According to various online reports, the speed and reliability of the AT&T network have come under the scanner yet another time, with a number of users having complained about a significant slow-down in the carrier’s wireless data speeds over the weekend and through Tuesday.

Going by the complaints of the users, the upload speeds on the AT&T network have, over the past couple of days, have virtually crawled to below 100 Kbps – which is as slow as the speed of the dial-up connections.

The comments on tech blog Gizmodo and the forums at MacRumors indicate that the iPhone users in some of the biggest metropolitan cities in the US have been witnessing a pathetic drop in the AT&T data upload speeds in the last few days; even though the download speeds have largely been hovering above 1 Mpbs.

As per The Unofficial Apple Weblog, which first reported the infuriatingly slow speed of the AT&T network, the areas most affected by the speed slow-down include – New York City, Central Jersey, Boston, Orlando, Seattle, South Jersey/Philly, Columbus, Cleveland, West Houston, Phoenix, Northern Colorado, St. Paul/Minnesota, Suffolk County/Long Island, Quad Cities, Denver, Detroit Metro, and Cincinnati.

While there has been no official explanation put forth by AT&T about the slow data upload speeds, most of the iPhone users believe that the new ‘slow’ speeds are probably a cap; and that the carrier is deliberately throttling its network to slow down Web-access speeds.