The correct answer is: D. New packet overlay including routers and gateways.
GPRS (General Packet Radio Service) is a packet-switched mobile data service that enables users to send and receive data over a cellular network. It is an upgrade to GSM (Global System for Mobile Communications), the most widely used cellular network technology in the world.
GPRS works by dividing the radio time into small time slots, which are then used to carry data packets. This is in contrast to GSM, which uses circuit-switched connections for voice calls. Circuit-switched connections are dedicated to a single user for the duration of the call, while packet-switched connections are shared by multiple users. This makes GPRS more efficient than GSM for data transmission.
To upgrade from GSM to GPRS, a cellular network operator needs to install new packet-switched infrastructure, including routers and gateways. These devices are responsible for routing data packets between the cellular network and the Internet.
The other options are incorrect because they do not represent the necessary changes to upgrade from GSM to GPRS.
- Option A is incorrect because a whole new base station is not required. The existing base stations can be used with GPRS.
- Option B is incorrect because a new transceiver at the base station is not required. The existing transceivers can be used with GPRS.
- Option C is incorrect because new channel cards are not required. The existing channel cards can be used with GPRS.