Telstra is implementing a three-digit number for VoIP calls to emergency service operators to ensure critical information such as exact location and address can be recorded.

VoIP has played havoc with emergency services globally because, after the call goes through the gateway, no hard location information is forwarded with the call. This means emergency services personnel are unable to automatically track the caller to their destination.

At present, emergency services despatchers within Telstra can locate VoIP callers only by asking for their address; however, the new number system aims to reduce any further problems - even going as far as developing a position paper for the Department of Communications, Information Technology and the Arts (DCITA) about the issue.

Jane Elkington, emergency services answer point manager for Telstra, said the telco has asked all VoIP carriers and providers to attach a VoIP code (number 98) so despatchers automatically know the call is coming from a VoIP phone so they can ask additional questions.

"We are trying to flag VoIP services so despatchers can verify the details rather than assuming the caller is correct; there is difficulty doing this with existing VoIP services. Therefore, we have asked all carriers and providers of VoIP to attach a VoIP code on calls, such as a 98," Elkington said.

"In the interim we have put a position paper to DCITA on the suggestions of using a separate number range for VoIP so our operators and the emergency services know the call is coming from a VoIP service.

"We do around 35,000 calls a day and all it takes is one to go astray, of which there have been a few examples with VoIP."

Paul Harris, telecommunications project development manager at the bureau of emergency services for the Department of Justice in Victoria, said VoIP has presented a certain number of challenges for emergency services. He said nobody is told when they take up a VoIP service that they cannot actually dial triple-0 effectively.

The danger arises, he said, when someone who has bought VoIP as a secondary service then considers it good enough to be the primary service and disconnects the fixed line. "They don't realize they do not have the ability to call triple-0," Harris said

"The other issue is the caller line identifier; even when you call the triple-0 service the PSDN (Public Switch Data Network) accesses the integrated public database which gives the emergency services phone operator a certain amount of information which includes caller and identifiers such as location, but imagine what happens when you throw in IP?"

"VoIP services causes havoc in being able to spin off some sort of locational information."