In our environment, we have several sites. The number of systems at a site may be small, but they are spread out amongst several subnets within each site. As is proper IP routing design, each site's IP range summarize to one or a very few IP supernets. Since we are using the 10.0.0.0/8 RFC1918 space, we can be very generous with our IP allocations per site. A site with only a couple hundred machines still gets a /16, and follows the same network design as our main site with 10000+ machines. This means that I could have dozens or more /24 networks in the site.
I want to be able to input a summarized supernet into the Explicit Group Update Providers, so that all machines in, for example, 10.250.0.0/16, all point to the local site GUP. Since there is no "subnet mask" field to input, I don't know how SEPM is deriving the mask from the IP. Is it using the old classful system, and thus by default if my IP is 10.x.x.x it's going to assume a /8? Does it assume /24s? Or is it somehow smart enough to assume the end 0.0 implies that the last two octets are hosts? I really just don't want to have to enter in 254 different /24 addresses (10.250.0.0, 10.250.1.0, 10.250.2.0, etc). I also want to make sure that, with our 10.0.0.0/8 network space usage, that SEPM doesn't think that it's a flat network and every host can use any GUP in that full range.