It generally subscribes a 2nd generation cellular system
merged with General Packet Radio Services (GPRS) and
other amenities doesn’t commonly endow in 2G or 1G
networks. A 2.5G system generally uses 2G system
frameworks, but it applies packet switching along with
circuit switching. It can assist data rate up to 144kbps. The
main 2.5G technologies were GPRS, Enhanced Data Rate
for GSM Evolution (EDGE), and Code Division Multiple
Access (CDMA) 2000 [3], [7].