-efr.md) - [GSM-FR](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/gsm-fr.md) - [GSM-R](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/gsm-r.md): GSM-R, the GSM variant used for railway communication under ERTMS, and where TelcoBridges gateways fit into a GSM-R network. - [H.263](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/h-263.md) - [H.264](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/h-264.md) - [Ringback tones](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/ringback-tones.md): What a ringback tone (RBT) is, how it differs from the ring the called party hears, and how Tmedia and Tdev generate ringback and custom RBT services. - [sRTP relay support for encrypted SIP interconnections](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/srtp-relay-support-for-encrypted-sip-interconnections.md) - [Support sRTP encoding and decoding](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/support-srtp-encoding-and-decoding.md): sRTP encoding and decoding on FreeSBC and ProSBC: terminating encrypted media at the network boundary and relaying it as plain RTP inside. SBC 3.1. - [Target Recording](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/target-recording.md) - [Tone definitions](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/tone-definitions.md) - [Toolpack: Configuring Fax Relay](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/toolpack-configuring-fax-relay.md) - [Transcoding](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/transcoding.md) - [UMTS](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/umts.md) - [Video codecs](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/video-codecs.md) - [Voice Codecs](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/voice-codecs.md) --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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