3CX Academy Intermediate Certification Practice Test

Enabling the setting to "Disallow use of extension outside the LAN" does not block remote 3CX clients from registering. Instead, this option is designed to restrict the use of extensions to the local area network (LAN) only. When this setting is enabled, any SIP clients or endpoints attempting to register from outside the LAN will be denied access due to the configuration, but remote clients can still register if they are set up to connect successfully, provided they are not affected by other network configurations or security features. This setting primarily is a security measure that ensures only local devices can use the specific extensions, while remote devices can still be configured to connect through secure channels or with appropriate permissions, contingent on the 3CX server's firewall settings and NAT configurations. Thus, while it limits the use of extensions to the LAN, it doesn’t strictly block remote clients from being able to connect if other configurations allow it.