What issues will we face with the use of network surveillance tool in the company network with respect to the Telecommunication Interception Act and Privacy Act ?
And what policies could be implemented to mitigate these issues ?
If you are thinking of monitoring the network traffic of your own employees:
The most important thing you can do is warn your users that their communications are subject to monitoring by the company at any time, and they should have no expectation of privacy in their communications.
If you are thinking of building surveillance capabilities into your networks:
One security risk is that the surveillance capability provides a way for attackers to eavesdrop on traffic without authorization. I know that surveillance capability is only intended for use by law enforcement, but building it into your systems introduces the risk that it could be misused.
For an eye-opening example of this risk, I encourage you to read up on the Greek wiretapping case in 2004-2005, around the time of the Olympic Games in Athens. In 2005 it was discovered that the Greek telecommunication carrier's surveillance systems had been compromised and were under the control of unknown external agencies, who used the surveillance capability to wiretap over 100 cell phones belonging to key government officials: the prime minister, minister of defense, minister of foreign affairs, members of parliament, and so on. The wiretapping capability had been build only for use by Greek law enforcement, but someone else took control. They wiretapped phones for 10 months before the compromise was detected; no one ever figured out who did it, but given the sophistication of the attack, it's natural to suspect foreign spy agencies.
For more on the risks of building surveillance into networks, I recommend the following articles:
Check with your legal department, but all that should be required is that you provide ample notification to users who may be monitored. These should be in the form of notices within an Acceptable Use Policy which is signed by employees and contractors prior to granting network access, as well as Warning Banners implemented in one form or another on all networked equipment and applications.
Whatever the form, your notification should cover the following points:
(I am not a lawyer, and this is not legal advice.)