Telephony replacement: digital lines (VoIP telephony)

BT plans to switch off all analogue telephone services between January 2026 and January 2027 which means the University needs to migrate its critical and analogue lines from the current Chorus telephony service to a chosen alternative solution by the end of 2025.  

The Chorus service contract (provided by ATOS/Mitel) ends in July 2026 and the University is taking this opportunity to move to a new cloud-based supplier.

Leveraging the University's relationship with Microsoft, the preferred new service will be Microsoft Teams Phone.​There are more than 3000 University or college staff already using Teams Phone.

 

Microsoft Teams Phone

Teams Phone (previously referred to as Telephony over Teams at the University) is part of the Microsoft Teams application and offers the user the ability to make and receive telephone calls through their Microsoft Teams client on any device. It also includes other functionality you would expect from a telephony service, for example the ability to transfer calls, receive or leave voicemail messages etc.

What are digital lines?

Digital lines refer to VoIP (Voice Over Internet Protocol) telephony, as opposed to analogue lines that use dedicated copper wiring and network infrastructure.  If you have a Chorus desk phone, this uses VoIP telephony which is a digital line.

What does this mean for my college or department?

All existing Chorus desk phones will be removed and the project will not supply personal handsets or headsets.  

Personal users can use Teams Phone through:

  • their computer’s inbuilt microphone and speaker  
  • a headset (that they might already be using for Teams meetings)  
  • Teams Phone compatible handset (if paid for by their department or college)  
  • the Teams Phone app on their personal mobile phone or tablet  

The table below shows the Teams Phone equivalent for selected activities that might be in use in Chorus:

Chorus  Teams Phone
Hunt Group Call Queue
Pickup Group Call Group
EA Group Call Delegation

 

People in dual roles

People in dual roles may have a personal line and a ‘role-based’ line.  Only one telephone number can be associated with an SSO, so colleges or departments who want to provide a ‘role-based’ line will need to request a Common Area Phone for this purpose.  They will also need to pay for a Shared Area Device licence if they want to use a handset, and they will need to pay for the handset itself.  Alternatively, the ‘role-based’ line can be associated with a Call Queue, which when dialled could deliver the call to the user's ‘personal’ line.  This could remove the requirement for a handset, and the associated costs.  In this scenario voicemails for the personal line would be delivered to the user’s email address, and voicemails for the Call Queue would be left in the mailbox associated with the Queue.  We can set rules on this mailbox to deliver the voicemails to specified Oxford email addresses. 

Transitioning personal lines to Teams Phone

Telephone Coordinators will need to move personal lines to Teams Phone, using Phoneman, at the appropriate time.

Before moving personal lines to Teams Phone, Telephone Coordinators should:

  • ensure users involved in arrangements such as call queues or delegation will be moved at the same time
  • ensure users have been given adequate notice of any changes
  • ensure handsets are available for those users for whom they have agreed to provide them, and that network preparations are complete for those handsets

There are more than 10,000 common area devices in use currently across the collegiate University.   These are handsets located in communal or shared areas allowing more than one person to make or receive calls (for example, receptions areas, porters’ lodges).  The introduction of Teams Phone could result in some of these common areas no longer requiring a physical handset and the table below outlines the options for moving these lines.  If you are unsure about the best solution to use or need further advice, please contact the project team.

Each common area phones (CAP) requires a Shared Area Device licence which is charged annually.

 

Current Chorus configuration Suggested alternative How to achieve this Associated cost  
Common area phone, e.g. lodge/library/lab etc where a phone is required  Teams Desk phone using a Shared Area Device licence 

The project will fund:

  • 1 reception phone (Poly CCX 400) per building for departments
  • 1 lodge phone (Poly CCX 400) per college
  • up to 10% of remaining common area devices (Poly Edge E100), based on current numbers of Chorus shared area phones

It will not fund additional, future or replacement phone purchases

Your network will require configuration, a device will need to be ordered, configured and deployed

