Lorim,
You need to establish the 'presentation' of the service from Magnet - in other words, what does Magnet present as a physical medium for the service ? It is very unlikely (but possible) that the presentation is fibre in a domestic situation. It will be fibre coming off the road and then this will terminate in a box/device of some sort - it is the connection coming out of this box that you are interested in. If it is ethernet/RJ45 then you have a standard presentation that most of the routers you will see in the computer shops will work on. Asking Magnet should provide the answer, but equally if you look at it (and know what to look for) you could determine this yourself.
z