2 way voice as in GTalk - voip

Can you tell me how GTalk implements 2 way voice communication?
The interaction happens without any latency even at a low bandwidth. Can we implement something like this in a website?
Can VOIP be implemented via a website without any need for a phone, with minimum 2 way voice carry delay?
Can any one please help me find some tutorials as well regarding this?
Thanks a bunch..

Have a look at libjingle which Google Talk uses, they have a few examples for different platforms using voice chat.
http://code.google.com/apis/talk/libjingle/index.html

Related

Is there way to detect a certain phone from a few feet away

I am trying to build a system with a raspberry pi that allows clients access into a building depending on their membership status. Right now, it uses QR codes, but I want to know if it is possible to add a feature where it uses some technology like NFC or RFID or Bluetooth to detect their phone or RFID card from at least a foot away and confirm they have a membership.
Someone told me I could use RFID, but I am only aware of that being used in short-distance applications, like a card on a hotel door. I am not sure about Bluetooth either, because the phone would have to connect to the pi first, right? Maybe there is something I don't know about. So please offer any suggestions. Thanks
I think bluetooth does good work for tracking user. Since it's the best to handle large distances than NFC and RFID these two technologies are used for low range scenarios, check this link.
In addition, you can check distance(using Proximity and RSSI) and membership status as well. but you need to know how to handle bluetooth connectivity with raspberry pi check this link. as well create an app on that mobile phone to use Bluetooth (depending which OS you're using for Android, iOS).
Regards,

IRC channel for Java Mobile development?

I'm trying to get an idea of how difficult it would be to build a simple application for feature phones, and the best way I can come up with is to learn the Java for Mobile Devices framework and dive into writing something.
However, I'd like to be able to chat with other developers when I run into problems, and I haven't really been able to find local JavaME meetups. Does anyone know of an IRC channel for JavaME in general or MIDlet development specifically?
##j2me on freenode there is also ##blackberry
They are generally very friends although the channel can be quiet at times since most people idle.

VoIP client in a browser?

Google just announced that they will add support for VoIP calls in its Gmail application.
Does someone know how this will work? Did they manage to write a web-based VoIP client, or will they require the user to have Google Talk installed and somehow (how?) call this app from the browser?
I'd also like to provide customers with a way to make/receive calls through their browser, so that they wouldn't have to install an SIP client.
Thank you.
Google don't use a VoIP client in a browser. Instead the browser is used to initiate a callback to a phone number you must have previously registered. Once you answer that call Google Voice will then ring the destination number you specified and then bridge the calls together.
I've just noticed that in my inbox. They ask you to accept their EULA to start installing Google Voice. So it's not really a browser solution.
There are several companies that have built VoIP clients as e.g. Java applets.
It is totally doable, although depending on the exact requirements it may be expensive and time consuming: for instance, echo cancellation is not exactly trivial when you need to deal with arbitrary audio drivers across any and all laptops, netbooks etc out there.
There are also consulting firms that can help with that.
Full disclaimer: I own one such company ;)

Sending an SMS from mobile browser

Is it possible for a mobile browser to send an SMS using the device's built-in capabilities?
By that I mean, NOT using some online SMS services provider but actually making the mobile device send the SMS (same you would do using J2ME).
There are lots of different mobile browsers out there, so I doubt that this is standardised. Safari/iPhone supports SMS URIs, which strikes me as a sensible approach to the problem and one that might be more widely supported than just the iPhone.
Based on the link (above) I found, and a comment from Zamel, I suspect this would work:
SMS
Although with a real phone number, and possibly escaping the + sign as %2B.
Some versions of the Opera Mini browser provide a javascript interface for authoring SMS messages to be sent from the user's phone.
Also, some versions of Nokia's Symbian browser include a javascript interface with similar functionality.
There might be others, but these are the only two I've found documentation for so far.
I think a GSM modem is capable of acting as a SMS Gateway but you have to have the software installed on the modem to do this. You might also look into the Carrier Gateway Emails to SMS as another option. Example is AT&T number#txt.att.net
There are a couple of free services popping up these days like ZeepMobile that you might also want to look into.
What exactly are you trying to accomplish?
No as a mobile browser is specifically built to render markup (html) documents. Therefore, if you wanted to send SMS via a mobile browser it would call a web server page and send from the server NOT the mobile browser.
Mobile OS and their applications have quite a lot of limitations. The closest you will see is the ability to hyperlink a phone # in a mobile browser to send a message but it will be handled via their SMS app not the browser.
Its not possible . You can call device functionality from browser . That is the way to go about it . Webkit lets you do it
Android and blackberry support
"mailto:" and "tel:".
Android supports "sms:" (and maybe iPhone, I don't have one :))
good luck and please post your result.
It's a good thing that is not possible. It would be quite a security risk IMHO. I imagine spammers would be all over it.

How can I know what bluetooth stacks are installed in my cellphone and how to they works?

I want to send almost 4k size data to any cellphone by using bluetooth.
Firstly to do this, I need to find what stacks are in my phone and what stacks are acting when I send a data.
I really struggle to find the way; however, it is really hard.
If you know how to find it, please give me some information!!
See http://32feet.NET if you are talking about Windows Mobile. It is a managed library for Bluetooth, OBEX, and IrDA. We support both the Microsoft stack, but also have support for Widcomm. And now also Bluesoleil and Stonestreet One Bluetopia.
You can either send and receive the data as an OBEX message, or over a simple bluetooth connection. See a copy of the user's guide at http://www.alanjmcf.me.uk/comms/bluetooth/32feet.NET%20—%20User’s%20Guide.html
Goto "https://www.bluetooth.org/tpg/listings.cfm" type the name of your mobile. This will give you information on the Bluetooth stack inside and the profiles supported.

Resources