Information Technology Reference
In-Depth Information
So, what happens if you delete an End User who is associated with a device that is associ-
ated with a DN? Nothing. Although the association exists and is important and useful, the
three database entities of User, Device, and DN are independent of each other. The De-
vice and the DN do not go away if the User is deleted, and the same result applies if the
Device or DN are deleted (although a phone without a DN, or a DN without a phone, can't
make calls).
Autoregistration of IP Phones
CUCM includes the Autoregistration feature, which dynamically adds new phones to the
database and allows them to register, including issuing each new phone a DN so it can
place and receive calls. Autoregistration is supported by all Cisco IP Phones.
To enable Autoregistration, perform the following steps:
1.
Verify your Autoregistration Phone Protocol. Access this setting under System > En-
terprise Parameters; choose either SCCP (default) or SIP. Phones that do not support
the chosen protocol will still autoregister using their native protocol.
2.
Verify that at least one CM Group has Autoregistration enabled (by selecting the
checkbox for
Auto-registration Cisco Unified Communications Manager Group
).
3.
Enable and configure autoregistration on one or more CUCM servers within the CM
Group enabled for autoregistration:
Enable Autoregistration by deselecting the
Auto-registration Disabled on this
Cisco Unified Communications Manager
checkbox; it is disabled by default, so
unchecking the box enables it.
■
Configure the range of DNs that will be dynamically and sequentially issued to
auto-registering phones. The default
Starting Directory Number
is 1000; if you
change the
Ending Directory Number
to anything higher than 1000,
Autoregistration is automatically enabled. If you set the Starting and Ending DNs
to the same value, Autoregistration is automatically disabled. (Autoregistration is
disabled by default, because both the Starting and Ending Directory Numbers are
set to 1000.) You will want to choose a range of DNs that fits in well with your
dial plan to avoid overlap and confusion.
■
Set the Partition that will be assigned to the autoregistered DNs. This is optional,
but it is one good way to limit and control autoregistered phones.
■
Verify that the
Auto-registration Disabled on this Cisco Unified
Communications Manager
checkbox is unchecked, and then click
Save
.
■
A simple way to test Autoregistration is to plug in a new phone; if it receives a DN in the
range you specified (or a DN in the range of 1000-1999 if you left it at the defaults),
Autoregistration is working.
Some administrators see Autoregistration as a security weakness, because any IP Phone
will be dynamically added to the database and potentially begin making calls, perhaps
even to the PSTN if it is not restricted. It is common to enable Autoregistration only when
it is needed to prevent the occurrence of “rogue phones.”
