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If maximum sequence num is N then max window size is?

a) in case of selective repeat

b)in case of GBN
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sequence numbers for GBN start from 0 or 1??
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It is not fixed from where to start the sequence number

Whenever a host wants to send data it can choose any number in between 0 to 2^32 -1

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@ashwini
what i assumed is
they have given the maximum value of seq num as N not the maximum possible values
so assume max value is 7
then we can assume 0 ,1 ,2,3,4,5,6,7
which is totally 8 (i.e) N+1
so should be N+1/2 for selective repeat
correct me
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@Aish yes correct

If Max value of sequence no is N

SR : (N+1)/2

GBN : N

If maximum no of sequences are N

SR: N/2

GBN: N-1

If maximum sequence num is N ie the maximum values is given then:

In GBN : N

In SR : (N+1)/2

Ex : Given max seq num is 7, then

In GBN : MAX Window size of Sender : 7

MAX Window size of Receiver : 1

In SR : MAX Window size of Sender : (7+1)/2 = 4

MAX Window size of Receiver : (7+1)/2 = 4

(sequence number will count from 0-7 ie total 8)

If Number of sequences is N then:

In GBN : N-1

In SR : N/2

Ex: If number of sequences is 7, then

In GBN : MAX Window size of Sender : 6

MAX Window size of Receiver : 1

In SR : MAX Window size of Sender : (7)/2 = 3   (take floor)

MAX Window size of Receiver : (7)/2 = 3  (take floor)

As (Window size of Sender + Window size of Receiver) <= (Available Sequence Numbers)

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