HSDPA : (High Speed Downlink Packet Acces) is a HP protocol that is often referred to as 3.5 G. Internet Access of HSDPA maximum is 14.1 Mbps
EDGE : (Enhanced Data rates for GSM Evolution) is next generation of GPRS technology develop. EDGE is also often called by the term 2.75 G. EDGE is faster than GPRS. Maximum speed transfer data can be done with EDGE technology is 473.6 Kbps.
UMTS : (Universal Mobile Telecommunications Service) is a third-generation (3G) broadband, packet-based transmission of text, digitized voice, video, and multimedia at data rates up to 2 megabits per second (Mbps). UMTS offers a consistent set of services to mobile computer and phone users, no matter where they are located in the world.