Cramster.com - Homework Solutions, Lecture Notes, Exams, and Free Online Homework Help
Sign Up Now! Login Customer Support Cramster Blog
McAfee Secure sites help keep you safe from identity theft, credit card fraud, spyware, spam, viruses and online scams
Problem Solved.
    Home    
    Homework Help    
   Answer Board   
    Resources (Beta)    
   
You Are Here: Home > Answer Board > Computer Science > Topic: CS
Member's Topic Headline:

CS

Know the answer? Have a better solution? Share it.
Sign Up Now for FREE!
Join the thousands of students
getting ahead in their classes.
Member Testimonials

Question:

Advertisement:
Answer | Ask New Question | Customize Profile | Leaderboards | 
FAQ

Member's Avatar
Novice
Karma Points: 43
Respect (87%):
Date Posted: 7/22/2008 11:20:49 AM  Status: Live
CS
Course Textbook Chapter Problem
Networking Computer Networking: A Top Down Approach ,4th edition. Jim Kurose, Keith RossAddison-Wesley, July 2007. N/A N/A
Question Details:
 

2. Reliable Data Transfer

(a) Notice that when the sender of rdt3.0 receives a "duplicate ACK" for the last packet, this ACK is ignored. Suppose that instead, rdt3.0 implemented a version of Fast Retransmit and resent the packet whenever it received such an ACK. I.e. it would include the following transition rule in

state "Wait for ACK0":

rdtrcv(rcvpkt) && notcorrupt(rcvpkt) && isACK(rcvpkt,1)

udtsend(sendpkt), start timer

Show how with this modification, a single delayed ACK from the receiver can result in unnecessary retransmissions of subsequent packets.

 

Answers:

Cramster Expert

Member's Avatar
(Cramster SME)
Moderator
Cramster In-House Subject Matter Expert
Date Posted: 7/23/2008 12:45:42 AM  Status: Live
Asker's Rating: Helpful   
Response:
Dear,
 
  when the sender of rdt3.0 receives a "duplicate ACK" for the last packet.
  rdt3.0 implemented a version of Fast Retransmit and resent the packet whenever it received such  an ACK. I.e. it would include the following transition rule in  state "Wait for ACK0":
 
  
 
A single delayed ACK from the receiver can result in unnecessary retransmissions of subsequent packets.
 
swth's Comment:
Thank u so much ur answers are really helpful



By reading or posting messages on these forums, you are agreeing to the Answer Board's Terms of Service and Conduct (TSC).


About Cramster | Terms of Use | Privacy Policy | Contact Us | Press Room | Site Map | Support | Anti-Cheating Policy

Cramster.com is not affiliated with any publisher. Book covers, title and author names appear for reference only.
Copyright © 2008 Cramster, Inc.