The service is a purpose-built site conforming to Defense Signals Directorate Gateway Certification (certified by the Australian Security and Intelligence Organization) standard T4 and BS 7799, offering high-speed Internet and secured extranet, antivirus, intrusion detection and secure hosting.
The CASA Web site will be hosted at the Macquarie Telecom "Intellicentre".
A CASA spokesperson said the move was prompted by an internal review of its Web systems which found they were not DSD compliant.
"The one area we were falling down was at the gateway in terms of virus protection and the easiest way was to outsource the gateway," the spokesperson said.
"We looked at 90East, then went to market ... at the moment we are paying around A$14,000 (US$10,270) a month but that price is scalable due to traffic."
Macquarie Telecom provides secure services to many government agencies under Gateway Certification, including the Office of the Prime Minister and Cabinet; however the private sector can use the service as well - if such strict security controls are deemed necessary.
The Intellicentre is just two floors housed above Pitt St, Sydney, on the outskirts of the CBD. A demilitarized zone serves private sector clients, with a separate section for government clients. Access to the DSD and governmental section is controlled by a number of steel doors - two with biometric access panels.
The city location is of no extra security concern for CASA, according to Macquarie Telecom's executive managing director of hosting and security, Greg Thomson. The center is on a separate power grid to the CBD and the city location is more beneficial to customers than being "out in the boondocks", he said.
"It is more about the economics of being an outsourced infrastructure provider - if you can do all that it doesn't really matter where you are."
CASA's infrastructure services manager, Gray McLaren, said potential disruption to the CASA Web site was a chief driver to moving to a hosted environment.
"The consequences of any major disruption to Web site availability would be serious for CASA," McLaren said.
"IT could ultimately affect some airline operations both in Australia and overseas, as well as public and government confidence in our organization."
A spokesperson for CASA said the contract is very specific in terms of service level agreements (SLAs) in terms of virus and patching, adding that a planned outage last weekend was proof enough.
"We had our computer room shut down on the weekend for annual cleaning - we moved the Web site to a different server and the e-mails did bank up," the spokesperson said.
"On Saturday, Macquarie noticed this, rang us and said we had a problem; however, we were already on top of it."