communications Flashcards
define network
is the exchange of information and ideas among people with a common profession or special interest.
define internet
a global network providing communication facilities.
network more
when two or systems are connected through wire or wireless
name and describe the advantages of using network
file sharing :users can share files with other users
hardware sharing: users can shore hardwares such as printers.
software sharing: users can shore software applications.
communication: users can send mail or chat,
disadvantages of using network:
cost:additional equipment would be required
management:ntechnetwork requires management from technical stuff.
malware: virus can easily spread through improperty
secured network.
hacking:once a divice is connected to another device,itis easier tack.
two types of network
LAN ,WAN
define network
when two or more systems are connected through wire or wireless
define local area network
a network connecting computers in a single room, in a single building
define WAN
a network connecting computer on different sites, possibly thousands of kilometers apart.
draw (1)client server (2)peer to peer
search google
define server
a server is a computer or system that provides resources, data to other computer known as clients
eg:
file server
print server
proxy server
web server
application server
what is meant by a client-server model of networked computers?
– at least one computer used to “serve”
–other computer are referred to as ‘client’
–other computer are referred to as “client”.
–server provides services/application
*downloading a file from a website is an example of a client-server application .
what is meant by the term client-server?
–the file is made available from web server
–the users browser is the client software
–the client (software browser) requests the file from the server
–the desired file is returned to the client computer
*bank has a client-server model of networked computers
describe using the bank as an example the key features of a client -server model?
–the bank’s server holds the customer account data
–and performs the requested task
–the computer used by the customers are the clients
– that send requests to the server
–which returns the results of the request
–e.g a customer asks for a list of recent transactions on their account.
how client server model enables the employees to access same files from different computers?
– the employees computers are the client
– the server hosts the shared file
– an employee can request a file (from the server) from any of the client computers
–several employees can access the same file (on the server)at the same time
benefit of client server
– files and resources are centralized (controlled by organization)
–creation of security/manage of security
– centralized back up (process that involves replicating data to server)
–internet monitoring
–clients can less powerful machines, therefore less expensive to buy
–saving resources on server reduces the burden on the client
describe the key features of peer to peer network?
–all computers are of equal status
–each computer provides access to resources and data
–computers can communicate and share resources
– each computer is responsible for its own security
benefits of peer to peer
–it avoids possibility of congestion when more clients are simultaneously requesting to download a file
–it allows user to download different parts of files separately.
– the parts are available from more than one host
describe drawbacks of peer to peer
–reduced security,each computer is at risk from viruses from other computer
–co central management of backup, if the data from one computer is not backed up it is lost to all of them.
–no central management of file, consistency may be difficult to maintain
–individual computers may respond slower because they are being accessed by other computers
