High-Speed Downlink Packet Access (HSDPA) is also known as High-Speed Downlink Protocol Access. HSDPA is a protocol for mobile telephones. It is a third-generation (3G) High-Speed Packet Access technology designed to speed up network capacity and data transmission rate of cellular phones.

HSDPA is associated with various Universal Mobile Telecommunications System (UMTS) networks. These include the Global System for Mobile (GSM) Communications.

Currently, HSDPA can support speeds ranging from 1.8 Mbps to 14.4 Mbps. While this is not very fast compared to various wired networks, it is a major milestone considering the speed available to cellular technology.

Although HSDPA is mostly identified with its downlink speeds, it also has the ability to greatly expand transfer capacity. HSDPA networks can transfer up to 30 GB of data monthly and as much as 300 minutes of cellular television viewing and 1000 minutes of talk time.

Current HSDPA Technology

At present, there are 100 HSDPA-capable networks operating in 54 countries worldwide. A large number of these networks offer 3.6 Mbps downlink speeds. However, more networks are beginning to switch to faster 7.2 Mbps downlink speeds. Only a number of networks presently offer a full 14.4 Mbps speed

HSDPA competes with a rival format, the Evolution Data Optimized (EVDO) provided by Code Division Multiple Access (CDMA) cellular providers.

HSDPA Capable Devices

Aside from having a cellular plan with a company offering HSDPA access, the only requirement for logging into the HSDPA network is having a cellular device capable of using the technology. A current total of 171 handset models and other mobile devices can use an HSDPA network. Some of these HSDPA capable devices are famous cellular brand and model names such as the Nokia N95, the Palm Treo 750, and the Motorola RAZR as well as many of its various versions.

In addition to the various HSDPA handsets in the market, several HSDPA notebooks and laptops with access to the data network are available. Such products are offered by several major computer manufacturers including Dell, Acer, Hewlett-Packard, Siemens, Fujitsu, Panasonic, and Lenovo.

Future HSDPA Technology

Although 14.4 Mbps is the current cap on downlink speed over HSDPA, networks are preparing to be upgraded with a new type of HSDPA system. Dubbed as HSPA Evolved, this new HSDPA technology is designed to increase download speeds to 42 Mbps upon release, with the possibility of reaching greater speed values in the future.