Q.
What is a LAN?
LAN is short for Local Area
Network. It refers to the connection between computers and other network
devices that are located within a small physical location.
Q.
What is a node?
A node refers to a point or joint
where a connection takes place. It can be computer or device that is part of a
network. Two or more nodes are needed in order to form a network connection.
Q.
What are routers?
Routers can connect two or more
network segments. These are intelligent network devices that store information
in its routing table such as paths, hops and bottlenecks. With this info, they
are able to determine the best path for data transfer. Routers operate at the
OSI Network Layer.
Q.
What is point to point link?
It refers to a direct connection
between two computers on a network. A point to point connection does not need
any other network devices other than connecting a cable to the NIC cards of
both computers.
Q.What
is anonymous FTP?
Anonymous FTP is a way of
granting user access to files in public servers. Users that are allowed access
to data in these servers do not need to identify themselves, but instead log in
as an anonymous guest.
Q.What
is subnet mask?
A subnet mask is combined with an
IP address in order to identify two parts: the extended network address and the
host address. Like an IP address, a subnet mask is made up of 32 bits.
Q.
What is the maximum length allowed for a UTP cable?
A single segment of UTP cable has
an allowable length of 90 to 100 meters. This limitation can be overcome by
using repeaters and switches.
Q.
What is data encapsulation?
Data encapsulation is the process
of breaking down information into smaller manageable chunks before it is
transmitted across the network. It is also in this process that the source and
destination addresses are attached into the headers, along with parity checks.
Q.
Describe Network Topology
Network Topology refers to the
layout of a computer network. It shows how devices and cables are physically
laid out, as well as how they connect to one another.
Q.
What is VPN?
VPN
means Virtual Private Network, a technology that allows a secure tunnel to be
created across a network such as the Internet. For example, VPNs allow you to
establish a secure dial-up connection to a remote server
Q.
Briefly describe NAT.
NAT is Network Address
Translation. This is a protocol that provides a way for multiple computers on a
common network to share single connection to the Internet.
Q.
What is the job of the Network Layer under the OSI reference model?
The Network layer is responsible
for data routing, packet switching and control of network congestion. Routers
operate under this layer.
Q.
How does a network topology affect your decision in setting up a network?
Network topology dictates what
media you must use to interconnect devices. It also serves as basis on what
materials, connector and terminations that is applicable for the setup.
Q.
What is RIP?
RIP, short for Routing
Information Protocol is used by routers to send data from one network to
another. It efficiently manages routing data by broadcasting its routing table
to all other routers within the network. It determines the network distance in
units of hops.
Q.
What are different ways of securing a computer network?
There are several ways to do
this. Install reliable and updated anti-virus program on all computers. Make
sure firewalls are setup and configured properly. User authentication will also
help a lot. All of these combined would make a highly secured network.
Q.
What is NIC?
NIC is short for Network
Interface Card. This is a peripheral card that is attached to a PC in order to
connect to a network. Every NIC has its own MAC address that identifies the PC
on the network.
Q.
What is WAN?
WAN stands for Wide Area Network.
It is an interconnection of computers and devices that are geographically
dispersed. It connects networks that are located in different regions and
countries.
Q.
What is the importance of the OSI Physical Layer?
The physical layer does the
conversion from data bits to electrical signal, and vice versa. This is where
network devices and cable types are considered and setup.
Q.
How many layers are there under TCP/IP?
There are four layers: the
Network Layer, Internet Layer, Transport Layer and Application Layer.
Q.
What are proxy servers and how do they protect computer networks?
Proxy servers primarily prevent
external users who identifying the IP addresses of an internal network. Without
knowledge of the correct IP address, even the physical location of the network
cannot be identified. Proxy servers can make a network virtually invisible to
external users.
Q.
What is the function of the OSI Session Layer?
This layer provides the protocols
and means for two devices on the network to communicate with each other by
holding a session. This includes setting up the session, managing
information exchange during the session, and tear-down process upon termination
of the session.
Q.
What is a Link?
