When asked by Justice Murray Wilcox on what he thinks should be the solution to the P2P "dilemma", the University of Berkeley professor of computer science and information management said that technology is the answer to keep users from infringing copyright.
Justice Wilcox said the peer to peer "dilemma" was how not to impinge on people sharing non-copyright material and at the same time reduce, if not eliminate, the amount of sharing of infringing material.
"My own belief is that the best way to address these issues is through technology that keeps users from infringing copyright in that way and there's extremely rapid progress being made in this area. For example, Windows now offers WMA format files that have something called Digital Rights Management. The digital rights management system makes it very difficult for users to exchange those files," Tygar said.
"Watermarking technology that's been developed can help assist in catching cases where infringement happens. I believe that the problem is so pervasive of copyright infringement in our society that legal mechanisms alone can never address this. My belief is that as long as there is a substantial non infringing use of a technology, it's not the technology that can be shut down but individuals who pursue additional technologies," Tygar said.
Justice Wilcox admitted he had no idea as to the extent of use of the P2P technology for infringing copyright.
"In this case we don't even know the extent of the non-infringing use. If somebody asked me tonight what is the proportion of infringing material compared to non-infringing I would have to say, I haven't got a clue. The evidence does not reveal that. I don't know whether it's 99.5 percent infringing or 0.45, I have no idea. This is part of the problem, that we know so little about it," Justice Wilcox said.
In his affidavit, Tygar said that it is generally not possible to accurately verify in the Kazaa system that the country the user specifies is actually the country in which the user is using the computer.
Kazaa distributes its Web pages using the Akamai server network. Akamai is a third party that distributes a wide variety of Web content.
According to Tygar, Akamai technology allows the creation of a list of IP addresses accessing a particular Web page or set of Web pages. He said that it is possible for Akamai to create a list of IP addresses of computers accessing Kazaa Web pages.
However, he believes that even if Akamai created such a list of IP addresses, Akamai has no way of knowing what files the Kazaa Media Desktop (KMD) users make available for uploading or what files KMD users download.
"For this reason, Akamai cannot know -- and consequently cannot inform Sharman -- whether its Kazaa Web pages are being accessed by users exchanging public domain files, copyright files with authorisation, copyright files without authorisation, or by users not uploading or downloading any files. Furthermore, a list of IP addresses would not yield information about end users," Tygar said.
Tygar added that Sharman's Web site plays no critical function in the file transfer. "As Sharman does not have access to any nodes or supernodes -- other than those it might operate itself-- the vast majority of file sharing traffic occurs beyond its knowledge or control. Even by examining a supernode, Sharman would only be able to identify that users at particular IP addresses had files with certain metadata. An IP address is not sufficient to identify a user," he said.
Metadata is the annotations added onto files. For instance, files containing sound recordings contain extensive annotations -- especially in the case of musical recordings. These can be annotated with genre information such as folk, rock, classical; the title of the recording; the recording artist; band or orchestra etc.
Tygar said he did not find any evidence that Sharman collects information that would allow it to identify most users and that KMD does not include any features that collect information on Kazaa users or their operations that is sent to Sharman Networks.
He added that if Sharman were to cease to distribute the Kazaa application on its Web site, users could continue to obtain it through several methods.
"First, it is widely available on the Web. Second, it can be exchanged from user to user. From a technical standpoint, Sharman has no control over the distribution of these copies," Tygar said.
"In any case, Sharman is not in a position to stop infringing activity. Even if Sharman were ordered closed immediately, Kazaa users could continue to search for files."
Patent and Trademark attorney Michael Bates also testified for the applicants [record labels] today saying that he noticed there were several changes to the computer's registry after the installation of the Kazaa software.
"Some of the changes to the registry correspond to use of the software and others are made without any user activity, from time to time. These include changes to the supernode IP addresses and access controls that could permit remote access to the user computer. The changes made to the registry when there is no user initiated activity is unable to be controlled or cancelled by the user. The updating of supernode IP addresses occurs without the user's knowledge," he said.
Bates also said that during his examination of the Kazaa software, he observed "abnormally high CPU usage on the test computer".
"I observed abnormal computer function with the computer not responding to my commands. I then checked the CPU processes and observed when I did that the Kazaa software application at that time had taken the majority of the available computer processing capacity at a load of 96 percent."
Justice Wilcox has scheduled a special Saturday morning session to take evidence from visiting US academic Professor Keith Ross, who is testifying for Sharman Networks.
Ross is being cross-examined on allegations that he included material in his sworn affidavit which had been written by solicitors. Draft documents quoted him saying to Sharman parties' solicitors "I was not aware of this, even after our testing. But if you say so, then fine with me".