How is "bandwidth" defined in the context of networks?

Bandwidth, in the context of networks, is defined as the maximum rate of data transfer across a network connection. This measurement is typically expressed in bits per second (bps) or its multiples, such as kilobits per second (kbps) or megabits per second (Mbps). It indicates how much data can be transmitted over a network at a given time and directly correlates to the speed and efficiency of data transmission. Higher bandwidth allows for faster downloads, smoother streaming, and better performance for applications that rely on frequent data exchanges.

The other options relate to different aspects of network functionality but do not define bandwidth. The speed of encryption processes is relevant to network security and data protection, not to the data transfer capacity itself. The level of security provided by firewalls pertains to network safety rather than data transfer rates. Lastly, the ability of malware to spread is a concern in cybersecurity but is unrelated to the definition of bandwidth. Understanding that bandwidth focuses specifically on the capacity for data transfer helps clarify its significance in networking.