Accounting login fail

[debik]

I have in NAS log something like this:
  Dec/08/2005 00:44:33 Accounting login fail 
Dec/08/2005 00:44:28 Send Accounting login message debik
Dec/08/2005 00:44:23 Send Accounting login message debik
Dec/08/2005 00:44:18 Send Accounting login message debik
Dec/08/2005 00:44:18 Authentication success 00-0F-CB-B0-06-86
Dec/08/2005 00:44:18 EAP-Success 00-0F-CB-B0-06-86
Dec/08/2005 00:44:12 Accounting logout fail 
Dec/08/2005 00:44:09 EAP-Response/Identity debik
Dec/08/2005 00:44:09 EAP-Request/Identity 
Dec/08/2005 00:44:08 Wireless PC connected 00-0F-CB-B0-06-86 

What does it mean ??