Computer Networks – Formative Test
1. What is Computer Networks?
Computer Networks is a group of two or more computers connected together using a
telecommunication system for the purpose of communicating and sharing resources.
2. List types of Computer Network?
• Local Area Network (LAN)
The computers are geographically close together (in the same building). Usually used by
small organizations.
• Wide Area Network (WAN)
The computers are farther apart and are connected by Internet.
• Campus Area Network (CAN)
The computers are within a limited geographic area, e.g. campus and military base.
• Metropolitan Area Network (MAN)
A data network designed for town or city.
• Personal Area Network (PAN)
A network contained within a user’s home that connects a person’s digital device.
• Global Area Network (GAN)
A single network with connection points spread around the world.
3. What is topology? List down the type of topology.
The geometric arrangement of a computer system or devices on the network connects to
each other, either physically or logically. Some examples of topologies are;
-
Bus topology
Star topology
Ring topology
Mesh topology
Tree topology
Hybrid topology..etc.
4. What is a protocol; what is routable and non-routable protocol?
The protocol defines a common set of rules and signals that computers on the network
use to communicate. The three most popular protocol families are NetBEUI, IPX/SPX
and TCP/IP.
Routable protocol is defined as the protocol that carries the data over the network for
example IP, IPX.
Done by: Mohammad Hazizul Bin Hj. Abd Halim.
(CC/23/16/07)
Computer Networks – Formative Test
Non-routable protocol means that the servers and computers in the Internet, outside of the
localized, cannot resolve the routing protocol used or network attached ones.
5. What is half duplex, simple and full duplex?
Simplex – One-way communication
Data in a simplex is always one way. Simplex channels are not often used because it is
not possible to send back error or control signals to the transmit end.
Half Duplex – Two-way communication, one direction at a time (i.e. walkie-talkie)
A half duplex channel can send and receive but not at the same time (not simultaneously).
It is like a one-lane bridge where two-way traffic must give way in order to cross. Only
one end transmits at a time, the other end receives. In addition, it is possible to perform
error detection and request the sender to retransmit information that arrived corrupted.
Full Duplex – Two-way simultaneously communication (i.e. telephone)
Data can travel in both directions simultaneously. There is no need to switch from
transmit to receive mode like half duplex. It is like a two lane bridge on a two-lane
highway.
6. What are the Share and User Level?
Share level enables us to supply a password for each shared resource and User level
enables us to specify users and groups who have access to each shared resource.
7. What is TRACERT?
A Windows based command-line tool that can be use to trace the path that an Internet
Protocol (IP) packet takes to its destination from a source. Tracert will determine the path
taken to a destination.
8. What is NSLOOKUP?
A program that an Internet server administrator uses to find corresponding IP address and
do reverse name lookup and find the host name for an IP address you specify.
9. Which MS Windows OS cannot join to Domain?
Windows XP Home Edition because it does not comes with a file and printer sharing
service module.
10. What is DNS?
Done by: Mohammad Hazizul Bin Hj. Abd Halim.
(CC/23/16/07)
Computer Networks – Formative Test
A database system that translates a computer’s fully qualified domain name into an IP
address.
11. What is NetBIOS name?
NetBIOS stands for Network Basic Input/Output System. It is a program that allows
applications on different computers to communicate within a local area network (LAN).
NetBIOS provides network input/output services to support client/server applications on
a network.
12. What is WINS?
Windows Internet Naming Service resolves Windows network computer names to
Internet IP addresses, allowing Windows computers on a network to easily find and
communicate with each other.
13. What is DHCP?
Dynamic Host Configuration Protocol acts as a client/server protocol, which provide an
internet protocol host with its IP address and other configuration setting.
14. What cable do you use to link 2 computer together?
Cross Over” RJ45 network cable and Unshielded twisted pair (UTP) cable.
15. How to resolve MAC address to IP address?
Using MAC Address Resolver in the Address Monitoring then select an IP to enter a
MAC address then select Resolve and both MAC address and IP address results will be
shown.
16. How to make the website to be secure and encrypted?
By making use some of these server and applications that are Web (Apache), Database
(Oracle) and Proxy Server (Squid) and Web Application Server (Web logic) and some
Web Applications such as ASP, ASP.NET/. NET.
17. What is IP?
The Internet Protocol (IP) is a data-oriented protocol used for communicating data across
a packet-switched internetwork
18. What is ICMP?
ICMP (Internet Control Message Protocol) is a complementary protocol to IP
(Internet Protocol) which is designed for sending control and test messages across IP
networks. Like IP, ICMP resides on the Network Layer of the OSI Model.
