VoIP reviews, news, tutorials

I've been browsing Wi-Fi Plant website and came across the following interesting pages related to VoIP.

[List of VoIP articles]
[Skype vs. Other VoIP providers]

Adding a Mic jack to iTouch phone - use with VoIP!

I just got a 16Gig iTouch as a gift and almost immediately went to search for hardware hacks for it. To my pleasant surprise, iTouch has a microphone circuitry inside allowing one to activate it! The guys at www.touchmods.net created an iTouch USB to mic converter and a software that can be installed on the jailbroken gadget to allow the happy owners to make VoIP calls.

VoIP call demo from touchmods
Freeappleipodtouch.com's tutorial link

There's another cool hack that allows using Motorola bluetooth headset with iTouch: link

These are the great hacks! I needed the voice recording capability and it looks as it's possible without the need for the second device!

Good job, the Touchmods team!

VoIP over GPRS or EDGE/EGPRS

Wouldn't it be possible to use VoIP over GPRS or EGPRS that is already supported by cell phones, thus, minimizing the number of minutes used from a regular plan?

I think technically it should work, since in both networks, data and voice 'calls' are made simultaneously using different time slots. So, if using one time slot per voice call is OK (that's what everyone is doing when calling), using the remaining time slots for data (one or more if paid for more) should allow encoding VoIP packets and transferring them via data channel.

The problems that need to be solved here are: (1) mobile hardware/software to allow fast packet creation and extraction and (2) cost effectiveness of this method. Cell phones are quite fast these days with majority of new cell phones and hand held devices supporting video decoding and even streaming over fast data connection (i.e. iPhone over WiFi). That means that hardware is fast enough to be able to packetize the voice. The second problem can depend on the data plan that a user pays for. Does it make sense to pay more for data and squeeze more minutes from a mobile plan over data channel? I think unlimited data plans can solve these problems.

Data plans are usually quite pricey. However, just last week Virgin Mobile in Canada announced Unlimited data plan option for just $10 on top of a regular cell phone plan. That should push other providers in Canada to decrease their rates soon as well!

References:
$10 Unlimited Data Virgin Mobile plan: link
Easy explanation of GPRS and EDGE: link

Spectrum Analyzer to Hunt Wireless VoIP Interference

WLAN is using the unlicensed frequency bands, which are shared among numerous applications including some cordless phones. In this article, Cognio's Spectrum Expert frequency analyzer is tested in action by Mike Outmesguine, the president and founder of TransStellar Inc. (and the author of the book I had the chance to look at, "Wi-Fi Toys - 15 Cool Wireless Projects For Home, Office, and Entertainment").

Outmesguine examined his Wi-Fi network and observed a slowdown when multiple cordless phones were turned on. As they were fighting for the same spectrum with Wi-Fi, the speed of the connection decreased. Spectrum analyzer showed the increased power coming from the phones. The speed was restored once the phones were turned off.

Read the article here