Revolutionarily new design The Yealink SIP-T42S has been designed by pursuing ease of use in even the tiniest details. The Yealink SIP-T42S boasts a paperless label design, a new foot stand with two positions for the device, non-slip rubber feet, and ergonomic recessed buttons. HD Audio Yealink Optima HD Voice refers to the combination of software and hardware design as well as the implementation of wideband technology to maximizes the acoustic performance. Coupled with advanced acoustic clarity technology such as full duplex, echo cancellation, and adaptive jitter buffer. Enhanced Call Management The SIP-T42S supports vast productivity-enhancing feature such as SCA, BLF List, call forward, call transfer, 3-way conference. Three pages of 6 flexible buttons are shown on the display, and can be programmed up to 15 various features. The T42S supports the Yealink YHS32, and when combined with the Yealink EHS36, a user can control phone calls through their wireless headset. Efficient Installation and Provisioning Dual-port Gigabit Ethernet is designed for flexible deployment options and lower cabling expenses. Integrated IEEE 802.3af Power-over-Ethernet allows easy deployment with centralized powering and backup.The SIP-T42S supports FTP, TFTP, HTTP, and HTTPS protocols for file provisioning and uses Trivial File Transfer Protocol (TFTP) by default. The T42S supports AES encrypted XML configuration files. Highly secure transport and interoperability The T42S uses SIP over Transport Layer Security (TLS/SSL) to provide service providers the latest technology for enhanced network security. The range is certified compatible with 3CX, Asterisk and Broadsoft Broadworks, ensuring compatibility with leading soft switch suppliers.