Foundation Question for Cabin

[Trailnut]

I'm building a 30'x40' (40'x40' if you count the 10' front porch) cabin and would like y'all's thoughts on is a 2'x2' footing around the perimeter of the foundation enough?  Or do I need a footing/beam in the center of the foundation also.
This is sandy loam soil in Arkansas.

Thank y'all for any help   

[ChugiakTinkerer]

A little more detail would probably be helpful.  The answers will depend greatly upon the design of the house as well as the strength of the soil.  The IRC is available online and gives specific footing requirements (2009 version here).

Depending on how you plan to support the floor, you may need one or more beams supporting the center.  The area of the footing below those support piers also depends on the load above being supported.  Footing thickness for concrete reinforced with rebar is typically 8".