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Understanding Feature Availability
The operation of your Cisco IP Phone and the features available to you may vary, depending on the
call processing agent used by your company and also on how your company’s phone support team has
configured your phone system. Therefore, some of the features included in this Phone Guide might not
be available to you or might work differently on your phone system. Contact your support desk or
system administrator if you have questions about feature operation or availability.
Going On-Hook and Off-Hook
Some phone tasks and instructions differ depending on whether the phone is on-hook or off-hook.
• On-Hook—The phone handset is resting in the cradle, no calls are active, and you do not have an
active dial tone.
• Off-Hook—The phone handset is lifted from the cradle and you have dial tone.