Up front hardware cost, future hardware refresh cost   
    
Ongoing Shared Area Device licence fee and line charge under new cost model   

 
Common area phone, eg lodge/library/lab etc where a phone is no longer required   Move the extension to a Teams Call Queue/Autoattendant. Provide Teams Phone to the users who need to answer these calls.  This will facilitate hybrid working
  1. Assign the users who will handle calls Teams in Phoneman  
  2. Complete the Call Queues and Autoattendants’ Service Request
Ongoing annual line charge under new cost model  
Intercoms Reconfigure these devices to talk to a user on Teams   Contact the project team, which will handle these on a case-by-case basis To be determined individually  

 

Transitioning common area line to Teams Phone

Telephone Coordinators will need to move non-people lines to common area lines in Teams Phone, using Phoneman, at the appropriate time.

Before moving non-people lines lines to Teams Phone, Telephone Coordinators should:

  • ensure users have been given adequate notice of any changes 
  • ensure handsets are available
  • ensure network preparations are complete

Call Queues

A Call Queue is similar to a Hunt Group in Chorus.  It allows calls to a single number to be distributed to a group of colleagues. This is managed through the Teams client of the named individual.  To activate, complete the Call Queues and Autoattendants’ Service Request.

AutoAttendant

AutoAttendant provides additional functionality such as welcome messages, time-of-day-routing, and configurable opening hours.  This can be managed in the Teams client of the named individual. To activate, complete the Call Queues and Autoattendants’ Service Request.

Note:

This is the process for transitioning to Teams Phone as part of Tranche 1.  The information might be refined ahead of future tranches.

 

This is an indicative guide to the main steps Telephone Coordinators in Tranche 1 need to undertake to move your college or department to Teams Phone.   

The extent of consultation with colleagues and notice to end users required will be determined by individual colleges and departments. 

Task Guidance/information

At least 6 weeks before go-live

Complete Form 1: Contact information (deadline 29 October, if not before)

n/a

Brief decision-makers and confirm local approach (eg extent of consultation and handset provision) 

Conduct any consultation needed to identify individual needs and capture key information requested by the project in Forms 2 and 3 

At least 5 weeks before go-live

Project provided handset requirements finalised

n/a

Complete Form 2: Devices and disposals (deadline 12 November, if not before)

Phoneman User Guide | IT Help

At least 4 weeks before go-live

Agree with project dates for technical work (network preparation) 

Telephony network preparation | IT Help

Set up account with and order handsets from Avoira  

Teams Phone Supported Devices | IT Help

Communicate change to end-users, for example first countdown email

 TBC

Teams Phone: Getting Started | IT Help

At least 2 weeks before go-live

Request Frodo port to be enabled 

Telephony network preparation | IT Help.

Communicate change to end-users, for example second countdown email

TBC

Teams Phone: Getting Started | IT Help

At least 1 week before go-live

Ensure Frodo port enabled (by Network Operations) 

Telephony network preparation | IT Help.

Ensure Frodo physical cabling completed (by Managed Network Services or local ITSS) 

Telephony network preparation | IT Help.

Ensure all handset deliveries completed  

n/a

Complete Form 3: Chorus VoIP line review and changes (deadline 10 December, if not before)

n/a

Communicate change to end-users, for example third countdown email

TBC

Teams Phone: Getting Started | IT Help

Inform project of go-live date, for it to schedule activation of Call Queues/Autoattendants in Teams Phone n/a

Go-live day

Phoneman – all personal lines moved to Teams Phone 

Phoneman User Guide | IT Help

Phoneman – all common area lines moved to Teams Phone 

Phoneman User Guide | IT Help

Check Call Queues set up in Teams Phone (after lines moved to Teams Phone)

Call Queues and Autoattendants’ Service Request

Teams Phone Using Call Queues | IT Help

Deploy new handsets 

See section below this table

Remove old Chorus handsets  

n/a

Final communication to end-users, for example Go-live email 

TBC

Teams Phone: Getting Started | IT Help

From 1 week after go-live

Raise any support tickets with central IT Service Desk , not the project team n/a

