Troubleshooting239jitter, due to message recombination of transmission or receiving equipment (e.g.,timeout handling, retransmission mechanism, buffer under run). Noisy equipment, such as a computer or a fan, may cause voice interference. Turnoff any noisy equipment. Line issues can also cause this problem; disconnect the old line and redial the callto ensure another line may provide better connection.What is the difference between a remote phone book and a localphone book?A remote phone book is placed on a server, while a local phone book is placed on theIP phone flash. A remote phone book can be used by everyone that can access theserver, while a local phone book can only be used by a specific phone. A remotephone book is always used as a central phone book for a company; each employeecan load it to obtain the real-time data from the same server.What is the difference among user name, register name anddisplay name?Both user name and register name are defined by the server. User name identifies theaccount, while register name matched with a password is for authentication purposes.Display name is the caller ID that will be displayed on the callee’s phone LCD screen.Server configurations may override the local ones.How to reboot the IP phone remotely?IP phones support remote reboot by a SIP NOTIFY message with “Event: check-sync”header. When receiving a NOTIFY message with the parameter “reboot=true”, the IPphone reboots immediately. The NOTIFY message is formed as shown:NOTIFY sip:@ SIP/2.0To: sip:@From: sip:sipsak@CSeq: 10 NOTIFYCall-ID: 1234@Event: check-sync;reboot=true