19. I can send e-mail but I can’t receive e-mail. What's the problem?
Done by: Mohammad Hazizul Bin Hj. Abd Halim.
(CC/23/16/07)
Computer Networks – Formative Test
The problem is Internet Mail Access Protocol (IMAP) is incorrectly configured, or that
the firewalls program control settings changed, due to some new Windows update after
download of some security updates.
20. What is UDP?
User Datagram Protocol (UDP) is a TCP/IP transport layer protocol that supports
unreliable, connectionless communication between hosts on a TCP/IP network.
21. What is SSL?
Secure Sockets Layer (SSL), are cryptographic protocols that provide secure
communications on the Internet for such things as web browsing, e-mail, Internet faxing,
instant messaging and other data transfers.
22. What is HTTPS?
Https (Hypertext Transfer Protocol over Secure Socket Layer) is a URI scheme used to
indicate a secure HTTP connection. It is syntactically identical to the http:// scheme
normally used for accessing resources using HTTP.
23. What is APIPA?
Automatic Private IP Address (APIPA) is where a Windows computer can assign itself
an Internet Protocol (IP) address in the event that DHCP server is not available or does
not exist on the network. This feature makes configuring and supporting a small LAN
running TCP/IP less difficult.
24. What is IMAP?
Internet Message Access Protocol (IMAP) is an Internet standard protocol for storing and
retrieving messages from Simple Mail Transfer Protocol (SMTP) hosts.
25. What is RARP?
Reverse Address Resolution Protocol (RARP) is a network layer protocol used to obtain
an IP address for a given hardware address (such as an Ethernet address).
26. What is SNMP?
The Simple Network Management Protocol (SNMP) forms part of the Internet protocol
suite as defined by the Internet Engineering Task Force (IETF). SNMP is used in network
management systems to monitor network-attached devices for conditions that warrant
administrative attention. It consists of a set of standards for network management,
including an Application Layer protocol, a database schema, and a set of data objects.
27. What is peer-to-peer network?
Done by: Mohammad Hazizul Bin Hj. Abd Halim.
(CC/23/16/07)
Computer Networks – Formative Test
A peer-to-peer (P2P) network is where two or more PCs in a network are connected and
share resources without going through a separate server computer.
28. What is fat-client based network?
A fat client is a computer (client) in client-server architecture networks, which typically
provides rich functionality independently of the central server.
29. What is thin-client network?
Thin-client network is the terminal that does not have the ability to process information
independently which relies on servers for applications, data storages and administration.
30. What is speed of CAT 3 and CAT 5?
Speed of CAT 3 is 10Mbps meanwhile CAT 5 is 100Mbps.
31. List the connectors for fiber optic?
• ST (Single Terminus/Straight Tip – Stick and Twist)
• SC (Subscriber Connector – Stick and Click)
• FTC (Fiber Tight Connector) to hold fiber and cable to a wall or Lightbox. Fibers are
held in place by a twist of a nut
• P-Clips to hold the Fiber Cables from Sideglow to Endglow
• DNP (Dry-Non-Polished)
• DNP connector
32. What is HUB, MAU, BRIDGE and GATEWAYS?
HUB – It connects computers in or at the center or local point star topology. It used
single collision domains.
MAU (Medium Attachment Unit) – A small device that converts signals between an AIU
and a network cable such as 10Base5 or 10Base2.
BRIDGE – Can directs information flow on a network from one node to another. It was
prevalent before switches came into use.
GATEWAYS – Can be hardware and software translator that interprets and converts
protocols.
33. What is OSI layer?
The Open System Interconnection (OSI) model defined as a networking framework for
implementing protocols in seven layers.
-
Application Layer
Presentation Layer
Done by: Mohammad Hazizul Bin Hj. Abd Halim.
(CC/23/16/07)
Computer Networks – Formative Test
-
Session Layer
Transport Layer
Network Layer
Data Layer
Physical Layer
34. What is ASDL, CSU/DSU, Frame Relay, ISDN and Dial-Up?
ADSL (Asymmetric Digital Subscriber Line) shares ordinary telephone lines by using
frequencies above the voice band, but the higher frequencies interfere with regular
telephone usage.
CSU/DSU (Channel Service Unit/Data Service Unit) is a hardware device about the size
of an external modem that converts a digital data frame from the communications
technology used on a local area network (LAN) into a frame appropriate to a wide-area
network (WAN) and vice versa.
Frame Relay is a high-speed packet switching protocol used in wide area networks
(WANs). Providing a granular service of up to DS3 speed (45 Mbps).
