ktop Virtualization Managing Virtualization Managing Memory, CPUs, and Storage in Virtualized Data Centers LAN Traffic 68 Backbone and Individual Local Area Network Structures 69 Layer 2 Switches 69 Layer 3 Switches (Switching Routers) LAN Backbones in Heavy Traffic Areas Using Virtual Local Area Networks for Specialized Treatment Access to the Internet via Routers 71 IP Private Branch Exchange Systems for Internal Use IP for New Systems 73 The Technology behind IP Telephony 75 Voice QoS and Security 75 Assessing Network Quality by Using Voice Quality Measurements Prioritizing Voice and Video on a Virtual Local Area Network IP Private Branch Exchange Architecture Communications Servers and Voice as an Application on the LAN 78 Media Gateways, Protocol Translation, and Signaling 79 Connecting IP Telephones to Layer 2 Switches 80 Connecting to Branch Offices in a Centralized Services Environment 81 IP Telephony for Small Organizations and Branch Offices: A System in a Box Contents Softphones and Portability 82 Mobility and Single-Number Service 83 Session Initiation Protocol-Compatible Trunks 84 The Demarcation Point at Which Telephone Companies Wire Trunks 84 Circuit-Switched Proprietary PBXs Value-Added Applications for Telephone Systems 87 Integrating Conferencing, Voicemail, Instant Messaging, and E-Mail through UC 87 Remote and Desktop Audio and Video Conferencing 89 Group Video Conferencing in Private and Public Conference Rooms Telepresence: Video Conferencing in High Definition 92 Using Hosted-IP PBX Services 92 Managing Customer Relationships by Using Contact Centers 93 Using Voice Response Units for Routing and Information via Touch-Tone or Speech 98 Summary 100 Appendix 100 Part II Industry Overview 3 Competition, Industry Structures, and Regulations Introduction 108 The 1984 Breakup of AT&T 110 The Creation of Verizon Communications and the Post-2005 AT&T Regulatory Issues Universal Service and Guaranteed Rate of Return 118 ICC Payments for Connecting Traffic 119 The Universal Service Fund 120 Transitio