Refer to System Provisioning - Zone.
Sub-system signaling ports (such as SIP signaling ports, relay ports, D-SBC signaling ports, H.323 signaling ports) must use different IP addresses because each IP address adds one system ACL, and IP addresses are not prioritized when measured in the same ACL. This best practice will avoid any IP addressing overlaps and ensure proper policing of packets.
Additional topics in this section: