FreeSWITCH is an open source telephony platform designed to meet the need for voice or text-driven systems that scale from softphone to softswitch . FreeSWITCH can be used as a switch, PBX , media gateway or media server for IVR applications using simple or XML scripts to control the call processing algorithm. FreeSWITCH supports various protocols such as SIP , H.323 , IAX2 and Google Talk , which allows you to interact with sipX , OpenPBX , Bayonne , Yate , or Asterisk .
FreeSWITCH supports many advanced SIP features, such as presence / BLF / SLA, TCP TLS and sRTP . It can be used as a transparent proxy server with or without media stream proxying, work with (English) T.38 (proxying and converting T.38 to T.30 and vice versa) and other protocols.
FreeSWITCH supports narrowband and wideband codecs , making it the perfect bridge to old devices for the future. Voice channels and conferences can operate at frequencies of 8, 16, 32 and 48 kHz and allow you to combine channels with different frequencies.
Content
Platform
FreeSWITCH runs on Windows , Mac OS X , BSD , Solaris, and Linux on 32-bit and 64-bit platforms.
FreeSWITCH developers participate in other open source projects and contribute to other projects such as openSER , sipX , Asterisk and CallWeaver .
Codec Support
FreeSWITCH supports many audio codecs: [1]
- PCMU - G.711 µ-law
- PCMA - G.711 A-law
- G.722
- G.722.1
- G.722.1c
- G.726
- G.726 with AAL2 packing
- G.729 (passthrough)
- G.729 (licensed, $ 10 / channel) [2]
- GSM
- CELT and Opus
- iLBC
- DVI4 ( IMA ADPCM )
- Broadvoice
- SILK
- Speex
- CODEC2
- Siren
- LPC-10
- G.723.1 (passthrough mode only)
- AMR (passthrough mode only)
- iSAC
FreeSWITCH supports several video codecs: [1]
- H261
- H263
- H263 + ( H263-1998 )
- H263 ++ ( H263-2000 )
- H264
- VP8
- Theora (passthrough)
- MP4 (passthrough)
Some codecs are supported only in pass-through mode. This means that the compressed data is transmitted through the subscribers without any processing. Since the data is not encoded or decoded, it allows you to implement support for some codecs, which can not be implemented due to patent / license restrictions. However, in this case, the data cannot be recoded, that is, in the pass-through mode, both subscribers must use the same codec, and some recording and playback functions (such as IVR ) are not supported.
In addition, there is support for hardware recoding, for example, Sangoma production cards [3] . In this case, the codecs are implemented in hardware, which reduces the load on the processor. Some of these codecs are fully licensed, which provides an alternative to pass-through mode.
Links
Notes
- ↑ 1 2 Codecs - FreeSWITCH Wiki
- ↑ G.729A License (Linux) | FreeSWITCH Archived November 23, 2010.
- ↑ Support Wiki - Media Transcoding Archived July 5, 2013.