Wednesday, March 16, 2011

Network Administrator Interview Questions with Answers!!!

1.What is a NIC?
Network Interface Card

2.What is a MAC Address?
MAC- Media Access Control .its a unique identifier defined for certain hardware/network adapters

3.When would you use a crosslink cable?
To link computers using this cable..You need to assign the static Ip if u need to

4.What are the main advantages and disadvantages of Fiber-Optic-based networks?
Adv:More efficient and quality of service is better.
Dis: Expensive, complicated

5.What is the difference between a Hub and a Switch?
Hub is device to connect two devices, switch is a network bridge which processes and routes data approirately over network layer of OSI Reference model

6.On which OSI layer can a router be found?
physical layer

7.What is CSMA/CD?
Carrier sense multiple access with collision detection

8.What is multicast?
to send data/info to group of computers using same network

9.What is Broadcast?
TO send data/info to all of the members of the network..( simple 176.16.255.255 for class B network)

10.What is the difference between TCP and UDP?
TCP-Transmission Control Protocol
UDP- user Datagram protocol

UDP is user assisted program and converts the application into the encapsulated form and makes it end point for data to send and then TCP helps in transmission or broadcast!


11.Describe some of the settings that are added by TCP and by UDP to the packet's header.

ans:Its called Encapsulation

12.What are TCP Ports? Name a few.
As described above End points are called Ports.
5/TCP,UDP   Remote Job Entry
7/TCP,UDP   Echo

13.What is a TCP Session?
the layer that establishes ,manages and terminates the session between two communticating devices

14.What three elements make up a socket?

Protocol (TCP, UDP or raw IP).
Local socket address (Local IP address and port number)
Remote socket address

15.What will happen if you leave the default gateway information empty while manually configuring TCP/IP?
i think it will automatically get it from DNS server

16.What will happen if you execute the following command: "arp –d *"?
- deletes all the ip address information

17.What is ICMP?
Internet Control Message Protocol

18.When would you use the ping command with the "-t" switch?
to get the ping back from other computer with no packet loss

19.What command-line tool would help you discover for which port numbers your computer is listening?
netstat -n  (on Dos prompt)

20.What is APIPA? How would you recognize it?
Automatic Private IP Addressing
for small network if u see something default automatic numeric values entered in a device that is attached you can see someone novice has done that using APIPA

21.What is a Cyclic Redundancy Check?
its a function that checks the input data value/length and than produces the output usualy of integral of 32 bits

22.What would you type in at a command prompt to view the IP settings for the computer that you are sitting at?
"ipconfig"


23.What command would you type in at a command prompt to view the IP address of the remote computer?
Ping
Netstat

24.What is the W Value for class B?

25.What is the Net ID of an IP Address of 18.9.25.3 with Subnet Mask of 255.0.0.0?
CLASS A network with NET ID 18.0.0.0

26.What is CIDR?
Classless Inter-Domain Routing

27.What is 255.255.255.255 used for?
Research

28.What is the maximum number of hosts for a Class B Network?
16384 (2(raise to power N)- 2)

29.What is the (default) class type of 195.152.12.1?
CLASS B with NET ID 195.152.0.0

30.What is the subnet mask for 10.0.10.1/17?
255.0.0.0

31.What is the result when changing from a subnet mask of 255.255.224.0 to a subnet mask of 255.255.240.0?
hmm..broadcast and binary address changes i guess

32.How can you access a shared folder from a remote computer? Name at least 3 methods.
-from ur pc my network place
- using a mapped drive
-Universal Naming Convention (UNC)

