Getting Started with Your SoundPoint IP 550 Phone
15.Line Indicators—Individual multi-color LEDs display the dynamic call state and remote user status (busy lamp field (BLF) and presence). The mapping is:
—Solid green—An active call is in progress.
—Fast flashing green—There is an Incoming (ringing) call.
—Flashing red—The call is on hold.
—Solid red—The line is busy remotely (shared lines).
16. Line Keys 
—Use these keys to activate up to four lines or speed dials that can be assigned to your phone. The associated icons represent:
—Registered line 
—Registered shared line 
—Unregistered line 
—VoiceMail/Messages 
—Speed-Dial 
—Ringing 
—Call if progress with HD Voice
—Call Forward 
—Do Not Disturb 
—Conference 
—Presence/BLF 
