Whilst ESP Projects install and maintain various telephone systems across the UK, by far our favourite is Kerio Operator.  Kerio Operator is effectively an IP PBX.  It is built on the popular Asterisk platform but has been tailored to Kerio’s customer base massively; the idea is that it is easy to administer and to use from a customer’s perspective.  Some information about the platform is provided below.

Kerio Operator System Features

Telephone call routing

  • Ringing groups that send inbound calls to all extensions in a particular department (it’s possible to link this to an Auto-Attendant, see below)
  • Telephone call forwarding; routing calls to different offices or mobile phones when a person is out of the office
  • Separate ringtones for local, external and ringing groups, meaning you can easily tell what type of call is coming in (you can also display names rather than numbers on handsets)
  • Customised call-queues and automatic routing of calls as well as audio messaging.

Telephone call handling

  • Multiple Auto-Attendants to automatically answer calls and route them to the correct department, as well as playing custom audio greetings and options etc.
  • Out-of-office and holidays system, providing defined rules and menu structures
  • Telephone call pickup to allow users to pick up calls ringing at another person’s station
  • Telephone paging, providing the ability to call someone directly on their loudspeaker, this can be done to 1 handset or multiples, giving the ability to quickly get notifications out to all people in the building
  • BLF (or Busy Lamp Field) support that allows users to see who else is on the phone at the glance of their handset
  • Telephone call monitoring, allowing users with a particular access code to listen in (or speak) on someone else’s call (this can be useful to supervisors providing training to other members of the team).

User productivity

  • Voicemail to email support, meaning staff can pick up their voicemails whilst out and about using their mobile phone/laptop
  • Kerio Operator Softphone – turns a users mobile into a VoIP phone so that other staff can ring them on their internal extension and the call will ring on the persons mobile
  • Dynamic voice conference calls – allows staff to create conference calls without having to predefine the details
  • Fax-to-email providing organisations with the ability to send and receive faxes directly to and from staff inboxes
  • Web browser access to your phone, giving the ability to listen to voicemails, or even dial numbers, directly from your computer and the handset on your desktop will make the call
  • Shared contacts directory – allowing staff to share telephone numbers and extensions across the business, meaning only one database has to be kept up to date
  • Telephone call recording on incoming or outgoing telephone calls
  • Speed-dial system for frequently dialled numbers.

VoIP security

  • Password guessing protection that blocks IP traffic if they fail to login after a number of attempts
  • Unusual behaviour detection to alert administrators to potential problems.


  • Easy web-based interface
  • Real-time reporting on major issues such as system health and live calls
  • Auto-configuration / provisioning when a new telephone is plugged in
  • Auto-assignment of IP addresses to VoIP devices (where required)
  • Automatic backup of the phone system to the cloud.


  • Call logging statistics can be provided on a web page, which is very easy to use.  Wallboards can then be put up around your business to give valuable insight into how teams are performing. These features are added at an additional cost.


  • Conferencing handsets useful for boardrooms and larger meeting rooms to allow multiple people to contribute all from a single room
  • Video calling – additional handsets required, but the platform fully supports video calling.

Want to know more?

If you are interested in the Kerio Operator system for your business, ESP Projects can provide consultation, installation, training and maintenance. Why not give us a call or Contact Us.