Hot desking: cloud booking or on-premises EM?

Hybrid work has turned the assigned desk into the exception. Whether you call it hot desking, hoteling or flex working, the question for IT is the same: how does a phone become my phone the moment I sit down? Cisco now offers two answers, depending on where your calling platform runs.

Two Cisco routes to a shared desk

	Webex Calling (cloud)	Unified CM (on-premises)
Feature name	Hot desking	Extension Mobility
Desk reservation	Cisco Spaces, Outlook/Google calendar or third-party booking apps	Not built in; separate booking tool
Phone sign-in	Webex app QR scan, pairing code, or voice portal (*30)	User ID + PIN on the phone keypad
Personal settings	Lines and settings follow the user	Device profile with lines, speed dials, services
Sign-out	When the booking expires	Manual, or via a configured time-out

Cisco has invested steadily in the cloud route. Since PhoneOS 3.3 hot desking sign-in no longer requires a reboot, and since PhoneOS 3.6 (November 2025) only the user who reserved a desk through Cisco Spaces can sign in on it. Cisco Spaces Smart Desking lets employees book desks up to 14 days ahead and check in with a QR code.

The gap for on-premises customers

Many organizations in banking, government and healthcare keep their calling on CUCM for security, compliance or integration reasons. For them, Extension Mobility is the

Extension Mobility vs hot desking

hot desking engine, and it works well. Its weak spot is the sign-in itself: typing a user ID and PIN on a keypad is slow, easily skipped, and a common reason employees remain reachable on the wrong desk, or not at all.

Single sign-on closes that gap

ALM Pro links Extension Mobility to the Windows login. When an employee signs in on a laptop at a flex desk, the Cisco phone on that desk logs in to their device profile automatically. When they sign out or lock the computer, the phone logs out . Users can also log on by scanning a QR code with their smartphone. No PIN codes, no forgotten logouts, and no change to your CUCM platform.

The result is the same experience Webex Calling users get from hot desking, on the platform you already own.

Running flex desks on CUCM? Try ALM Pro free for 30 days or read how our customers use it.