5.9 Configuration of Users .................................................................................................2405.10 Programming E-mail Integration for UM Voice ..........................................................2425.11 Automatic Configuration of Mailboxes .......................................................................2466 Methods of Stacking Expansion Units ...............................................2496.1 Methods of Stacking Expansion Units ........................................................................2507 Troubleshooting ...................................................................................2537.1 Troubleshooting ............................................................................................................2547.1.1 Installation ....................................................................................................................2547.1.2 Connection ...................................................................................................................2577.1.3 Operation ......................................................................................................................2587.1.4 Error Messages ............................................................................................................2597.1.5 Restarting the KX-NS500 .............................................................................................2617.1.6 Troubleshooting by Error Log .......................................................................................2638 Networking Information .......................................................................2658.1 Information about Using an IP Network ......................................................................2668.1.1 Using a VoIP Network with the PBX .............................................................................2668.1.2 DHCP (Dynamic Host Configuration Protocol) Server .................................................2698.1.3 VLAN (Virtual LAN) ......................................................................................................2708.1.4 Jitter Buffer ...................................................................................................................2718.1.5 Voice Activity Detection (VAD) .....................................................................................2718.1.6 Network Configuration ..................................................................................................2728.1.7 Network Devices ..........................................................................................................2768.1.8 QoS (Quality of Service) ...............................................................................................2778.1.9 Network Time Protocol (NTP) ......................................................................................2788.2 H.323 Trunks ..................................................................................................................2798.2.1 Avoid Multiple IP Networks ...........................................................................................2798.2.2 Gatekeeper ...................................................................................................................2808.2.3 Bandwidth Assessment ................................................................................................2808.2.4 Virtual VoIP Gateway Card Specifications ...................................................................2838.3 SIP Trunks .....................................................................................................................2848.3.1 IP Telephony Service ...................................................................................................2848.3.2 SIP Requirements ........................................................................................................2878.3.3 Router Requirements ...................................................................................................2878.3.4 Bandwidth Requirements .............................................................................................2878.3.5 Virtual SIP Trunk Card Specifications ..........................................................................2898.4 Types of PBX Networks ................................................................................................2908.4.1 H.323 QSIG Network ....................................................................................................2908.5 Port Security ..................................................................................................................2919 Appendix ...............................................................................................2959.1 PBX Region Suffix Codes and Areas ..........................................................................2969.2 System Prompt Languages ..........................................................................................29712 Installation ManualTable of Contents