The NSW government is believed to be looking at strategies to speed up the train trip between Wollongong and Sydney.
Earlier this year, the NSW government granted AECOM Australis a contract worth $924,760 to conduct a study "to prepare rail corridor strategies" along the Sydney-Wollongong corridor.
The contract also called on AECOM to look at the Sydney-Newcastle and Sydney-Canberra corridors.
A spokesman for AECOM, an international company that provides a range of infrastructure support services, directed any inquiries on the research to the NSW government.
Transport for NSW would not comment on whether the study was designed to identify ways to speed up trains.
"As outlined in the NSW Long Term Transport Master Plan, the NSW government is investigating improvements to timetabling, travel speeds and service frequency along key regional rail corridors," a spokesman said.
"Work to develop strategies for regional rail corridors between Sydney-Wollongong, Sydney-Newcastle and Sydney-Canberra, is now under way."
However, faster trains along the Wollongong to Sydney rail corridor have been identified as a priority in Infrastructure NSW's recommendation for government spending.
INSW said the government needed to try to reduce the Wollongong to Sydney travel time to one hour.
The master plan also lists a reduced transport time between Wollongong and Sydney as a goal.
The revised rail timetable introduced in October last year was also created with the aim of getting at least some peak-hour trains running faster. Under the current timetable, the fastest Wollongong to Sydney times are about 90 minutes.
University of Wollongong rail expert Philip Laird said it was possible to bring it down to an hour.
"You could get the timetable a bit sharper by getting it to where it was in 2005 and that might give you a 10-minute saving," Mr Laird said.
"But beyond that, you need some infrastructure investment. No single solution will get you down to an hour; it will be a combination of things."
These included more powerful trains, removing the "deviation" at Helensburgh and construction of the Maldon-Dombarton line.