Partner Link

Cheap Mobile Phones
- Cheap Mobile Phones - Best Mobile Phone Deals, Laptops, Sat Nav Devices, Cordless Phones, Internet Phones, Broadband Internet Deals from leading retailers of UK. Choose Products and Compare Prices for best deals.

||

Mobile Phones
- Offers mobile phones on contract, pay as you go, sim free deals with free gifts. We compare latest phone deals from leading retailers of UK.

. ||

Custom logo design
Get your company a logo design. Professional logo designs by expert logo designers. Call 0208 133 2514 for custom logo design packages.

||

Top Site

Flyer Printing Flyer Printing – Print your flyers on latest design. We offer cheap flyer printing services in all over UK. Full color flyer printing & art work in your own budget. Order for online flyer printing from your home.
Mobile Broadband Deals  Mobile Broadband - Buy Mobile Broadband Deals, Best Mobile Internet Offers With Free Line Rental, USB Modem and Cheapest Network Connection Offers from 3 Mobile in UK
Mobile Upgrades Upgrade Mobile Phone Deals – upgrade your mobile phones from o2, orange, virgin, vodafone, t-mobile and all Manufacturers Nokia, Samsung, Sony Ericsson, LG ,Blackberry and Motorola. Mobile Broadband Deals Mobile Broadband - Buy Mobile Broadband Deals, Best Mobile Internet Offers With Free Line Rental, USB Modem and Cheapest Network Connection Offers from 3 Mobile in UK.

PACKETS, FRAMES AND ERROR DETECTION

INTRODUCTION:
The previous chapters of data communication described how bits are transmitted
across a physical network using a transmission medium.
This chapter introduces the concept of packets of data rather than bits for
communication.

CONCEPT OF ‘PACKET’:
Network systems divide data in small blocks or junks called packets, which they
send individually. Why we need packets rather than bits? The answer to this question is
because a sender and receiver need to coordinate to detect transmission errors. Also the
individual connection between each pair of computers is not possible. That’s why to
solve these problems shard network connections are made among many workstations.

PROBLEMS WITH SHARING:
The demand of sharing is very high because many computers need to use the shared
networks. In addition to this some applications have large data transfer. In this way they
hold the network for long time. But on the other hand some applications cannot wait so
long. So we need a mechanism for fairness.

SOLUTION FOR FAIRNESS:
To the fairness, the solution is to divide the data into small block or chunks called
‘PACKETS’. Computers take turns to send one packet at a time over the shared
connection.
Because each packet is small so no computer experiences a long delay.
Example:
In the figure one reason for using the packets is illustrated. We see that in a shared
resource when one pair of computer communicates, the other must wait. To understand
the use of packet here, let’s suppose a transmission with packets in the figure.

WITHOUT PACKETS:
A 5MB file transferred across network with 56Kpbs capacity will require 12 minutes.
This means that all that computers will be forced to wait for 12 minutes before initiating

other transfers.WITH PACKETS:
Now if the file is broken into packets, other computers must only wait until packet (not
entire file) has been sent.
Suppose file is broken into 1000 byte packets.
Now each packet takes less than 0.2 seconds to transmit. Here other computers must only

wait for 0.14 sec before beginning to transmit.
Note: - if both files are 5MB long, each now takes 24 minutes to transmit. But if the
second file is 10MB long it sill be transmitted in only 2.8 seconds while 5MB file still
takes roughly 12 minutes.

PACKETS AND TDM:
Dividing data into small packets allow time division multiplexing. In TDM each packet
leaves the source and is switched on the shared communication channel through a
multiplexer. At the destination the packet is switched through a demultiplexer to the
destination.
In the figure this process is illustrated with a multiplexing circuit shown.

4 comments:

Anonymous said...

І abѕolutely love youг blog.. Very nicе coloгs & theme.
Did уou make this amazing site уouгѕelf?

Ρlease reply baсk as I'm attempting to create my own site and want to learn where you got this from or just what the theme is named. Kudos!
Here is my website ; ebusinessopportunities.net

Anonymous said...

Heya this is kind of оf off topic but I was wantіng to know if blοgs use
WYSIWΥG editors or if you havе to manually
code with HTML. I'm starting a blog soon but have no coding experience so I wanted to get advice from someone with experience. Any help would be greatly appreciated!
Also visit my page cars auction

Anonymous said...

I think that what you sаid was verу reasonable.
Hoωever, ωhat about this? what if уou wеre
tο create a awesome post tіtle? ӏ mean, I don't wish to tell you how to run your website, however suppose you added a headline that grabbed folk's attention?
Ι mеan "PACKETS, FRAMES AND ERROR DETECTION" is kіnda
vanillа. You cоuld pеek at Yahoo's home page and watch how they create news headlines to get people to open the links. You might add a video or a related pic or two to get readers interested about what you've got to say.
In my opіnion, it might maκe yоuг posts a lіttle
livelier.
Also visit my site - Woodworking

Anonymous said...

Its like you learn my thoughts! You appear to grasp
so much about this, such as you wrote the e-book in it or something.
I believe that you simply could do with some % to force the message house a bit, however other than that, that is great blog. An excellent read. I'll definitely be back.
Look at my page :: work online

Post a Comment

Thanks for interest it