NEC 28i System Manual page 12

Do Not Disturb
Setting Up Do Not Disturb (cont'd)
For your reference . . .
0406, COS Options - Item 109: Hotel DND Set (Other Phone)
Use this option to enable (1) or disable (0) an extension's ability
to set Hotel DND for another extension. Normally, only the
supervisor's station would have this option enabled.
0406, COS Options - Item 118: Hotel DND Set (Own Phone)
Use this option to enable (1) or disable (0) an extension's ability
to set Hotel DND for itself. If your guests should be able to turn
DND on and off, be sure to enable this option.
1005 - Class of Service
Assign Class of Service to extensions.
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