Networking Interview Questions
Explain about DNS?
DNS – Domain Name System. DNS is the Naming System for the resources over Internet; includes Physical nodes and Applications. DNS –It is the easy way to locate to a resource easily over a network and serves to be an essential component necessary for the working of Internet.
What is a Network?
A network means a set of devices that connected by physical media links. A network is recursively a connection of more than two nodes by a physical link or two or more networks connected by one or more nodes.
What is Bandwidth?
Each and Every Signal often has a limit of an upper range and lower range of frequency of signal it can carry. So this range of limit of network between its upper frequency and lower frequency is termed as Bandwidth.
List the criteria to check the network reliability?
A network Reliability is measured by the following factors.
- a) Downtime is the time it takes to recover.
- b) Failure Frequency is the frequency when it fails to work the way it is intended.
Define a Link?
At the basic level, a network includes two or more computers directly connected by some physical medium such as co-axial cable or optical fiber. And that physical medium is called a Link.
What is the DNS forwarder?
DNS servers usually communicate with outside DNS servers of the local network. A forwarder is an entry that is used when a DNS server receives DNS queries that it cant resolve locally. And then it forwards those requests to external DNS servers for resolution
A network consist of two or more computers which will be directly connected by some physical medium such as coaxial cable or optical fiber. And that physical medium is called as Links and the computer it connects is termed as Nodes.
What is a gateway or Router?
A router or gateway is a node that is connected to two or more networks. In general it forwards message from one network to another.
What is point-point link?
If the physical links are limited to a pair of nodes then it is said to be point-point link
What is DHCP scope?
A scope is a range, or pool of IP addresses that can be leased to DHCP clients on a given subnet.
What is FQDN?
An FQDN – fully qualified domain name contains both the hostname and a domain name. FQDN is uniquely identifies a host within a DNS hierarchy.
What is MAC address? Does it have some link or something in common to Mac OS of Apple?
MAC – Media Access Control. MAC is the address of the device identified at Media Access Control Layer of Network Architecture. Similar to IP address MAC address is unique address, i.e., no two device can have same MAC address. MAC address is stored at the ROM Read Only Memory of the device.
MAC Address and Mac OS are two different things and it should not be confused with each other. Mac OS is a POSIX standard Operating System Developed upon FreeBSD used by Apple devices.
Explain about PAN, LAN, HAN, SAN, CAN, MAN, WAN, GAN.?
- a) PAN(Personal Area Network)
LAN is the connection of Computers a
HAN is LAN of Home which connects to homely devices ranging from a few personal computers, phone, fax and printers.
- d) SAN(Storage Area Network)
e) CAN(Campus Area
CAN is the connection of devices, printers, phones and accessories within a campus which Links to other departments of the organization within the same campus.
- f) MAN
- g) WAN(Wide Area Network)
GAN connects mobiles across the globe using satellites. What is POP3?
POP3 stands for Post Office Protocol Version3 (Current Version). POP is a protocol which listens on port 110 and is responsible for accessing the mail service on a client machine. POP3 works in two modes such as Delete Mode and Keep Mode.
- a)Delete Mode: A mail is deleted from the mailbox after successful retrieval.
- b)b) Keep Mode: The Mail remains Intact in the mailbox after successful retrieval.
- How will check IP address on 98
Start ==> Run ==> command ==> winipcfg
How will you make partition after installing windows?
My computer ==> right click ==> manage ==> disk management ==>
select free space ==> right click ==> New partition.
What is IP?
IP is a unique 32 bits software address of a node in a network.
What is private IP?
Three ranges of IP addresses have been reserved for private address and they are not valid for use on the Internet. If you want to access internet with these address you must have to use proxy server or NAT server (on normal cases the role of proxy server is played by your ISP.).If you do decide to implement a private IP address range, you can use IP addresses from any of the following classes:
Class A: 10.0.0.0 10.255.255.255
Class B: 172.16.0.0 172.31.255.255
Class C: 192.168.0.0 192.168.255.255
What is public IP address?
A public IP address is an address leased from an ISP that allows or enables direct Internet communication.
What is virtual path?
Along any transmission path from a given source to a given destination, a group of virtual circuits can be grouped together into what is called path.
What is virtual channel?
Virtual channel is normally a connection from one source to one destination, although multicast connections are also permitted. The other name for virtual channel is virtual circuit.
What are the benefits of OSI Reference Model?
It provides a framework for discussing network operations and design.
What is the difference between routable and non- routable protocols?
Routable protocols can work with a router and can be used to build large networks. Non-Routable protocols are also there which is designed to work on small, local networks and cannot be used with a router
What is MAU?
In token Ring, hub is called Multi station Access Unit (MAU).
Explain 5-4-3 rule?
In an Ethernet network, between any two points on the network, there can be no more than five network segments or four repeaters and of those five segments only three of segments can be populated.
What do you meant by “triple X” in Networks?
The function of PAD (Packet Assembler Disassembler) is described in a document known as X.3. The standard protocol has been defined between the terminal and the PAD, called X.28; another standard protocol exists between PAD and the network, called X.29. Altogether, these 3 recommendations are called “triple X”.
What is the difference between TFTP and FTP application layer protocols?
The Trivial File Transfer Protocol (TFTP) allows a local host to obtain files from a remote host but does not provide reliability or security. It uses the fundamental packet delivery services offered by UDP.
The File Transfer Protocol (FTP) is the standard mechanism provided by TCP / IP for copying a file from one host to another. It uses the services offered by TCP and so is reliable and secure. It establishes two connections (virtual circuits) between the hosts, one for data transfer and another for control information.
What is the minimum and maximum length of the header in the TCP segment and IP datagram?
The header should have a minimum length of 20 bytes and can have a maximum length of 60 bytes.
What is difference between ARP and RARP?
The address resolution protocol (ARP) is used to associate the 32 bit IP address with the 48 bit physical address, used by a host or a router to find the physical address of another host on its network by sending a ARP query packet that includes the IP address of the receiver.
The reverse address resolution protocol (RARP) allows a host to discover its Internet address when it knows only its physical address.
Define about ICMP?
ICMP is Internet Control Message Protocol, a network layer protocol of the TCP/IP suite used by hosts and gateways to send notification of datagram problems back to the sender. It uses the echo test / reply to test whether a destination is reachable and responding. It also handles both control and error messages.