What you are after is weld mesh at least 1mm or 19 gauge in thickness (the lower the gauge the thicker the wire) anything thinner and a fox can rip into it. The stuff marketed as chicken wire is so thin that it is quite frankly useless.
I built two 3.6m x 2.5m x 1.8m runs last summer and bought wire off these people on eBay, it was decent stuff and delivered quite quickly.
http://www.ebay.co.uk/itm/YELLOW-LABEL-GALVANIZED-WELD-MESH-1200mm-4ft-x-25mm-x-25mm-X-1-0mm-X-25m-/111869992836?hash=item1a0bf89f84:g:FV4AAOSw3ydVrku3