MDUGs differ from regular PRGs in the following ways:
All members, including the prime member, must have a Service Level of Multi-Device This Service Level indicates that the directory number (DN) is assigned to a user that has only basic telephony functionality (e.g., emergency or attendant calls) until programmed as a member of a Multi-Device user group or suite. The DN does not use an IP User License. However, the group or suite has a Multi-device Users or Multi-device Suites license which one person can use at a time in order to receive full telephony service..
When one member of the group is engaged in a call:
callers will receive a busy signal (in other words, "One Busy All Busy" is always enabled).
the other members of the group will be restricted to IP Device Only This Service Level indicates that the directory number (DN) is assigned to an unlicensed device that has only basic telephony functionality (emergency or attendant calls). The device becomes functional when a hot desk user or hot desk ACD agent logs into it. behavior (similar to Phone Locked activation for a regular set).
When the group is deleted or the prime member ceases to be a member of the group, the prime member becomes a Full Service This Service Level indicates that the directory number (DN) is assigned to a standard user and device with full telephony functionality. user and consumes either an IP User License or an External Hot Desk Users license (if available).
Note: That same prime member cannot be made a Multi-device User Group prime member again until its DN is deleted, and then re-added. The reason why is that Full Service is a less restricted service level than Multi-Device and going from a less to a more restricted level is not allowed. See Assigning a Service Level to Records for more information on changing the Service Level of a DN.
It is not possible to delete the group while any one of its members is logged in as a hot desk user or external hot desk user (EHDU).
Busy Lamp Field (BLF) is supported for either prime or non-prime DNs of MDUG member phones, depending on the state of the System Option, 'BLF - Busy Indication Based on Set Enabled'.
If the option is set to NO, the BLF indicates 'busy' when any member of the MDUG is active on the prime line of their telephone.
If the option is set to YES, the BLF indicates 'busy' when any member of the MDUG is active on any line of their telephone.
Note: The above behaviors also apply to multicall appearances of the MDUG prime member.
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