| Protocal | TCP Ports | UDP Ports | Comment |
| DNS | 53 | 53 | |
| Kerberos | 88, 464 | 88, 464 | |
| LDAP | 389 | 389 | |
| LDAPS | 636 | N/A | if used |
| RPC | 135 | 135 | |
| NTP | N/A | 123 | Time sync should be enabled and time accurate |
| Global Catalog | 3268, 3269 | N/A | If used by AD |
| SMB | 445, 139 | N/A | |
| Netbios | N/A | 137, 138 | |
| RPC | 49152-65535 | N/A | Some Active Directory services can use high ports RPC |