1. Peer-to-Peer Information Systems Assignment #6
Old Dominion University
Department of Computer Science
CS 495/595 Fall 2004
Michael L. Nelson
11/30/04

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
do not answer requests from bad friends
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