1. Peer-to-Peer Information Systems Week 14: Assignment #6
Old Dominion University
Department of Computer Science
CS 495/595 Fall 2003
Michael L. Nelson
11/25/03

2. Assignment #6
Implement a trust metric as discussed in the previous lecture
Summary:
continue to leave “friends” out of the register verb
add 2 verbs:
listFriends
listBadFriends

3. Friends List <friends> <friend>
<host>cirrus.cs.odu.edu</host>
<port>3923</port>
<client>VTRULZ</client>
<trust average=“0.95” total=“25.65”
frequency=“27” />
<friendsTrust average=“0.90” total=“315”
frequency=“350” contributors=“11” />
</friend>
</friends>

4. BadFriends List <badFriends> … <friend>
<host>riaa.cs.odu.edu</host>
<port>4000</port>
<client>VTRULZ</client>
<trust average=“0.125” total=“0.5”
frequency=“4” />
<friendsTrust average=“0.066” total=“1”
frequency=“15” contributors=“6”/>
</friend>
</badFriends>

5. Notes <friendsTrust> is an aggregate metric -- must be updated
<trust> must be updated too
user interaction:
after each transaction
can use default values
can use any value between 0 - 1
specify preferences for trading partners:
trust level
age (i.e., number of transactions)
grace period for new comers
trust and age

6. Notes someway to show a list of friends and bad friends to the user
someway to show trust level
must be able to specify weights for local and remote trust
must have a button to allow for on-demand polling of all friends
issue listFriends and listBadFriends to all known friends
(good) friends that is, you don’t communicate with bad friends

7. Grading 1/6 of your total project grade You will be graded on:
10 % of your course grade
You will be graded on:
in class presentation
appearance of the interface
nice & creative display of the metadata is encouraged!!!
whether or not it works
practice before you show up for class!
robustness of handling exceptional conditions
these are end-user applications… they should behave like them