Consider a simple protocol for transferring files over a link. Aftersome initial negotiation, A sends data packets of size 1 KB to B; Bthen replies with an acknowledgment. A always waits for eachACK before sending the next data packet; this is known asstop-and-wait. Packets that are overdue are presumed lost andare retransmitted.(a) In the absence of any packet losses or duplications, explainwhy it is not necessary to include any "sequence number"data in the packet headers.(b) Suppose that the link can lose occasional packets, but thatpackets that do arrive always arrive in the order sent. Is a2-bit sequence number (that is, N mod 4) enough for A and Bto detect and resend any lost packets? Is a 1-bit sequencenumber enough?(c) Now suppose that the link can deliver out of order and thatsometimes a packet can be delivered as much as 1 minuteafter subsequent packets. How does this change thesequence number requirements?

Stop-and-wait stop and wait, implies, that anything the information that the shipper needs to send,…

Consider a simple protocol for transferring files over a link. After some initial negotiation, A sends data packets of size 1 KB to B; B then replies with an acknowledgment. A always waits for each ACK before sending the next data packet; this is known as stop-and-wait. Packets that are overdue are presumed lost and are retransmitted.

Consider a simple protocol for transferring files over a link. After some initial negotiation, A sends data packets of size 1 KB to B; B then replies with an acknowledgment. A always waits for each ACK before sending the next data packet; this is known as stop-and-wait. Packets that are overdue are presumed lost and are retransmitted.

Principles of Information Security (MindTap Course List)

6th Edition

ISBN:9781337102063

Author:Michael E. Whitman, Herbert J. Mattord

Publisher:Michael E. Whitman, Herbert J. Mattord

Chapter6: Security Technology: Access Controls, Firewalls, And Vpns

Section: Chapter Questions

Problem 2RQ

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