DBMS

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ICT Classes for G.C.E. O/L and A/L Students in Trincomalee.

ICT Classes for G.C.E. O/L and  A/L Students in Trincomalee.

Classes will be started soon
for more details.... trinco2shankar@gmail.com
Mobile 0774822134

Network Questions

1)      Define data and singals.

2)      Briefly describe following characteristics of a sine wave.

a.       Amplitude

b.      Frequence

c.       Phase

3)  What is wave length?

4)      Explain the difference between Client-Server and Peer-to-Peer networks.

5)      Explain the  three main network topologies (i.e. bus, ring, star) and  list two                    

 advantages and two disadvantages of each of them.

6)      What is a protocol? Give two examples.

7)      State the function of each layer in OSI model.

8)      What are the two components of an IP adder?

9)      Explain the three main classes of IP.

10)  Briefly describe the functions of the following devices.

a.  Switch

b.  Router

c.  Hub

11)    Define following

a.       Computer security

b.      Network security

c.       Internet security

12)    Define followings

a.       Cryptography

b.      Plain text

c.       Cipher text

d.      Encryption

e.       decryption

f.       Key

g.       Symmetric keycryptography algorithms

h.      Asymmetric Key cryptography algorithms.

i.        Firewall

13)      What are the three types of keys in cryptography?

 Explain the difference between Client-Server and Peer-to-Peer networks.

Peer-to-Peer

Client-Server

·         Easy to install and configure. ·         No dedicated server required. ·         Users control their own resources. ·         Inexpensive to purchase and operate. ·         No specialist software required. ·         No dedicated administrator to run the network required. ·         Difficult to employ security. ·         Too many passwords for shared resources. ·         Backups difficult to manage. ·         No centralization. ·         Limited users.

·         Centralized user accounts, security and access controls simplify network administration. ·         More powerful equipment means more efficient access network resources. ·         Single password login, means access to all resources. ·         Supports greater numbers of users, or networks where resources are heavily used ·         More costly to install and maintain. ·         Single point of failure, server goes down, the network goes down. ·         Complex special-purpose software requires appointment of expert staff, increasing costs. ·         Dedicated hardware and software increases costs.

                                                                                           

           

          

What is the difference between port address logical address and physical address?

What is the difference between port address logical address and physical address?

Through logical address the system identify a network (source to destination). after identifying the network physical address is used to identify the host on that network. The port address is used to identify the particular application running on the destination machine. 

Logical Address: An IP address of the system is called logical address. This address is the combnation of Net ID and Host ID. This address is used by network layer to identify a particular network (source to destination) among the networks. This address can be changed by changing the host position on the network. So it is called logical address. 

Physical address: Each system having a NIC(Network Interface Card) through which two systems physically connected with each other with cables. The address of the NIC is called Physical address or mac address. This is specified by the manficture company of the card. This address is used by data link layer.