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F<strong>in</strong>d<strong>in</strong>gs and Issues<br />

Figure 3. Barga<strong>in</strong>Bot parallel, multiagent architecture<br />

Purchas<strong>in</strong>g books with the aid of Barga<strong>in</strong>bot has time and money sav<strong>in</strong>g advantages. Perform<strong>in</strong>g similar tasks<br />

would entail track<strong>in</strong>g down and search<strong>in</strong>g multiple bookstores on the Internet, a time consum<strong>in</strong>g process.<br />

Eichmann [Eichmann 1994] exam<strong>in</strong>es the ethics of Web-based agents. Barga<strong>in</strong>bot does not suffer the<br />

<strong>in</strong>efficiencies of recursive retrieval associated with conventional robots. Barga<strong>in</strong>bot knows exactly where to<br />

locate its <strong>in</strong><strong>format</strong>ion and does not produce recursive hits on a server or excessive stress on the network.<br />

The development and use of Barga<strong>in</strong>bot has highlighted numerous issues that need to be addressed if<br />

automated brows<strong>in</strong>g, and specifically automated query<strong>in</strong>g of site databases, is to rema<strong>in</strong> a useful complement<br />

to manual brows<strong>in</strong>g on the network.<br />

Many onl<strong>in</strong>e stores provide little support for effective <strong>in</strong><strong>format</strong>ion query<strong>in</strong>g of their databases. For example,<br />

many bookstores that Barga<strong>in</strong>bot searches, have a Web forms front-end to their database that limits query<strong>in</strong>g to<br />

either title or author, but not both simultaneously. This requires Barga<strong>in</strong>bot to perform an extra level of<br />

filter<strong>in</strong>g to remove unwanted authors from a returned list of book titles. Further filter<strong>in</strong>g is required to remove<br />

redundant markup (HTML) from returned responses. The <strong>format</strong> of data returned from bookstore sites also<br />

varies. Barga<strong>in</strong>bot must apply different filter<strong>in</strong>g mechanisms to different sites <strong>in</strong> order to return comb<strong>in</strong>ed<br />

results <strong>in</strong> a homogeneous manner. Furthermore, changes to the <strong>format</strong> of bookstore responses requires<br />

programmer <strong>in</strong>tervention. The use of mach<strong>in</strong>e learn<strong>in</strong>g techniques to sense and adapt to such changes will be<br />

crucial to the success of similar agents <strong>in</strong> future filter<strong>in</strong>g tasks.<br />

Other problems associated with automated brows<strong>in</strong>g of the Web <strong>in</strong>clude the presence of client-side state<br />

mechanisms to store state <strong>in</strong><strong>format</strong>ion on the client side. State <strong>in</strong><strong>format</strong>ion, whilst useful for manual brows<strong>in</strong>g<br />

of <strong>in</strong>terconnected pages, is often mean<strong>in</strong>gless <strong>in</strong> the context of automated brows<strong>in</strong>g, result<strong>in</strong>g <strong>in</strong> agents hav<strong>in</strong>g<br />

<strong>in</strong>terface problems with site databases that expect such <strong>in</strong><strong>format</strong>ion. Certa<strong>in</strong> sites also make use of session<br />

keys, which time-out after short time <strong>in</strong>tervals, requir<strong>in</strong>g their cont<strong>in</strong>ual renewal.<br />

The above problems could be overcome by the <strong>in</strong>troduction of a suitable merchandise request protocol. Other<br />

possible query<strong>in</strong>g mechanisms <strong>in</strong>clude Z39.50 [Kunze] or an <strong>in</strong>ter-operable agent model [Genesereth et al.<br />

1994]. Technical cooperation amongst site adm<strong>in</strong>istrators and agent ma<strong>in</strong>ta<strong>in</strong>ers is also needed for the effective<br />

use of agent technology <strong>in</strong> electronic commerce. For example, certa<strong>in</strong> sites blocked the Barga<strong>in</strong>F<strong>in</strong>der agent<br />

[URL 2] from search<strong>in</strong>g their databases.<br />

The use of Java [Gosl<strong>in</strong>g & McGilton] as an agent implementation language is be<strong>in</strong>g looked at by many<br />

researchers [URL 3] [URL 4]. Client side execution of agents have numerous advantages. For example, clientside<br />

execution of network operations overcomes traffic rout<strong>in</strong>g that server based filter<strong>in</strong>g mechanisms produce,<br />

hence plac<strong>in</strong>g less stress on the network. Figure 4 illustrates Barga<strong>in</strong>bot <strong>in</strong>terrogat<strong>in</strong>g remote bookstore<br />

databases, filter<strong>in</strong>g its f<strong>in</strong>d<strong>in</strong>gs, and return<strong>in</strong>g the <strong>in</strong><strong>format</strong>ion to the user's browser. Figure 5 shows the<br />

network operations of a client side agent, such as one written as a Java applet. Note there is only one set of<br />

network operations required.

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