KphoneSI (kpsi) is a SIP (Session Initiation Protocol) user agent
for Linux, with which you can initiate VoIP (Voice over IP) connections
over the Internet, send Instant Messages, subscribe your friends
presence information and start other applications of your choice
Session Initiation Protocol (SIP) [1] is fast becoming the protocol of choice for IP based communication
– specifically telephony (Voice over Internet Protocol - VoIP), video, and instant
messaging.
Pocket SIP Messenger is a SIP instant messaging client for small devices that use Windows CE (iPAQ Pocket PC, ...). The IM protocol is based on SIMPLE (IETF) working group s specification.
基于單DSP的VoIP模擬電話適配器研究與實現(xiàn):提出和實現(xiàn)了一種新穎的基于單個通用數(shù)字信號處理器(DSP)的VoIP模擬電話適配器方案。DSP的I/O和存儲資源非常有限，通常適于運算密集型應(yīng)用，不適宜控制密集型應(yīng)用[5]。該系統(tǒng)高效利用單DSP的I/O和片內(nèi)外存儲器資源，采用μC/OS-II嵌入式實時操作系統(tǒng)，支持SIP和TCP-UDP/IP協(xié)議，通過LAN或者寬帶接入，使普通電話機(jī)成為Internet終端，實現(xiàn)IP電話。該系統(tǒng)軟硬件結(jié)構(gòu)緊湊高效，運行穩(wěn)定，成本低，具有廣闊的應(yīng)用前景。關(guān)鍵詞：模擬電話適配器；IP電話；數(shù)字信號處理器；μC/OS-II
【Abstract】This paper presents a VoIP ATA solution based on a single digital signal processor (DSP). DSPs are suitable for arithmetic-intensiveapplication and unsuitable for control-intensive application because of the limitation of I/O and memory resources. This solution is based on a 16-bitfixed-point DSP and μC/OS-II embedded real-time operating system. It makes good use of the limited resources, supports SIP and TCP-UDP/IPprotocol. It can connect the analog telephone to Internet and realize the VoIP application. This system has a great future for its high efficiency andlow cost.【Key words】Analog telephone adapter (ATA); Voice over Internet protocol (VoIP); Digital signal processor (DSP); μC/OS-II
Research and Implementation of VoIPATA Based on Single DSP
