A company moves its business online - Edexcel - GCSE Computer Science - Question 7 - 2021 - Paper 1

The IMAP protocol is more suitable for accessing work email from multiple devices because it allows users to manage their emails directly on the mail server. This means that if an employee reads or deletes an email on their smartphone, these changes are reflected on the laptop as well. In contrast, POP3 downloads emails to a single device and removes them from the server, which can lead to inconsistent email states across devices.

The Transmission Control Protocol (TCP) plays a critical role in data communication by ensuring reliable transmission. It establishes a connection between the sender and receiver, breaks down large data into smaller packets, and ensures that these packets are sent, received, and reassembled in the correct order. TCP also handles error checking and retransmission of lost packets to ensure data integrity.

In a client-server network, a server responds to incoming client requests by supplying services or resources. It can store and manage data, resources, or files, and it processes requests from clients, delivering the requested data or services accordingly.

In a bus topology, all devices are connected to a single central cable (the bus). Each device has a single connection to this bus, ensuring that data can be transmitted to any device on the network without direct connection to one another.