[BryanHarig]

Sprint does have a sizable amount of fiber optic backbone lines. But that only helps so much, those lines dont run to each and every one of their 15000+ cell sites.

Most cell sites are connected to the larger data network by a single T1 line. Meaning that it will max out at about 1.4Mbps (or less if it is under heavy use). It would be a very expensive proposition for Sprint to begin to upgrade those backhaul connections over their entire network (or a small part of it) to support 40 or 50 Mbps connections. Especially since there will be no real additional profit in doing so. The Rev A network they have is sufficent to power all the value added services they make money on: Sprint TV, Telenav, Ready Link, HP-PTT etc. It would cost an absurd amount of money to upgrade the backhaul connections to support 40-50 Mbps connections and it would not materially improve the performance of any of these services.

If anything it would reduce their profits because people like me would use it as their primary internet connection and pull down hundreds of gigs a month.

Bottom line: until there is a need or real competition Sprint wont do the Rev B upgrade.

[Turkish_Leprechaun]

You have a good point there, however one argument is there are people willing to pay more for faster speeds! I know a few network administrators who have found ways to harvest the true power of the blackberry seeing how the OS of the blackberry is unix based they have installed custom shells on them and use them to access their servers remotely with ssh and I even seen this one on a new 8830 but a micro x-server connected to his remote workstation! It was the craziest thing! Couldn't take a picture because the guy making it doesn't have a patent for it yet or something like that...

Also, for the network, non of the towers are connected via T1, if they're not on fiber then they're on copper, 1.5 Mbps is not fast enough to support a tower by itself, a single digital voice call alone uses over 50 kbps.

[BryanHarig]

Originally Posted by Turkish_Leprechaun

...

Also, for the network, non of the towers are connected via T1, if they're not on fiber then they're on copper, 1.5 Mbps is not fast enough to support a tower by itself, a single digital voice call alone uses over 50 kbps.

Sprint phones use either 13kbps or 8kbps EVRC codecs depending on the age and manufacturer of the phone.

Cell sites use T1 lines. In areas of high bandwith use they may have several. In areas where T1 service is unavailable there are other alternatives (like microwave links), however these are very rare and do not offer optimal performance.

CDMA is a technology that allows each call to be encoded with a unique PR code and spread across the available frequency. It does not require a fixed amount of bandwith held open for the duration of a call. As the bandwith used aproaches maximum soft capacity limits will kick in to degrade the quality of all users calls equally and allow even more traffic in times of high usage.

Various methods

Code division multiple access - Wikipedia, the free encyclopedia

I am not a network engineer so I am not able to provide much more detail then that.