Table Of Contents - ASCOM i62 Troubleshooting Manual

Troubleshooting Guide
Ascom i62 VoWiFi Handset
Contents
1. Introduction ................................................................................................................... 3
1.1 Target Group ........................................................................................................... 3
1.2 Prerequisite ............................................................................................................. 3
1.3 Material Needed ...................................................................................................... 3
1.4 Software Version ..................................................................................................... 4
1.5 Abbreviations and Glossary .................................................................................... 4
1.6 Information Required by TAC .................................................................................. 5
2. WLAN Overview ............................................................................................................. 6
2.1 The Problem of Legacy WLANs ............................................................................... 6
2.2 WLAN Planning and Provisioning............................................................................ 7
2.3 The Importance of Pre- and Post-Site Surveys ....................................................... 8
2.4 WLAN Dynamics ...................................................................................................... 8
2.5 Troubleshooting Implications and WLAN Design.................................................... 8
3. The VoWiFi Handset as a Wireless Client .................................................................. 10
3.1 VoWiFi Handset Protocol Layers ........................................................................... 10
3.1.1 Troubleshooting the Layers.......................................................................... 12
3.2 Voice Transmission over a VoWiFi System............................................................ 12
3.3 Handset Startup Procedure................................................................................... 12
3.4 AP Scanning........................................................................................................... 13
3.4.1 Active Scanning ............................................................................................ 13
3.4.2 Passive Scanning .......................................................................................... 13
3.4.3 Configured Channels and Scanning Intervals ............................................... 13
3.5 Power Management .............................................................................................. 14
3.5.1 Overview ....................................................................................................... 14
3.5.2 U-APSD PS Mode Operation.......................................................................... 15
3.5.3 Recommended Values .................................................................................. 17
3.5.4 Screen Saver ................................................................................................. 17
3.6 Roaming ................................................................................................................ 17
3.6.1 Idle Mode ...................................................................................................... 18
3.6.2 Call Mode....................................................................................................... 18
3.6.3 System-Aided Roaming................................................................................ 19
3.7 DFS Channel Probing ............................................................................................. 19
3.8 SIP.......................................................................................................................... 20
3.8.1 SIP Components ............................................................................................ 21
3.8.2 SIP Call Setup ................................................................................................ 23
3.8.3 Redirect Servers ............................................................................................ 26
3.8.4 Call Completion ............................................................................................. 26
3.8.5 Message Content .......................................................................................... 27
28 June 2012 / Ver. A
TD 92685EN