2.1 Routing Tech

Question 1

Static Routing

Answer 1

Manual entry of routes into a routing table. Best for small, non-changing networks or a default route (0.0.0.0/0).

Question 2

Dynamic Routing

Answer 2

Protocols that automatically discover and update routes based on network changes (e.g., OSPF, BGP).

Question 3

BGP (Border Gateway Protocol)

Answer 3

An Exterior Gateway Protocol (EGP) used to route data between Autonomous Systems (the protocol of the Internet).

Question 4

EIGRP

Answer 4

An advanced distance-vector (hybrid) protocol developed by Cisco; uses bandwidth and delay as metrics.

Question 5

OSPF (Open Shortest Path First)

Answer 5

A link-state routing protocol that uses cost (based on bandwidth) to determine the best path; fast convergence.

Question 6

Administrative Distance (AD)

Answer 6

A value used to rate the ‘trustworthiness’ of a route source. (Lower value = more trusted).

Question 7

Prefix Length

Answer 7

The number of bits set in a subnet mask (e.g., /24); used by routers to find the ‘longest match’ for route selection.

Question 8

Metric

Answer 8

A value assigned to a route (hop count, cost, etc.) to help a router choose the best path when multiple routes exist.

Question 9

NAT (Network Address Translation)

Answer 9

Translates a private IP address to a public IP address to allow internet access.

Question 10

PAT (Port Address Translation)

Answer 10

A type of NAT (NAT Overload) that allows multiple private IPs to share one public IP by assigning unique port numbers.

Question 11

FHRP (First Hop Redundancy Protocol)

Answer 11

A class of protocols (like HSRP or VRRP) that provides a backup gateway by allowing multiple routers to share a single virtual IP.

Question 12

Virtual IP (VIP)

Answer 12

An IP address not tied to a specific physical interface; used in FHRP or load balancing for redundancy.

Question 13

Subinterfaces

Answer 13

Logical interfaces created on a single physical interface (Router-on-a-stick) to allow routing between multiple VLANs.