Final answer:
The redir flag in a session table signifies a redirected session, meaning the network traffic is rerouted through a different path than initially intended, often for security or traffic management purposes.
Step-by-step explanation:
When discussing network security and session management, particularly in the context of firewalls and network monitoring, the redir flag in a session table commonly signifies a redirected session. This means that the session, typically a network connection or conversation between two endpoints, has been rerouted from its original path. The redirection could be for various reasons, such as load balancing, security purposes, or to pass the traffic through an intermediary device like a proxy server or a traffic analysis tool.
In the options presented, the correct answer would be (a) Redirected session. This indicates that the traffic for this session is not following the normal route directly between source and destination, but is instead being redirected through a different path. This could allow for traffic control, monitoring, or applying certain policies before the data reaches its intended destination.
It is essential in network administration and security to understand how flags in a session table operate. Redirection can play a pivotal role in securing networks against threats by ensuring that traffic is inspected or modified by security appliances, or even just ensuring optimal traffic flow across the network infrastructure.