Cisco SPA525G Administration Guide - Page 117

6 Configuring Security, Quality, and Network Features This chapter describes how to configure security, quality, and network features for the phone. It contains the following sections: • "Setting Security Features" section on page 115 • "Ensuring Voice Quality" section on page 118 • "Configuring Voice Codecs" section on page 123 • "Configuring Domain and Internet Settings" section on page 126 • "Setting Optional Network Parameters" section on page 129 • "Configuring VLAN Settings" section on page 131 Setting Security Features The following features help ensure that calls are secure and authenticated. • "SIP Initial INVITE and MWI Challenge" section on page 115 • "SIP Over TLS" section on page 116 • "SRTP and Securing Calls" section on page 117 SIP Initial INVITE and MWI Challenge SIP INVITE (initial) and MWI message in a session can be challenged by the endpoint. The purpose of this challenge is to restrict the SIP servers that are permitted to interact with the devices on the service provider network, which significantly increases the security of the VoIP network by preventing malicious attacks against the device. Cisco SPA and Wireless IP Phone Administration Guide 115