Topic Last Modified: 2010-07-18
Microsoft Communications Server 2010 introduces the ability to give users a second, private telephone line in addition to their primary telephone line. Private telephone lines are often assigned to executives and others who want an unlisted telephone number at which they can be reached directly.
Private telephone lines can only be configured with the Communications Server Management Shell. You cannot configure private telephone lines with the Communications Server Control Panel. Private telephone lines should be configured only in deployments of Communications Server 2010 and not in mixed deployments.
Characteristics of Private Telephone Lines
Although the concept of a second, private telephone line is fundamentally simple, it is important to understand the characteristics of private lines and the ways in which they are similar to and different from users’ primary telephone lines.
General Characteristics of Private Telephone Lines
- A user can have only one private telephone line.
- A user with a private telephone line has only one voice mailbox
and receives missed call notifications at a single e-mail
- A user with a private telephone line does not have a second SIP
address, and a second, private telephone line does not give a user
a second presence on the network (such as a second instant
- Private telephone lines are available for on-premises
deployments only. They are not available with hosted deployments of
Microsoft Communications Server.
How Private Telephone Lines Differ from Primary Telephone Lines
- The telephone numbers for private telephone lines do not appear
in the telephone directories or contact lists that are derived from
- None of the following features are available with a private
telephone line: call forwarding, boss/admin, team call, delegation,
team ring, and Response Group Service.
- Calls to a private telephone line have a special ring, and the
pop-up message for the call tells the user that the incoming call
is on their private line.
- Calls to the private telephone line always ring through. They
do not follow "do not disturb" rules.
- Private telephone lines are inbound only and cannot be used to
make outgoing calls. When a user with a private telephone line
makes a call, the call originates from the user’s primary telephone
line and does not hide the user’s name or the user’s primary
telephone number from the person called.
How Private Telephone Lines Are Similar to Primary Telephone Lines
- Unanswered calls to a private telephone line are routed to the
same voicemail inbox as for the primary telephone line (if
voicemail is enabled).
- Call park and call pickup work with private telephone lines in
exactly the same manner as they do with the user’s primary
- When simultaneous ringing is enabled on a user’s primary
telephone line, it is also enabled on the private telephone
- The telephone number for a private telephone line is recorded
in the call detail record in the same manner as the telephone
number for a user’s primary telephone line, but with an indication
that it is a private telephone number.
- After a user answers a call on a private telephone line, the
call is treated the same as a call on the user’s primary telephone
line. For example, if a user who receives a call on a private
telephone line forwards the call or invites others to a conference
call, the user’s name appears in Communicator "14", and the
telephone number for the user’s primary telephone line appears in
- When a user deflects calls from their primary telephone line to
another telephone line (for example, to a mobile or home
telephone), calls to the private telephone line are also
Note: When a call to a private line is routed to an alternate telephone number, the telephone number for the private telephone line is made available to the alternate telephone number and may be displayed in the logs for that number.
Administering Private Telephone Lines
In addition to the technical aspects of creating and managing private telephone lines, you will need to establish administrative procedures for them. This includes determining policies for who in the organization is eligible for a private line, creating and maintaining lists of people and their telephone lines (particularly since the telephone numbers for private telephone lines are not stored in Active Directory), possibly creating a private telephone directory for executives, arranging for user training, and related tasks.
Assigning Telephone Numbers
Accounts for new users who need private telephone lines are created in the same manner as accounts without private telephone lines, using Communications Server Control Panel or Communications Server Management Shell.
Use the Set-CsUser cmdlet in the Communications Server Management Shell to assign a telephone number to a private telephone line for a user, for example, Set-CsUser -Identity "sip:email@example.com" -PrivateLine "Tel:+14255551212".
Telephone numbers for private telephone lines can be between 3 and 15 numbers in length and must be preceded with the "TEL:" prefix. They can have any area code and any country code as long as your organization has direct inward dialing for that area code and country code.
For more information about cmdlets and Communications Server Management Shell, see Communications Server Management Shell.
Private Telephone Lines in Mixed Deployments
Private telephone lines should be configured only for deployments of Communications Server 2010. In a deployment in which there are both Communications Server 2010 and Office Communications Server 2007 or Office Communications Server 2007 R2 servers, when a user on earlier version attempts to call a private telephone line, routing of the call fails because the server cannot perform a reverse number lookup on a private telephone line.