<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><br></div><div><div>The best data you can get is from the RISPort API as mentioned by Abel, however you need to parse the data for each phone as you get the last registered date for each subscriber in the cluster the phone has registered with while the cluster has been online. So if a phone bounces between two nodes you need to find the latest date to understand when the last registration event occurred.</div></div><div><br></div><div>I've attached a sample export from PhoneView, this is an application that uses the RISPort API and happens to capture the last Registration Date for all phones in the export (File->Export)</div><div><br></div><div>If you have a look at some dates from your own environment you can download PhoneView from <a href="http://www.unifiedfx.com">http://www.unifiedfx.com</a>.</div><div><br></div><div>Note: You need to select the format of the Timestamp column to see the date or time the registration happened</div><div><br></div><div>Thanks</div><div><br></div><div>Stephen</div><div><br></div></body></html>