3G typically operates in separate frequencies than 2G and 2.5G uses , thus allowing mobile phones to switch from one to the other when capable. Summary: 2.5G implements packet switching along with the circuit switching in 2G. 2.5G has much faster data rates than 2G.
Read moreWhat are the main difference between 2G 3G 4G 5G?
The speed increases and the technology used to achieve that speed also changes. For eg, 1G offers 2.4 kbps, 2G offers 64 Kbps and is based on GSM, 3G offers 144 kbps-2 mbps whereas 4G offers 100 Mbps – 1 Gbps and is based on LTE technology .
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