Hello All,

I need feedback from the forum as to what should be the correct answer to this practice question found in the book:
"IP Telephony Self-Study Cisco QoS Exam Certification Guide, Second Edition by Wendell Odom/ Michael J Cavanaugh"

The question is:

what fragment size, in bytes, should be used on a 256-Kbps link in order to ensure each fragment has less than or equal to 10 ms of serialization delay?

a. 80
b. 160
c. 214
d. 240
e. 320
f. 480

The book is stating that the correct answer is D. but when I use the formula:

fragment-size * 8/linkspeed = serialization delay

I come up with the answer of E. (320).

Can you someone help me understand which answer is correct and why?

Thanks in advance for your help.

Adil Nasser
adil.nasser@gmail.com