Fineline: IP Telephone System

Project brief

Fineline was using an ageing Panasonic telephone exchange to provide internal phones, and access to external lines. Although the hardware was still functioning, it did not offer some of the more modern features required in a modern office. In addition, sourcing additional phones was becoming increasingly difficult. It was decided to replace this system with a more modern, IP-based solution.

As part of the initial requirements capture process, the new system needed to offer the following features:

  • Support for 8 lines on an ISDN30e bearer
  • Support for 50 DDIs
  • Desktop phones powered via Ethernet (PoE)
  • Cordless phone
  • Fax-to-email
  • Voicemail for each user
  • Remote site and home working
  • Standard PABX features, e.g. transfer, parking etc.
  • Loud ringing bell for factory floor
  • Night/day service
  • Conference bridge

System implementation

asteriskThe system was designed around the excellent open-source Asterisk VoIP platform. The Asterisk project started in 1999, and has been developed and tested by a global community of thousands. Asterisk today has over a million systems in use in more than 170 countries, including almost all of the US Fortune 1000 companies. It is an enormously capable platform, which provides a rich set of features and significant potential for future functionality upgrades if required.

A standard Dell rackmount server was purchased to host the system, and equipped with a Digium TE121BF card to interface to the ISDN30e line. The card was fitted with an echo cancellation daughterboard to ensure good call quality. A 64-bit version of the openSUSE Linux operating system was installed on the server, and Asterisk was compiled from source.

spa504gFor desk phones, we managed to secure a quantity of Cisco SPA504G phones, which are ideally suited to our factory environment. The phones were connected to the network via a PoE switch, avoiding the need for individual power supplies. A Panasonic KX-TGP500 cordless SIP phone was chosen as the cordless phone platform, connecting to the server via the company Ethernet network.

Each phone is provisioned using the Asterisk provisioning system, which means that adding or reassigning phones is very easy. As users usually occupy the same desks, a phone is assigned to a particular user, rather than the user needing to log in at the beginning of each day.

The system currently supports two remote sites: one involving a number of identical phones, and another running an Asterisk system. Remote phones are provisioned via VPN, whereas IAX trunks are used between the two Asterisk systems.

Contact information is periodically obtained from the company Workspace system, allowing names to be displayed for incoming calls where the number is known to us. A future enhancement will allow users to set up a call by clicking on a link in Workspace.

One of the DDI numbers has traditionally been used to receive faxes. Although faxes are now extremely rare, Asterisk was configured to provide fax-to-email capability. When a fax arrives, it is converted to a PDF document and e-mailed to a distribution group.

As the factory floor contains loud machinery, it is often difficult to hear when a phone is ringing. During core hours, the main incoming line is answered off site, but outside these hours, the factory staff need to be able to hear the phone. A loud ringing bell has been connected to a SIP ATA device, causing it to ring whenever the main incoming line rings. In addition, a custom channel driver has been written to activate a relay and siren – this is only required when all of the machines are running.

Productivity improvements

The new phone system has allowed a number of improvements to take place within the business. Firstly, the ability for all staff to be able to communicate across several sites for free has been enormously beneficial: it is much easier to pick up the phone and talk through a problem now. As more staff have been able to work from home, it has been possible to reclaim office space to add more machinery – effectively allowing the business to expand without increasing the size of the premises. Staff working from home are happier too – they no longer need to work amongst loud machinery and dust.

As with all systems of this kind, it is crucial that they can be expanded and adapted easily to suit the needs of the business. By choosing a well-maintained open-source telephony platform, it is easy to make these changes in future.

Further information

For further information, or to discuss a similar project, please contact Fineline Solutions.