The most effective predator barriers I know of are made of chain link fencing.
The material is tough stuff and offers serious protection against common predators.
The advantages of using "cyclone" fencing are many.
The drawbacks are few.
Here is why I use chain link fencing:

• It can't be bitten through like welded wire.
  Even domestic dogs can bite through welded wire fencing.
  
• For the strongest and most determined predator, this type of fencing can be a show-stopper.
  
• The scrap yard or fencing company usually has some to sell at rock bottom prices.
  
• This type of fencing lasts a lifetime.
  
• It comes in heights from 4 feet to 8 feet.
  
• If you lay it down on the ground it will provide a dig-proof barrier.
  

The disadvantages of chain link fencing can be summed up as follows:

• It's heavy and awkward for one person to handle.
  
• Modifying it can require bolt cutters and power tools with metal cutting blades (usually not carried nor operated by predators).
  

If you think "cyclone" fencing can thwart the predators on your homestead, then give the local fencing companies a call.
Many times they'll keep scrap fencing around to sell.
Get the 9 gauge fencing instead of the 11 gauge residential quality.
The heavier fencing is more difficult to work with, but it will stand up to any predator you're likely to encounter.
Make your animal enclosures predator proof.
Use chain link fencing instead of poultry netting for chickens because chicken wire only keeps chickens in - it doesn't keep predators out.