ECE438-F11-midterm - ECE/CS 438 Midterm Exam Wednesday,...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
ECE/CS 438 Midterm Exam Wednesday, October 19 th , 2011 2:00pm – 3:00pm Name: 1) (5pts) Explain what is CIDR (cider) addressing and what is the main advantage over the original IPv4 specification? 2) (5pts) Name the four layers of the layered architecture of the Internet. physical, network layer, transport, application 3) (5pts) Why are ACKs better than only-NAKs in ARQ protocols? 4) (5pts) Explain what is the difference between frequency hopping and direct sequence transmission in wireless networks. 5) (6pts) A class B network 130.50.0.0 on the Internet has a subnet mask of 255.255.240.0. (a) What is the maximum number of hosts per subnet? (b) What is the IP address of the first host on the first subnet in this class B network? 6) (12pts) A host has a 2MB file to be sent to another host but it first needs to compress it. It takes 2sec of CPU time to compress it by 50% and 4sec to compress it by 60%. Compute the bandwidth at which each compression option takes the same amount of time to compress and transmit the file.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Name: 2 Without compression the total time is: 2MB/bandwidth. When we compress the file, the total time is:
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/08/2012 for the course ECE 438 taught by Professor Luo during the Fall '08 term at University of Illinois, Urbana Champaign.

Page1 / 4

ECE438-F11-midterm - ECE/CS 438 Midterm Exam Wednesday,...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online