About this proposal:
1. Backgroud
2. SIP brief intro
3. SIP vs. JXTA
4. DisVoIP bootstrap
Part1: Background
Wireless telephony in the future, 3G? We maybe want to have some alternatives, such as using the Wi-Fi and Skype on WinCE, thought it’s seems somehow awkward, but 802.16 and the WiMAX/Wi-Fi combined wireless world vision did incited my imagination to pursue the possibly, the so-call “WiMAX Phone”: a hand-held device provides VoIP and multimedia service which highly relevant to Web. No matter it’s hype or not: but I did see Skype becoming popular, while none of them think they would use Skype to dial an emergency number.
I believe wireless VoIP will be popular, as the wireless network and hand-held device evolves, and it will be revolutionary, so it’s time to start something, proposing project, named DisVoIP (distributed voice over IP).
Skype is a P2P application, I didn’t get who it works, but as the same to many P2P applications, you need a identity, and a network get the line to you correctly all behind the scene.
So I looked for some open standards suits such job. SIP is indented from the bottom.
Part2: SIP brief intro
Here is a simple digestion of what SIP is from sipcenter.com; hopefully you can get the picture that how it looks like the JXTA.
SIP (session initiation protocol) is a request-response signaling protocol which closely resembles two other Internet protocols, HTTP and SMTP (the protocols that power the World Wide Web and email); consequently, SIP sits comfortably alongside Internet applications. Using SIP, telephony becomes another web application and integrates easily into other Internet services. SIP is a simple toolkit that service providers can use to build converged voice and multimedia services.
There are two basic components within SIP: the SIP user agent and the SIP network server. The user agent is the end system component for the call and the SIP server is the network device that handles the signaling associated with multiple calls. SIP user agents can be lightweight clients suitable for embedding in end-user devices such as mobile handsets or PDAs. Alternatively, they can be desktop applications that bind with other software applications such as contact managers. The main function of the SIP servers is to provide name resolution and user location, since the caller is unlikely to know the IP address or host name of the called party, and to pass on messages to other servers using next hop routing protocols.
You can visit www.sipcenter.com for a full review.
A PDF version of SIP introduction you can find at:
http://www.sipcenter.com/sip.nsf/html/WEBB5YNVK8/$FILE/Ubiquity_SIP_Overview.pdf
A flash you can get a quick review of how SIP peers get connected (very intuitive)
http://www.sipcenter.com/sip.nsf/html/WEBB5YHVY5/$FILE/SIPoverviewPC.zip
Ok, as you’ve go this far, don’t you now just wondering how this related to JXTA? Everything! As its core design promised such a virtual network .
Part3 SIP vs. JXTA
Doug's Inner Net News: SIP and JXTA: "SIP is complex. JXTA is relatively simple. I'm not exactly sure why that is so. SIP is used for call control in IP telephony, and call control in the PSTN is complex. But I have to wonder if SIP would not have been simpler if it had started with a model of peer-to-peer communication like that in JXTA. If I were to start work on a new peer-to-peer protocol, I would consider building upon JXTA."
The robustness and language characteristics inherited from Java, provides us even some advantages.
l Hybridizing with other JXTA application
l Can be integrated into present Web Application as an alternative component.
l Still to be discovered…
Part4 bootstrap
The project name DisVoIP, was influenced how Brad Neuberg named his JXTA based DNS-like system. And the bootstrap experiment of VoIP, also relied on his JXTA p2psockets project at http://p2psockets.jxta.org/, (owner: Brad Neuberg), provides a platform to test how DisVoIP look like. And this is the most important difference from VoP2P, since DisVoIP would be a Web Service based component in p2psockets or its own standalone comparable environment. HTTP connection p2psockets will deliver our first audio stream transfer experiment.
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