25-02-2013, 11:34 AM
Current Trends in Information Technology
Current Trends.ppt (Size: 179 KB / Downloads: 116)
Learning Outcomes:
On successful completion of the unit the students should be able to:
develop a web site using a web site authoring package
use scripts to develop dynamic web pages
understand some of the basic principles and jargon
associated with some of the following topics
information retrieval
knowledge processing
software agents
object technology
multimedia information handling
communications and networks
Telecommunications and Networks
World telecommunications network
Largest man-made system
Technology and services evolving
rapidly
Facilities for linking computers
Data volumes increasing
Data transfer rates increasing
Multimedia systems (text/images/speech/video)
require high bandwidth
Broadcast Networkse.g. Ethernet
Any computer on the net can send a message at any time
message contains destination address
Each computer checks all messages and picks up its own
messages can collide and become garbled
Sending systems detect this and rebroadcast after a random
short time
If traffic is high, extra collision traffic may saturate the network
The Internet
Loosely administered network of networks
Agreed procedures for access and intercommunication
Internetworking uses gateways, routers and firewalls
Gateways: convert data traffic from one network format to another. They link LANs to WANs and WANs to WANs
Firewalls
Used to protect local networks or individual computers by implementing access controls to and from the internet
all traffic coming in or going out must pass through it
only authorised traffic gets through
Client Server Model
Clients and servers are software processes which are really two halves of the same application
The world wide web uses a client server model
Browsers are clients… send request to web servers for documents
Remote web server software receives the request for a document, retrieves it and sends to client