A link refers to the connectivity
between two devices. It includes the type of cables and protocols used in order
for one device to be able to communicate with the other.
Q.
What are the layers of the OSI reference model?
There are 7 OSI layers: Physical
Layer, Data Link Layer, Network Layer, Transport Layer, Session Layer,
Presentation Layer and Application Layer.
Q.
What is backbone network?
A backbone network is a
centralized infrastructure that is designed to distribute different routes and
data to various networks. It also handles management of bandwidth and various
channels.
Q.
What is the importance of implementing a Fault Tolerance System? Are there
limitations?
A fault tolerance system ensures
continuous data availability. This is done by eliminating a single point of
failure. However, this type of system would not be able to protect data in some
cases, such as in accidental deletions.
Q.
What does 10Base-T mean?
The 10 refers to the data
transfer rate, in this case is 10Mbps. The word Base refers to base band, as
oppose to broad band. T means twisted pair, which is the cable used for that
network.
Q.
What is a private IP address?
Private IP addresses are assigned
for use on intranets. These addresses are used for internal networks and are
not routable on external public networks. These ensures that no conflicts are
present among internal networks while at the same time the same range of
private IP addresses are reusable for multiple intranets since they do not
“see” each other.
Q.
What is NOS?
NOS,
or Network Operating System, is specialized software whose main task is to
provide network connectivity to a computer in order for it to be able to
communicate with other computers and connected devices.
Q.
What is DoS?
DoS, or Denial-of-Service attack,
is an attempt to prevent users from being able to access the internet or any
other network services. Such attacks may come in different forms and are done
by a group of perpetuators. One common method of doing this is to overload the
system server so it cannot anymore process legitimate traffic and will be
forced to reset.
Q.
What is OSI and what role does it play in computer networks?
OSI (Open Systems Interconnect)
serves as a reference model for data communication. It is made up of 7 layers,
with each layer defining a particular aspect on how network devices connect and
communicate with one another. One layer may deal with the physical media used,
while another layer dictates how data is actually transmitted across the
network.
Q.
What is the purpose of cables being shielded and having twisted pairs?
The main purpose of this is to
prevent crosstalk. Crosstalks are electromagnetic interferences or noise that
can affect data being transmitted across cables.
Q.
What is the advantage of address sharing?
By using address translation
instead of routing, address sharing provides an inherent security benefit.
That’s because host PCs on the Internet can only see the public IP address of
the external interface on the computer that provides address translation and
not the private IP addresses on the internal network.
Q.
What are MAC addresses?
MAC, or Media Access Control,
uniquely identifies a device on the network. It is also known as physical
address or Ethernet address. A MAC address is made up of 6-byte parts.
Q.
What is the equivalent layer or layers of the TCP/IP Application layer in terms
of OSI reference model?
The TCP/IP Application layer
actually has three counterparts on the OSI model: the Session layer,
Presentation Layer and Application Layer.
Q.
How can you identify the IP class of a given IP address?
By looking at the first octet of
any given IP address, you can identify whether it’s Class A, B or C. If the
first octet begins with a 0 bit, that address is Class A. If it begins with
bits 10 then that address is a Class B address. If it begins with 110, then
it’s a Class C network.
Q.
What is the main purpose of OSPF?
OSPF, or Open Shortest Path
First, is a link-state routing protocol that uses routing tables to determine
the best possible path for data exchange.
Q.
What are firewalls?
Firewalls serve to protect an
internal network from external attacks. These external threats can be hackers
who want to steal data or computer viruses that can wipe out data in an
instant. It also prevents other users from external networks from gaining
access to the private network.
Q.
Describe star topology
Star topology consists of a
central hub that connects to nodes. This is one of the easiest to setup and
maintain.
Q.
What are gateways?
Gateways provide connectivity
between two or more network segments. It is usually a computer that runs the
gateway software and provides translation services. This translation is a key
in allowing different systems to communicate on the network.
Q.
What is the disadvantage of a star topology?