Thursday, March 10, 2011

List of computing and IT abbreviations

UNC               Universal Naming Convention
\\servername\shared name (It is used to access the shared folder)
MAC              Media Access Control
PDC                Primary Domain Controllers
BDC               Backup Domain Controllers
SMP               Symmetric Multi Processors
AMP              Asymmetric Multi Processing
EFS                Encrypted File System
FAT                File Allocation Table
HCL               Hardware Compatibility List
IIS                  Internet Information Service
LSA                Local Security Authority
MMC             Microsoft Management Console
OU                  Organizational Unit
RAS                Remote Access Service
RDP                Remote Desktop Protocol (used for Terminal Services)
RRAS             Routing and Remote Access Service
SID                 Security Identifier
WINS             Windows Internet Name Service
GUID              Globally Unique identifier
IAS                 Internet Authentication Service
UPN                User Principle Name (Username@domainname.com)
BIOS               Basic Input Output System
Net BIOS        Network Basic Input/Output System
ARP                Address Resolution Protocol
DVD               Digital Video Disk
GPO                Group Policy Object (LGPO Local Group Policy Object)
IPsec               Internet Protocol Security
ISP                  Internet Service Provider
NAT               Network Address Translation
MBT               Master Boot Record
USB                Universal Serial Bus
POST              Power On Self Test
SCSI               Small Computer System Interface
SMTP             Simple Mail Transfer Protocol
URL               Uniform Resource Locator
RAID              Redundant Array of Independent Disk
IDE                 Intelligent drive Electronics or Integrated Drive Electronics
FQDN             Fully Qualified Domain Name (full computer name) [computername.domainname.com]
OSPF              Open Shortest Path First (these two are routing protocols)
RIP                 Routing Information Protocol
POP3              Post Office Protocol   (used to receive the mails)
SMTP             Simple Mail Transfer Protocol (Used to send the mails)
SMPS             Switch Mode Power Supply
PING              Packet Internet Groper
VNC               Virtual Network Computing
EULA             End User License Agreement
CAL               Client Access License
TSCAL          Terminal Services Client Access License
UPS                Uninterruptible Power Supply
BIND              Berkeley Internet Name Domain
PXE                Pre boot eXecutable Environment
UDF                Uniqueness Database file
LDAP             Light weight Directory Access Protocol

ISDN              Integrated Services Digital Network

VLSM            Variable Length Subnet Mask
CIDR              Classless Inter Domain Routing
IGMP             Internet Group Management Protocol
FSMO             Flexible Single Master Operations     
APIPA            Automatic IP addressing
NetBEUI        Net Bios Enhanced User Interface
UDP                User Datagram Protocol
FTP                File Transfer Protocol
Mbps              Mega bits per second
Ntds.dit           Nt directory services.directory information tree.
ICMP             Internet Control message Protocol
IGMP             Internet group Management Protocol
NNTP             Network News Transfer Protocol
RADIUS        Remote Authentication Dial In User service
SNMP            Simple Network Management protocol
VPN               Virtual Private Network
L2TP              Layer2 Tunneling Protocol
PPTP              Point to Point Tunneling Protocol
ADSI             Active Directory Service Interfaces
SUS               Software Update Service
SMS              System Management Service
WUS             Windows Update service
TFTP             Trivial File Transfer Protocol


List of important port numbers

List of important port numbers

15        è        Netstat
21        è        FTP
23        è        Telnet
25        è        SMTP
42        è        WINS
53        è        DNS
67        è        Bootp
68        è        DHCP
80        è        HTTP
88        è        Kerberos
101      è        HOSTNAME
110      è        POP3
119      è        NNTP
123      è        NTP     (Network time protocol)
139      è        NetBIOS
161      è        SNMP
180      è        RIS
389      è        LDAP (Lightweight Directory Access Protocol)
443      è        HTTPS (HTTP over SSL/TLS)
520      è        RIP
79        è        FINGER
37        è        Time
3389    è        Terminal services
443      è        SSL (https) (http protocol over TLS/SSL)
220      è        IMAP3
3268    è        AD Global Catalog
3269    è        AD Global Catalog over SSL            
500      è        Internet Key Exchange, IKE (IPSec) (UDP 500)