Maybe switch in your network support DHCP snooping. DHCP snooping block package, if don't use DHCP.
In computer networking DHCP snooping is a series of techniques applied to ensure the security of an existing DHCP infrastructure.
When DHCP servers are allocating IP addresses to the clients on the LAN, DHCP snooping can be configured on LAN switches to harden the security on the LAN to allow only clients with specific IP/MAC addresses to have access to the network.
DHCP snooping is a series of layer 2 techniques. It works with information from a DHCP server to:
- Track the physical location of hosts.
- Ensure that hosts only use the IP addresses assigned to them.
- Ensure that only authorized DHCP servers are accessible.
In short, DHCP snooping ensures IP integrity on a Layer 2 switched domain.