Networking Interview Questions and Answers
Question - 1 : - What are the seven layers of the OSI model?
Answer - 1 : - The layers are physical, data link, network, transport, session, presentation, and application layers.
Question - 2 : - In the TCP client-servel model, how does the three-way handshake work in opening connection?
Answer - 2 : - The client first sends a packet with sequence "x" to the server. When the server receives this packet, the server will send back another packet with sequence "y", acknowledging the request of the client. When the client receives the acknowledgement from the server, the client will then send an acknowledge back to the server for acknowledging that sequence "y" has been received.
Question - 3 : - What is the purpose of exchanging beginning sequence numbers during the the connection in the TCP client-server model?
Answer - 3 : - To ensure that any data lost during data transfer can be retransmitted.
Question - 4 : - How does Asynchronous Transfer Mode (ATM) work?
Answer - 4 : - ATM works by transmitting all traffic in small, fixed-sized cells. These small, fixed-size cells reduces queuing delay and can be switched quickly. ATM fits into layer 2 of the OSI model and provides functions for framing and error correction. At the port interface, ATM switches convert cells into frames, and vice versa. ATM provides Quality of Service and traffic shaping.
Question - 5 : - Given a Class B Network with subnet mask of 255.255.248.0 and a packet addressed to 130.40.32.16, what is the subnet address?
Answer - 5 : - Take the 2 addresses, write them in binary form, then AND them. The answer is 130.40.32.0
Question - 6 : - What is a default gateway?
Answer - 6 : - The exit-point from one network and entry-way into another network, often the router of the network.
Question - 7 : - How do you set a default route on an IOS Cisco router?
Answer - 7 : - ip route 0.0.0.0 0.0.0.0 x.x.x.x [where x.x.x.x represents the destination address]
Question - 8 : - What is the difference between a domain local group and a global group?
Answer - 8 : - Domain local groups grant permissions to objects within the domain in which the reside. Global groups contain grant permissions tree or forest wide for any objects within the Active Directory.
Question - 9 : - What is LDAP used for?
Answer - 9 : - LDAP is a set of protocol used for providing access to information directories.
Question - 10 : - What tool have you used to create and analyze packet captures?
Answer - 10 : - Network Monitor in Win2K / Win2K3, Ethereal in Linux, OptiView Series II (by Fluke Networks).