In a statement, AAPT, said it was part of a long-term strategic alliance between the two companies, which sees them working together on several partnership opportunities.
Nextep is a wholesale carriage service provider offering broadband services to urban, metropolitan and regional areas.
The acquisition is subject to several standard sales conditions and is expected to be completed by November 30.
"The potential of this partnership with NEC is an exciting addition to our very successful Alliance program, aiming to give customers best-of-breed, pre-integrated solutions of technology, managed ICT and networks from the respective experts in each field," AAPT CEO, David Yuile, said. "AAPT is delighted to welcome all the Nextep customers and is confident, given our extensive broadband experience, they will continue to be well served."