One major disadvantage of star
topology is that once the central hub or switch get damaged, the entire network
becomes unusable.
Q.
What is SLIP?
SLIP, or Serial Line Interface
Protocol, is actually an old protocol developed during the early UNIX days.
This is one of the protocols that are used for remote access.
Q.
Give some examples of private network addresses.
10.0.0.0 with a subnet mask of
255.0.0.0
172.16.0.0 with subnet mask of 255.240.0.0
192.168.0.0 with subnet mask of 255.255.0.0
Q.
What is tracert?
Tracert is a Windows utility
program that can used to trace the route taken by data from the router to the
destination network. It also shows the number of hops taken during the entire
transmission route.
Q.
What are the functions of a network administrator?
A network administrator has many
responsibilities that can be summarize into 3 key functions: installation of a
network, configuration of network settings, and maintenance/troubleshooting of
networks.
Q.
Describe at one disadvantage of a peer to peer network.
When you are accessing the
resources that are shared by one of the workstations on the network, that
workstation takes a performance hit.
Q.
What is Hybrid Network?
A hybrid network is a network
setup that makes use of both client-server and peer-to-peer architecture.
Q.
What is DHCP?
DHCP is short for Dynamic Host
Configuration Protocol. Its main task is to automatically assign an IP address
to devices across the network. It first checks for the next available address
not yet taken by any device, then assigns this to a network device.
Q.
What is the main job of the ARP?
The main task of ARP or Address
Resolution Protocol is to map a known IP address to a MAC layer address.
Q.
What is TCP/IP?
TCP/IP is short for Transmission
Control Protocol / Internet Protocol. This is a set of protocol layers that is
designed to make data exchange possible on different types of computer
networks, also known as heterogeneous network.
Q.
What protocol can be applied when you want to transfer files between different
platforms, such between UNIX systems and Windows servers?
Use FTP (File Transfer Protocol)
for file transfers between such different servers. This is possible because FTP
is platform independent.
Q.
What is the use of a default gateway?
Default gateways provide means
for the local networks to connect to the external network. The default gateway
for connecting to the external network is usually the address of the external
router port.
Q.
One way of securing a network is through the use of passwords. What can be
considered as good passwords?
Good passwords are made up of not
just letters, but by combining letters and numbers. A password that combines
uppercase and lowercase letters is favorable than one that uses all upper case
or all lower case letters. Passwords must be not words that can easily be
guessed by hackers, such as dates, names, favorites, etc. Longer passwords are
also better than short ones.
Q.
What is the proper termination rate for UTP cables?
The proper termination for
unshielded twisted pair network cable is 100 ohms.
Q.
What is netstat?
Netstat is a command line utility
program. It provides useful information about the current TCP/IP settings of a
connection.
Q.
What is the number of network IDs in a Class C network?
For a Class C network, the number
of usable Network ID bits is 21. The number of possible network IDs is 2 raised
to 21 or 2,097,152. The number of host IDs per network ID is 2 raised to 8
minus 2, or 254.
Q.
What happens when you use cables longer than the prescribed length?
Cables that are too long would
result in signal loss. This means that data transmission and reception would be
affected, because the signal degrades over length.
Q.
What common software problems can lead to network defects?
Software related problems can be
any or a combination of the following:
– client server problems
– application conflicts
– error in configuration
– protocol mismatch
– security issues
– user policy and rights issues
Q.
What is ICMP?
ICMP is Internet Control Message
Protocol. It provides messaging and communication for protocols within the
TCP/IP stack. This is also the protocol that manages error messages that are
used by network tools such as PING.
60)
What is Ping?
Ping is a utility program that
allows you to check connectivity between network devices on the network. You
can ping a device by using its IP address or device name, such as a computer
name.
Q.
What is peer to peer?
Peer to peer are networks that
does not reply on a server. All PCs on this network act as individual
workstations.
Q.
What is DNS?
DNS is Domain Name System. The
main function of this network service is to provide host names to TCP/IP
address resolution.
Q.
What advantages does fiber optics have over other media?
