HSDPA (High-Speed Downlink Packet Access) is a 3G enhancement is a new mobile data protocol and is sometimes referred to as a 3.5G.HSDPA speeds can reach 3.6 Mbps downstream and 348 Kbps upstream. HSDPA-plus provids much more faster speed.
See : Difference between 3G and HSDPA
Book Release "The Emergency" by Dr.Subramanyan Swamy
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