Port 67 supports DHCP server and bootps (TCP reference coverage) across distinct transports. Review each protocol before writing firewall or monitoring policy.
Server-side DHCP address and network-configuration service.
DHCP clients broadcast requests to a server or relay on UDP 67.
Client to server
Control rogue DHCP servers, secure relay paths and use switch protections such as DHCP snooping where appropriate.
bootps (TCP reference coverage) is documented as a network service convention for port 67 over TCP.
Use this reference entry when identifying or validating systems documented to use 67/TCP.
Varies
Confirm the listening process and current vendor documentation before permitting traffic; a listed convention does not prove the active service or its security posture.