面试题与答案

Subnetting is the process of dividing a network into sub-networks to improve performance and security. It helps manage IP addresses more efficiently.

NAT allows multiple devices on a local network to share a single public IP address, providing security and conserving IP addresses.

STP prevents loops in Ethernet networks by blocking redundant paths. It ensures a loop-free topology and rapid convergence in case of link failures.

OSPF is a link-state routing protocol that calculates the shortest path to a destination based on a SPF (Shortest Path First) algorithm.

EIGRP is a Cisco proprietary routing protocol that uses a composite metric based on bandwidth, delay, reliability, and load to determine the best path.

VLSM allows the use of different subnet mask lengths in the same IP network, optimizing IP address allocation.

BGP is an exterior gateway protocol used for routing between different autonomous systems. It is critical for Internet routing.

ARP poisoning is a method used by attackers to associate their MAC address with the IP address of another device, leading to traffic interception.

GRE is a tunneling protocol that encapsulates a wide variety of network layer protocols inside point-to-point connections.

The Session layer manages sessions (connections) between applications. It establishes, maintains, and terminates communication sessions.

CIDR is a method of allocating IP addresses and routing IP packets based on variable-length subnet masking, improving the efficiency of address space usage.