2 weeks after go-live

Gather and package old Chorus handsets to one location ready for collection and disposal n/a

 

Handset deployment process: Tranche 1

  1. Deploy handsets to their required location.  The device should pick up an address in the Teams network subnet associated with your building’s Frodo.  You can check what is in Huginn (available to ITSS via https://www.networks.it.ox.ac.uk/itss/huginn/frodos/)
  2. You then need to:

    1. plug in the device and set the admin password (the default is 789)
    2. accept the Terms & Conditions
    3. set the language
    4. set the time zone
    5. confirm the settings, and the phone will reboot
  3. The handset will boot up and display a URL and a code on the screen.  Note: the handset will log in to the account associated with the browser you’re using
    1. personal phones: browse to the URL and log in with their SSO credentials.  If they are already logged in on the browser, you will not need to perform this step.  Next, enter the code on screen and the user should be logged into the phone.  Note: the code on the phone’s screen only lasts for a few minutes.  If login fails, try refreshing the code on the phone and entering this on the browser you’re using. 
    2. common area phones: use the browser on your laptop or PC to navigate to the URL using a private or incognito window.  Enter the code on the phone’s screen.  When prompted, enter the Common Area Phone username and password supplied.   Details of the username and default password can be found on this document.  On first login, you will need to change the password.  There is no need to retain this password in your records, nor tell the support team what it is
  4. Unplug any Chorus handsets and store ready for collection, otherwise your users will be able to make outbound calls using the same number on two systems which would cause confusion 

Telephone PC pass through process

In some cases, where there is a lack of available network ports, the telephone is used to give network access to PCs and laptops. It is easy to check for this. If the Chorus phone has 2 network cables plugged into it then it is indeed supplying network access to a laptop or PC.  

When it is time to swap the Chorus phone for the new Poly Teams phone, you can ensure both phone and PC continue to work by following the following steps: 

  1. Turn the Chorus phone upside down and identify the port marked 'Network'  
  2. Unplug and retain the cable from that port 
  3. Then remove the other cable from the port labelled 'PC'  
  4. Remove the Chorus phone from the desk and replace it with the new Poly phone 
  5. Plug the cable that was in the port marked 'Network' on the Chorus phone into the left-hand port on the Poly phone (it is embossed with a picture of 3 devices linked together) 
  6. Plug the cable which was in the port labelled 'PC' on the Chorus phone into the right-hand port on the Poly phone (it is embossed with a picture of a PC screen)  

The phone will boot up and PC connectivity to the network will be restored.  

 

Detailed information

Expand All

Date Activity
June to September 2025 Approval of proposed solution (Teams Phone), transition process and schedule, consultation on charging model, support model and pricing information 
June 2025 to April/May 2026  Ascertain college and department requirements for shared area digital lines and equipment
From August 2025 Transition to Teams Phone, facilitation of new equipment purchasing and management of new service
By July 2026 All lines to be retained transitioned to Teams Phone

 

Details of the charging model for Teams Phone are available at Teams Phone Billing | IT Help.   The service will be supported by the Communication and Collaboration Services Team in IT Services. Service Requests will be updated to reflect this over the coming months.

  • Collection of Chorus handsets from individuals and common areas will be the responsibility of each individual college or department.  Where a college or department already has a Stone collection booked, it will be most efficient to use this for disposal of its handsets.  Otherwise, the project will coordinate removal of handsets from a single location for each college/department, and their secure and safe disposal
  • The project will not fund the purchase of headsets or Teams Phone compatible handsets for individual users.  
  • It will provide:

    • one reception phone (Poly CCX 400) per building for departments
    • one lodge phone (Poly CCX 400) per college.
    • up to 10% of remaining common area phones (Poly Edge E100), based on current numbers of Chorus shared area phones
  • It will not fund additional, future or replacement phones

NOTE: Teams Phone can be used without a handset or headset through the computer's inbuilt speaker and microphone.

See indicative costs for Teams Phone compatible handsets on the IT Help website.