Voice-over Metro Wifi

[umqombothi]

Hi there,

Wondering if anyone has any comments on using Voice-over-Wifi for a metro area network, such as those by Tropos Networks or a Vivato solution deployed on a metro wide basis.

Is this at all possible? Or would QoS, coverage etc make the service all but unusable?

Cheers,
Umq.

[lwheeler]

Anything is possible. As long as you can control the ingress, egress and the points between for QoS. It can be done.
Larry

[jsicuran]

voip with no compression or just g711 is 64kbs at higher compression per call you can get it down to 8kbs plenty to fit on that 500k link after the protocol overhead from 1mb at the farthest distance from the ap.

[BER_vs_SNR]

You are right. There are plenty of vocoders already out there and a massive research move towards advanced low-bit-rate vocoding techniques (from both government and industry/academia) that will allow you to go even lower than 8kbps and yet preserve quality of recognition at voice reconstruction time.

Also the work from IEEE 802.11e is addressing QoS issues in a more robust and consistent way and you will soon see good VoIP over metro or LAN Wi-Fi. A little patience.

[jsicuran]

So true...It is getting crazy and wild out there. I mean now there are wifi phones and dual cell/wifi phones out there. Not bragging but I called this out in 2k when discussing technologies futures with a buddy. We were discussing Bluetooth and WAP back then. I told him WAP was WACK!!!. Wap was just taking two steps backward to just go one step forward with cells. I mentioned that whoever gets to build out a local or national 802.11 or x network first will own the world figuratively.

How?

Well IBM has 1 gig drives the size of a quarter and getting smaller, PDA technology is getting much better, faster and cheaper couple that with LAN speed wireless access that is ubiquitous then who will not need wap or cell phones. That pda can do real color and user a normal browser and surf the internet at decent speeds. The access will have the capability to handle voip which is advancing also. So, in a pda you have a full browser and possibly the ability to do voip also all over 802.11 or x technology. Screw wap, Bluetooth and pcs/cdma. And I stated that back in the summer of 2k.

It is or may start to get to that now. Verizon and AT&T are putting APs in phone booths, now imagine if AP were on ever 5th light pole or telephone in your area, similar coverage. In fact, as an example in my area a light post across the street from me has this little box hanging from it with a little omni directional antenna hanging down pointing towards the street. I asked the phone guy what that was and he said it was a cellular booster/repeater for the evening. So, if they are willing to do that then why not just an AP?

AT&T is building out the hotspots etc. The telcos are all entertaining this technology for they are afraid that someone else could build out a network( a utility or somtehing like it) then who would use their wired or cell service in the local markets or worse nationally. It is exciting because we are experiencing the infant stages of this possible convergence evolution.


Regards..

[BER_vs_SNR]

I agree with you.

The sooner the handoff issues (especially when moving at high speeds) are resolved (Lucent has already demonstarted soft handoff capabilities, however still at the development level, earlier this year) and standardized for Wi-Fi the sooner the CDMA/UMTS realm will feel the pinch, which Qualcomm did not expect a few years ago.

I am also seconding your WAP thoughts. Back in 1999 when I was selling my startup in a succesfull IPO, all my Wall Street investment banker contacts were talking about the WAP-craze as if it was panacea coming. Look where it all went!

On top of 802.11 I will add to the forecast the high speed solution 802.20 is bound to create. This revolution is HUGE and it is already swelling! The amazing thing is that new breakthroughs in deep UV photolithography enable a whole new generation of semiconductors that will enable the integrated RF technology needed to provide meaningful devices. It is the same sort of event of what happened in the 80's with the PC. If semiconductor technology had not enabled afforable execution of millions of instructions per second Microsoft would not have flourished no matter how much they tried.

Interesting times indeed!