One major advantage of fiber
optics is that is it less susceptible to electrical interference. It also
supports higher bandwidth, meaning more data can be transmitted and received.
Signal degrading is also very minimal over long distances.
Q.
What is the difference between a hub and a switch?
A hub acts as a multiport
repeater. However, as more and more devices connect to it, it would not be able
to efficiently manage the volume of traffic that passes through it. A switch
provides a better alternative that can improve the performance especially when
high traffic volume is expected across all ports.
Q.
What are the different network protocols that are supported by Windows RRAS
services?
There are three main network
protocols supported: NetBEUI, TCP/IP, and IPX.
Q.
What are the maximum networks and hosts in a class A, B and C network?
For Class A, there are 126
possible networks and 16,777,214 hosts
For Class B, there are 16,384 possible networks and 65,534 hosts
For Class C, there are 2,097,152 possible networks and 254 hosts
Q.
What is the standard color sequence of a straight-through cable?
orange/white, orange,
green/white, blue, blue/white, green, brown/white, brown.
Q.
What protocols fall under the Application layer of the TCP/IP stack?
The following are the protocols
under TCP/IP Application layer: FTP, TFTP, Telnet and SMTP.
Q.
You need to connect two computers for file sharing. Is it possible to do this
without using a hub or router?
Yes, you can connect two
computers together using only one cable. A crossover type cable can be use in
this scenario. In this setup, the data transmit pin of one cable is connected
to the data receive pin of the other cable, and vice versa.
Q.
What is ipconfig?
Ipconfig is a utility program
that is commonly used to identify the addresses information of a computer on a
network. It can show the physical address as well as the IP address.
Q.
What is the difference between a straight-through and crossover cable?
A straight-through cable is used
to connect computers to a switch, hub or router. A crossover cable is used to
connect two similar devices together, such as a PC to PC or Hub to hub.
Q.
What is client/server?
Client/server is a type of
network wherein one or more computers act as servers. Servers provide a centralized
repository of resources such as printers and files. Clients refers to
workstation that access the server.
Q.
Describe networking.
Networking refers to the inter
connection between computers and peripherals for data communication. Networking
can be done using wired cabling or through wireless link.
Q.
When you move the NIC cards from one PC to another PC, does the MAC address
gets transferred as well?
Yes, that’s because MAC addresses
are hard-wired into the NIC circuitry, not the PC. This also means that a PC
can have a different MAC address when the NIC card was replace by another one.
Q.
Explain clustering support
Clustering support refers to the
ability of a network operating system to connect multiple servers in a
fault-tolerant group. The main purpose of this is the in the event that one
server fails, all processing will continue on with the next server in the
cluster.
Q.
In a network that contains two servers and twenty workstations, where is the
best place to install an Anti-virus program?
An anti-virus program must be
installed on all servers and workstations to ensure protection. That’s because
individual users can access any workstation and introduce a computer virus when
plugging in their removable hard drives or flash drives.
Q.
Describe Ethernet.
Ethernet is one of the popular
networking technologies used these days. It was developed during the early
1970s and is based on specifications as stated in the IEEE. Ethernet is used in
local area networks.
Q.
What are some drawbacks of implementing a ring topology?
In case one workstation on the
network suffers a malfunction, it can bring down the entire network. Another
drawback is that when there are adjustments and reconfigurations needed to be
performed on a particular part of the network, the entire network has to be
temporarily brought down as well.
Q.
What is the difference between CSMA/CD and CSMA/CA?
CSMA/CD, or Collision Detect,
retransmits data frames whenever a collision occurred. CSMA/CA, or Collision
Avoidance, will first broadcast intent to send prior to data transmission.
Q.
What is SMTP?
SMTP is short for Simple Mail
Transfer Protocol. This protocol deals with all Internal mail, and provides the
necessary mail delivery services on the TCP/IP protocol stack.
Q.
What is multicast routing?
Multicast routing is a targeted
form of broadcasting that sends message to a selected group of user, instead of
sending it to all users on a subnet.
Q.
