I do not have visibility into a sites PE as its managed by provider. From what I can see we own out /24 subnet according to ARIN, but I cannot find an associated ASN registered to us. So how is this working from a provider standpoint? Are they advertising our public address space with their ASN tied to the site?
you can check this in a public looking glass that allows you to issue
show ip bgp <prefix>
show bgp <prefix>
The rightmost last AS number before the origin code (either i or ?) is the AS number that is publishing your prefix.
Once, a nice page for finding looking glasses was
Hint: if you are using a private BGP AS number in range 64512 -65535 the ISP overrides it with its own AS number.
Hope to help
As recommendation, if you own a /24 you should get your own AS also and then you should be the one advertising it to your ISP.
You will have more control and flexibility that way.
Rolando A. Valenzuela.
Having your own /24 does not necesseraly qualify you for getting an AS number from the Regional Internet Registry (RIR). The main requirement for obtaining an AS number is to have a routing policy that is different than your service provider. This requirement is not met if you are connected to a single service provider (single homed).