If you are connecting to an ADSL2+ service then you need an active landline for the data to be delivered to your home.
It is important to remember that having an active phone line doesn't mean you need to have a home phone service. Many service providers bundle phone line rental into the cost of broadband plans, but do not include home phone calls with these plans.
Alternatively, you might consider a Naked DSL plan, which is similar to ADSL2+ but doesn't require an active phone line.
If you are connecting to the NBN or Cable Broadband you do not need an active phone line.