Why do some of my sources within the network show only as IP addresses and some as their hostnames. Is there a setting somewhere that I have missed to change them to show hostnames.
No setting, however, the hostnames are derived by the edge by snooping DHCP requests so if a device is statically addressed and/or if its DHCP address doesn't traverse the edge (i.e. if there's a local domain controller, etc.) you'll only see the IP address instead of a hostname.