Following up a message from our Twitter account earlier today, it seems AT&T is upgrading their data network to what is called HSPA speed. HSPA, or High Speed Packet Access, will allow AT&T customers on smartphones (such as the iPhone) or with mobile broadband cards to access the web at a higher rate of speed than the current 3G speed. The technology for the speed upgrade already exists in the hardware that is on the market today, testing has begun on the technology in a few key AT&T markets.

According to the GSM Association, HSDPA can support download speeds of 7.2 Mbps, while HSPA+ can support speeds of up to 42 Mbps in the downlink and 11 Mbps in the uplink. CEO Ralph de la Vega says AT&T will likely skip upgrading its network to 14.4Mbps and jump directly from 7.2Mbps to 21Mbps using HSPA+ (also known as HSPA Evolution).

If you’re an AT&T mobile user, this is great news as we become more and more dependent on our mobile devices to keep us connected with the rest of the world.