1. Mr. Kunjan D Shinde
Assistant Professor
Department of Electronics and Communication Engineering
PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Data Link Control
Framing
Fixed Size framing
Variable size framing
Flow and Error Control
Protocols
Noiseless Channel and Noisy Channel
Simplest stop and wait ARQ
Stop and Wait Go back N ARQ (sliding window, )
Selective Repeat ARQ
HDLC
Modes of operation
HDLC frames

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
A frame in a character-oriented protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Byte stuffing and unstuffing

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
A frame in a bit-oriented protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Bit stuffing and unstuffing

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
The most important responsibilities of the data link layer are flow control and
error control. Collectively, these functions are known as data link control.
Flow Control
Flow control refers to a set of procedures used to restrict the amount of data
that the sender can send before waiting for acknowledgment.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Simplest Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender site Algorithm for Simplest Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
receiver site Algorithm for Simplest Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Flow diagram for Simplest Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Stop-and-Wait Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender site Algorithm for Stop-and-Wait Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Receiver site Algorithm for Stop-and-Wait Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Flow diagram for Stop-and-Wait Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Although the Stop-and-Wait Protocol gives us an idea of how to add flow
control, noiseless channels are nonexistent. We discuss three protocols in this
section that use error control.
In a Data Link Layer, at any time if a error is detected , then that specific frame
is retransmitted this process is call Automatic Repeat Request (ARQ)
The following are the protocols used in Noisy Channel
Stop-and-Wait Automatic Repeat Request
Go-Back-N Automatic Repeat Request
Selective Repeat Automatic Repeat Request

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Stop-and-Wait ARQ Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender-site algorithm for Stop-and-Wait ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender-site algorithm for Stop-and-Wait ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Receiver-site algorithm for Stop-and-Wait ARQ Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Flow diagram Stop-and-Wait ARQ Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Go back N ARQ Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender-site algorithm for Go back N ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Receiver-site algorithm for Go back N ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender-site algorithm for Go back N ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender-site algorithm for Go back N ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Receiver-site algorithm for Go back N ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Flow Diagram for Go back N Protocol

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Stop-and-Wait ARQ is a special case of Go-
Back-N ARQ in which the size of the send
window is 1.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Window format for Selective Repeat ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Window format for Selective Repeat ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Design for Selective Repeat ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
In Selective Repeat ARQ, the size of the sender and receiver window
must be at most one-half of 2m.
Sender-site algorithm for Selective Repeat ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender-site algorithm for Selective Repeat ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Sender-site algorithm for Selective Repeat ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Receiver-site algorithm for Selective Repeat ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
Design of piggybacking in Go-Back-N ARQ

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.
High-level Data Link Control (HDLC) is a bit-oriented
protocol for communication over point-to-point and
multipoint links.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.

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Mr. Kunjan D. Shinde, Asst. Professor, Dept. of
E&CE, PESITM Shivamogga.