David,
Am I the only one who knows what "Wikipedia" or search engines like "Google", "Ask", "Live Search", and "Clusty" are used for? You know, quickly looking up information on the internet. But then I guess it is just easier to ask people to spoon feed you.
http://en.wikipedia.org/wiki/Load_ba...28computing%29
http://en.wikipedia.org/wiki/Failover
http://en.wikipedia.org/wiki/Link_aggregation
http://en.wikipedia.org/wiki/Split_multi-link_trunking
Everything most people ever wanted to know about the network options available on the Guardian OS. Took me about 3 minutes to find those links on Wikipedia. Forget the last two if you do not want to buy a managed switch and have Guardian OS v5.x
Bottom line is, unless you have enterprise type equipment (like a managed switch) and that type of knowledge level, you probably should not be using these other networking modes.