Many Linux modules, like SSH or Apache or SSL/TLS (HTTPS), are applications that open Ingress network services. Avaya reduces the Ingress network services only to those that are necessary for its telephony applications, thus minimizing exposure of the operating system to network-based attacks. Avaya disables, by default, less secure network services like TELNET and FTP, although customers can enable these services as needed. The customer can enable the FTP Server, Telnet Server, SAT (Telnet 5023) and disable SSH Server, High Priority SSH, and SAT (SSH 5022) using the SMI - Administration > Server(Maintenance) > Security > Server Access page. For more details see Benefits of SSH/SCP over Telnet, FTP and SNMP