ITSource Technologies IT Engineer Interview Questions and Answers for Experienced

A VLAN is a virtual LAN that allows for the segmentation of network traffic to improve performance, security, and manageability.

• VLANs divide a physical network into multiple logical networks, each with its own broadcast domain.

• Devices within the same VLAN can communicate with each other as if they were connected to the same physical network.

• VLANs can be configured to isolate sensitive data or specific types of traffic ...read more

HSRP stands for Hot Standby Router Protocol, used for providing high availability in a network by allowing two or more routers to work together in a group.

• HSRP is a Cisco proprietary protocol used for redundancy in a network.

• It allows multiple routers to work together in a group, with one router being the active router and the others as standby routers.

• If the active router fails, one of the standby routers takes over a...read more

OSPF is a link-state routing protocol that uses Dijkstra's algorithm to calculate the shortest path to a destination network.

• OSPF routers exchange link-state advertisements (LSAs) to build a complete topology of the network.

• Each router calculates the shortest path to every network using Dijkstra's algorithm.

• OSPF uses cost as its metric, which is based on the bandwidth of the link.

• OSPF supports multiple areas, which red...read more

BGP is a routing protocol used to exchange routing information between different autonomous systems.

• BGP uses TCP as its transport protocol.

• It operates on a hop-by-hop basis, meaning that it only exchanges routing information with its directly connected neighbors.

• BGP uses path attributes to determine the best path for a given destination.

• BGP can be used for both IPv4 and IPv6 routing.

• BGP is commonly used by Internet Ser...read more

Copper twisted pair can be checked using a cable tester to ensure proper connectivity and identify any faults.

• Use a cable tester to check for continuity and proper wiring

• Check for any faults such as shorts, opens, or miswires

• Verify that the cable meets the required specifications for the network

• Perform a loopback test to ensure that data can be transmitted and received properly

Identifying leased line modem fault

• Check if the modem is powered on and all cables are properly connected

• Check the modem's status lights for any abnormalities

• Perform loopback tests to check for connectivity issues

• Check the modem's configuration settings

• Replace the modem if all other troubleshooting steps fail

To find the reliability of a link on Cisco routers, use the show interface command.

• Log in to the Cisco router using the console or Telnet/SSH.

• Enter the command 'show interface' to display the status of all interfaces on the router.

• Look for the 'input errors' and 'output errors' fields to determine the reliability of the link.

• If there are a high number of errors, the link may be unreliable and require troubleshooting.

• Ot...read more