CIS 331: Network Introduction
Lehman College, City University of New York
Spring 2015
This Homework Is Due By 11:59 PM on Sunday March 1, 2015
Explain fragmentation as it relates to datagrams. Why is it necessary? Where does
it occur? When and where are the fragments reassembled? Give examples and be as
specific as possible.
What is the function of the Time To Live (TTL) field in a datagram header?
Explain how ICMP messages are encapsulated.
Should ICMP messages contain a timestamp that specifies when they are sent? Why of why not?
Should a router give ICMP messages priority over normal traffic? Why or why not?
Come up with the routing tables for all the routers: A, B, C, D, E, F, and G.
Host 70.0.0.9 must receive his packets only from router E. All other traffic
to network 70.0.0.0 may arrive from other routers. Router H is the router
used to access the Internet.
Please submit the completed assignment on Blackboard as a typed Microsoft Word file or a PDF file.
No other forms of submission will be accepted.
