Unified 500 Series : Overview – IOS Featu re set based on Advanced IP Services 12.4(11)XW4 is the Recommended IOS release for deployments. The software bu ndle UC520-4.2.4.zip can be downloaded from http: //www.cisco.com/cgi-bin/tablebu ild.pl/UC520 U nified 500 Series u ses an IOS featu re set is derived from the Advanced IP Services featu re set The featu re set su pports all of the voice, video, data, secu rity, and wireless featu res with the following exceptions: For Voice – MGCP / CCM / SRST – cannot su pport Cisco Unified Communications Manager For Data – WAN Protocol s su ch as FR / ATM / X. 25 / MPLS / Tag / LAPB For Secu rity – L2TP, IDS/I PS, URL Filtering (Websense, N2H2), Advanced appl ication inspection and control . For Rou ting – Rou ting Protocol s su ch as RI P/OSPF/BGP/EIGRP For Network Management – SNMP Proxy Other – GLBP (l oad bal ancing) CME 4. 2 exceptions – Secu re RTP and Unified Contact Center express integration