ISDN (Integrated Services Digital Network) is an international standard for switched,
digital dial-up telephone service for voice and data. Analog telephones and fax machines
are used over ISDN lines, but the ISDN terminal adapter converts their signals into
digital
Dial-up refers to using the regular "dial-up" telephone network to send data from a
computer to a remote network or to a remote device. The computer's digital data are
converted to analog signals in the same frequency range as human voice by a modem.
At the other end, another modem converts the analog back to digital.
35. List down 802 IEEE standard. (12 of them)
i.
ii.
iii.
iv.
v.
vi.
vii.
viii.
ix.
x.
xi.
xii.
IEEE 802.1 Bridging (networking) and Network Management
IEEE 802.2 Logical link control
IEEE 802.3 Ethernet
IEEE 802.4 Token bus (disbanded)
IEEE 802.5 Defines the MAC layer for a Token Ring
IEEE 802.6 Metropolitan Area Networks (disbanded)
IEEE 802.7 Broadband LAN using Coaxial Cable (disbanded)
IEEE 802.8 Fiber Optic TAG (disbanded)
IEEE 802.9 Integrated Services LAN (disbanded)
IEEE 802.10 Interoperable LAN Security (disbanded)
IEEE 802.11 Wireless LAN & Mesh (Wi-Fi certification)
IEEE 802.12 demand priority
36. What is RAID? Explain RAID 1 and 5.
Done by: Mohammad Hazizul Bin Hj. Abd Halim.
(CC/23/16/07)
Computer Networks – Formative Test
RAID (Redundant Array of Independent Disks) is the disk subsystem that is used to
increase performance or provide fault tolerance or both.
RAID 1 - Fault Tolerance
Uses disk mirroring, which provides 100% duplication of data. Offers highest reliability,
but doubles storage cost. RAID 1 is widely used in business applications.
RAID 5 - Speed and Fault Tolerance
Data are striped across three or more drives for performance, and parity bits are used for
fault tolerance. The parity bits from two drives are stored on a third drive and are
interspersed with user data. RAID 5 is widely used in servers.
37. What is the difference between incremental and differential backup?
An incremental backup is a backup method where multiple backups are kept (not just the
last one). These backups will be incremental if each original piece of backed up
information is stored only once, and then successive backups only contain the
information that changed since a previous backup.
The advantage to this is the quicker recovery time, requiring only a full backup and the
latest differential backup to restore the system. The disadvantage is that for each day
elapsed since the last full back up, more data needs to be backed up, especially if a
majority of the data has been changed.
38. What is the port number of FTP, SMTP, and POP3?
File Transfer Protocol (FTP): port number is 21
Simple Mail Transfer Protocol (SMTP): port number is 25.
Post Office Protocol version 3 (POP3): port number is 110.
39. What is Data Encryption standard and Public-key Encryption?
Data Encryption Standard is a method of data encryption using a private (secret) key that
uses a 56-bit key and uses the block cipher method, which breaks text into 64-bit blocks
and then encrypts them.
Public-key Encryption is a cryptographic system that uses two keys to encrypt data, a
public key known to everyone and a private (secret) key known only to the recipient of
the message.
40. What is Viruses and other destructive programs?
Virus is a computer program that executes when an infected program is executed in
which only executed files having the extension .EXE, .COM, .BAT or .SYS can be
infected.
41. What are SLIP, PPP and PPTP?
Done by: Mohammad Hazizul Bin Hj. Abd Halim.
(CC/23/16/07)
Computer Networks – Formative Test
SLIP (Serial Line IP). A communications protocol for dial-up access to TCP/IP networks.
It was commonly used to gain access to the Internet as well as to provide dial-up access
between LANs.
PPP (Point-to-Point Protocol). The most popular method for transporting IP packets over
a serial link between the user and the ISP, which establishes the session between the
user's computer and the ISP using its own Link Control Protocol (LCP).
PPTP (Point-to-Point Tunneling Protocol) is a protocol from Microsoft that is used to
create a virtual private network (VPN) over the Internet. Remote users can access their
corporate networks via any ISP that supports PPTP on its servers.
42. What are TDR and Tone Generator?
A time-domain reflectometer (TDR) is an electronic instrument used to characterize and
locate faults in metallic cables (for example, twisted wire pairs, coaxial cables), OTDR
domain: optical fibers.
A tone generator is a type of signal generator optimized for use in audio and acoustics
applications. Tone generators typically include sine waves over the audio frequency
range (20 Hz–20 kHz).
Done by: Mohammad Hazizul Bin Hj. Abd Halim.
(CC/23/16/07)