Sorry for the newb question, but how does public peering fit in with bandwidth providers?
Public peering is simply peering through a public exchange, which generally involves a layer 2 switch fabric. You only have one physical connection to and port on the exchange, but you can connect to any other participant at that exchange. You would need an ASN and your own IP's advertises as /24's or larger to do this though.
From what little you've stated though, my guess would be that it's your provider that participates at a public peering exchange, which helps reduce their bandwidth costs, and they are somehow passing on the savings to you.
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