What is the importance of Encryption on a network?
Encryption is the process of
translating information into a code that is unreadable by the user. It is then
translated back or decrypted back to its normal readable format using a secret
key or password. Encryption help ensure that information that is intercepted
halfway would remain unreadable because the user has to have the correct
password or key for it.
Q.
How are IP addresses arranged and displayed?
IP addresses are displayed as a
series of four decimal numbers that are separated by period or dots. Another
term for this arrangement is the dotted decimal format. An example is
192.168.101.2
Q.
Explain the importance of authentication.
Authentication is the process of
verifying a user’s credentials before he can log into the network. It is
normally performed using a username and password. This provides a secure means
of limiting the access from unwanted intruders on the network.
Q.
What do mean by tunnel mode?
This is a mode of data exchange
wherein two communicating computers do not use IPSec themselves. Instead, the
gateway that is connecting their LANs to the transit network creates a virtual
tunnel that uses the IPSec protocol to secure all communication that passes
through it.
Q.
What are the different technologies involved in establishing WAN links?
Analog connections – using
conventional telephone lines; Digital connections – using digital-grade
telephone lines; switched connections – using multiple sets of links between
sender and receiver to move data.
Q.
What is one advantage of mesh topology?
In the event that one link fails,
there will always be another available. Mesh topology is actually one of the
most fault-tolerant network topology.
Q.
When troubleshooting computer network problems, what common hardware-related
problems can occur?
A large percentage of a network
is made up of hardware. Problems in these areas can range from malfunctioning
hard drives, broken NICs and even hardware startups. Incorrectly hardware
configuration is also one of those culprits to look into.
Q.
What can be done to fix signal attenuation problems?
A common way of dealing with such
a problem is to use repeaters and hub, because it will help regenerate the
signal and therefore prevent signal loss. Checking if cables are properly
terminated is also a must.
Q.
How does dynamic host configuration protocol aid in network administration?
Instead of having to visit each
client computer to configure a static IP address, the network administrator can
apply dynamic host configuration protocol to create a pool of IP addresses
known as scopes that can be dynamically assigned to clients.
Q.
Explain profile in terms of networking concept?
Profiles are the configuration
settings made for each user. A profile may be created that puts a user in a
group, for example.
Q.
What is sneakernet?
Sneakernet is believed to be the
earliest form of networking wherein data is physically transported using
removable media, such as disk, tapes.
Q.
What is the role of IEEE in computer networking?
IEEE, or the Institute of
Electrical and Electronics Engineers, is an organization composed of engineers
that issues and manages standards for electrical and electronic devices. This
includes networking devices, network interfaces, cablings and connectors.
Q.
What protocols fall under the TCP/IP Internet Layer?
There are 4 protocols that are
being managed by this layer. These are ICMP, IGMP, IP and ARP.
Q.
When it comes to networking, what are rights?
Rights refer to the authorized
permission to perform specific actions on the network. Each user on the network
can be assigned individual rights, depending on what must be allowed for that
user.
Q.
What is one basic requirement for establishing VLANs?
A VLAN is required because at
switch level there is only one broadcast domain, it means whenever new user is
connected to switch this information is spread throughout the
network. VLAN on switch helps to create separate broadcast domain at
switch level. It is used for security purpose.
Q.
What is IPv6?
IPv6 , or Internet Protocol
version 6, was developed to replace IPv4. At present, IPv4 is being used to control
internet traffic, butis expected to get saturated in the near future. IPv6 was
designed to overcome this limitation.
Q.
What is RSA algorithm?
RSA is short for
Rivest-Shamir-Adleman algorithm. It is the most commonly used public key
encryption algorithm in use today.
Q.
What is mesh topology?
Mesh topology is a setup wherein
each device is connected directly to every other device on the network.
Consequently, it requires that each device have at least two network
connections.
Q.
what is the maximum segment length of a 100Base-FX network?
The maximum allowable length for
a network segment using 100Base-FX is 412 meters. The maximum length for the
entire network is 5 kilometers.
