Asterisk学习进阶-3
都說他功能強大,那么我們就要看看他到底有哪些功能,為什么強大,體現在哪兒。我就按照功能大致進行功能分類先。Asterisk大致可以按照應用,編碼,文件,接入等功能模塊進行粗略的分解。
首先是應用:目前我們支持語音郵件,個性鈴聲,電話會議,交互應答,電話座席,三方通話,呼叫ID,通話錄音等等(后續補充)。
http://www.voip-info.org/wiki/view/Asterisk+PBX+functions
http://www.voip-info.org/wiki/view/PBX+features(列出有點多,請自行查看)
?
asterisk 相關的權威網址有兩個,www.asterisk.org?和?www.voip-info.org,需要資料請優先考慮這兩個地方。
編碼格式:?????
G.711 ulaw (as used in US)
G.711 alaw (as used in Europe)
G.723.1 - pass-thru for people who need a license , free for other people
G.726 - 32kbps in Asterisk 1.0.3, 16/24/32/40kbps in CVS HEAD.
G.729 - may require a license unless using pass-thru, free version available for use in countries without patents or for educational use only
GSM
iLBC
LPC10 (not recommended!)
Speex - configurable 4-48kbps, VBR, ABR, etc. see bug
adpcm?? (ADPCM)
slin?? ??(16 bit Signed Linear PCM)
g722?? ?(G722)
jpeg?? ??(JPEG image)
png?? ??(PNG image)
h261?? ?(H.261 Video)
h263? ??(H.263 Video)
h263p?? (H.263+ Video)
h264?? ?(H.264 Video)
?
文件格式:
adpcm????? vox??????? vox????????????????
slin?????? wav??????? wav????????????????
slin?????? sln??????? sln|raw????????????
g722?????? g722?????? g722???????????????
ulaw?????? au???????? au?????????????????
alaw?????? alaw?????? alaw|al????????????
ulaw?????? pcm??????? pcm|ulaw|ul|mu?????
gsm??????? gsm??????? gsm????????????????
h264?????? h264?????? h264???????????????
h263?????? h263?????? h263???????????????
ilbc????? ?iLBC?????? ilbc???????????????
g729?????? g729?????? g729???????????????
g726?????? g726-16??? g726-16????????????
g726?????? g726-24??? g726-24????????????
g726?????? g726-32??? g726-32????????????
g726?????? g726-40??? g726-40????????????
g723??? ???g723sf???? g723|g723sf????????
gsm??????? wav49????? WAV|wav49??
另外還可以支持MP3的文件格式。
?
語音通道:
Agent: ACD Agent channel
Console: Linux console client driver for sound cards (using OSS or ALSA)
H.323: An older VOIP protocol
IAX and IAX2: Inter-Asterisk Exchange protocol, Asterisk's own VOIP protocol
Local: Loopback into another context
MGCP: Media Gateway Control Protocol, another VOIP protocol
mISDN: mISDN channel
Modem: Confusingly, this is for connecting ISDN lines, not for use with modems. Deprecated.
NBS: using Network Broadcast Sound
phone: Linux Telephony channel
SIP: Session Initiation Protocol, the most common VOIP protocol
Skinny: A driver for Cisco Skinny Client Control Protocol (a VOIP protocol)
Gtalk: Google Talk Channel driver.
VOFR: voice over frame relay Adtran style
VPB: For connecting ordinary telephone and telephone lines using Voicetronix cards
Zap: For connecting ordinary telephones and telephone lines using Digium cards. Also for TDMoE and for Asterisk zaphfc
Celliax: let Asterisk manage GSM and CDMA cellular phones, and Skype calls to/from cellphones
Bluetooth: Allows the use of bluetooth devices to change routing - see CVS "chan_btp"
CAPI: ISDN CAPI channel
vISDN: vISDN channel (native BRI channel for HFC chipsets)
SCCP: An alternate Skinny/SCCP channel
Sirrix: ISDN BRI for Sirrix cards (with optional ISDN encryption)
UNISTIM: Nortel Unistim channel
Unicall: Replacement for zaptel, with R2 support
SS7: SS7 (ISUP on MTP2/3) channel
asterisk主體可以分為模塊裝載器,核心交換組件,編碼轉換,以及調度和IO管理。首先系統啟動的時候,通過模塊狀態器把驅動模塊進行加載和初始化,是他們能夠完成語音通道的初始化,文件格式以及應用等初始化。所有事情做完后,準備接受電話的呼叫。核心交換組件開始工作,他通過各種接口接受呼叫,例如T1/E1,sip,h323等等,接著開始檢索撥號配置文件,然后通知對端振鈴,同時連接語音郵件,外出電話或者其他的應用程序。同時他還提供了一個調度和io管理,讓驅動和應用程序之間相互協作。編碼轉換的工作就很明確,主要完成不同編碼之間的轉化以及評估。這樣整個系統就在這三個部分的有序協調下開始了工作。
總結
以上是生活随笔為你收集整理的Asterisk学习进阶-3的全部內容,希望文章能夠幫你解決所遇到的問題。
- 上一篇: PS5销量突破2000万台 索尼称今年将
- 下一篇: 泡面神器Kindle:终于远离我们而去