We are planning our BGP implementation and creating our subnets from our provided /22 IP block. We are aware of the fact that most ISP's will not advertise any subnets smaller than /24. But we would like to split our /22 IP block between our various sites without using more IP addresses than we have to. Our plan was to split the /22 block into /25 blocks and then split a couple of the /25 blocks into smaller blocks. But even if our ISP's agree to advertise the smaller blocks, they will most likely not get advertised throughout the Internet. Is there some way to split the /22 block into blocks smaller than /24 and still get them advertised throughout the Internet? We have five sites and we do not want to use /24 blocks at each site and waste unused IP addresses.