Cisco 7906G Administration Guide - Page 25

Chapter 1 An Overview of the Cisco Unified IP Phone What Networking Protocols Are Used? Table 1-1 Supported Networking Protocols on the Cisco Unified IP Phone (continued) Networking Protocol Link Layer Discovery Protocol-Media Endpoint Devices (LLDP-MED) Real-Time Transport Protocol (RTP) Real-Time Control Protocol (RTCP Secure Real-Time Transport Protocol (SRTP) Purpose Usage Notes LLDP-MED is an extension of the The Cisco Unified IP Phone supports LLDP standard developed for voice LLDP-MED on the SW port to products. communicate information such as: • Voice VLAN configuration • Device discovery • Power management • Inventory management For more information about LLDP-MED support, see the LLDP-MED and Cisco Discovery Protocol white paper: http://www.cisco.com/en/US/tech/tk 652/tk701/technologies_white_pape r0900aecd804cd46d.shtml RTP is a standard protocol for transporting real-time data, such as interactive voice and video, over data networks. Cisco Unified IP Phones use the RTP protocol to send and receive real-time voice traffic from other phones and gateways. RTCP works with RTP to provide QoS data (such as jitter, latency, and round trip delay) on RTP streams. RTCP is disabled by default, but you can enable it on a per phone basis by using Cisco Unified Communications Manager. For more information, see the "Network Configuration" section on page 4-33. SRTP is available in addition to RTP. SRTP adds security by encrypting media streams during data transport. For SRTP to work, the phone or phones being called must also support SRTP or else those phones cannot decrypt the secure media stream. OL-14585-01 Cisco Unified IP Phone 7906G and 7911G for Cisco Unified Communications Manager 6.1 1-7