Report: AT&T throttling 3G upload speeds

AT&T is reportedly throttling 3G uploads in a number of cities, including NYC, Boston, Seattle, Las Vegas and Washington, D.C.

Indeed, one NYC iPhone owner estimated that 3G upload speeds have been unceremoniously capped at a paltry 100kbs.

“It looks to me like folks at AT&T realized how much bandwidth the new Apple [iPhone 4] is able to consume, and immediately capped the upload speed at 100kbs!!!!! This MURDERS the latency, and of course slows the download speed,” Milan03 wrote in a Mac Rumors forum post.

“I went out last night to the exact same location where exactly a week ago I was constantly getting almost 5mbps down and 1.7mbps up, with latency under 300ms, tested under the exact same circumstances. I should also mention that I did my testing in midtown Manhattan, at about 11pm on a Saturday night, when pretty much no one was on the cell tower plant’s load.

However, Marc of IntoMobile cautioned that there was no way of definitively knowing if the alleged cap was a temporary or permanent restriction imposed by the carrier.

“…But it is extremely annoying for users who are trying to upload pictures, videos or anything else.

“There is word that this could be a result of an outage or maintenance, but we don’t know for sure just yet. [Still], it’s tough to say that it is a local or even a small, regional outage due to the fact that [a number of] cities all seem to be affected.”

AT&T has yet to comment on the issue.