While I like to use electric fencing for quick temporary fences, I do think its important to have a strong permanent fence for the boundary, around the house yard and, on a larger property, other fences to divide the property into paddocks.
This ensures that your cattle stay on your property even if your internal electric fence fails (for example, it the battery runs flat). For cattle, barbed wire is essential, at least four strands, if not five. Animal mesh can also be used, especially if you also keep goats or sheep, but be aware that cattle can climb over mesh by stepping on each section and gradually pulling it down (it sounds ridiculous, but I have seen this happen a couple of times), so a barbed wire top strand is needed to prevent fence climbing.
To read the rest, see my article on Farm Style.
Anything to add?