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Posts Tagged ‘Images’

OSI Reference Model – Easy way to remember

In Bookmarks on November 27, 2006 at 11:24 am

 

osi-reference-model.JPG

 

Application Layer: End user processes like file transfer, e-mail, network software services. E.g. Telnet, FTP

 

Presentation/Syntax Layer: Format, Encrypt data to send across network.

 

Session Layer: Establishes, manages and terminates connections between applications .

 

Transport Layer: End-to-end error recovery, flow control.

 

Network Layer: Switching, Routing, Addressing, internetworking, error handling, congestion control and packet sequencing.

 

Data Link Layer: Encoding, decoding data packets into bits.

Media Access Control Sub-layer: Data access/transmit permissions.

Logical Link Sub-layer: Frame synchronization, flow control, error checking.

 

Physical Layer: Conveys the bit stream (electrical, light, radio)

E.g. Ethernet, RS232, ATM

 

An easy way to remember : use the following quotes

“All People Seem To Need Data Processing”

“People Do Not Trust Sales People Always”

Einstein’s Quote

In Uncategorized on November 22, 2006 at 9:03 am

einstein.jpg

Make one like this one here

http://www.hetemeel.com/einsteinform.php

Eye Diagram

In Uncategorized on November 22, 2006 at 8:45 am

eye-diagram.JPG
By super-imposing the transition patterns of a signal for 011, 001, 100, 110,
we get an Eye-Diagram. This is used to study Jitter, Voltage swing and Transition time.
The above diagram shows perfect one, practical one respectively.

Harmonics

In Uncategorized on November 22, 2006 at 8:01 am

harmonics.JPG

Legend : Signal

Dark red: Square wave of amplitude 1

Light red : sin wt

Blue: (1/3)sin 3wt Third Harmonic

Green: (1/5)sin 5wt Fifth Harmonic