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A SIP trunk is best considered as an IP phone line, similar to existing telephone lines but provided over a broadband connection rather than a typical copper/cable line. Typically SIP Trunks will be supplied as an alternative to ISDN 2 or ISDN 30 lines. A High quality Broadband (ADSL or SDSL) connection will be supplied by 4ward Communications and the required number of SIP trunks will be provisioned onto this connection.

The latest telephone systems typically accept the direct connection of SIP Trunks in the same way as ISDN. Some older systems may need a converter box which enables them to be treated as if they were ISDN circuits. 4ward can advise on preferred converter boxes. SIP trunks typically suit Greenfield phone system installations, i.e. new sites, or existing sites being upgraded for the years to come. SIP trunks significantly reduce the cost of ISDN line rentals but a typical installation may also have ISDN lines as a backup.

For Example:
A site that may have needed 30 channels of ISDN 30, with the associated install and rental costs of the 30 channels could have reduced ISDN channels, maybe 10 as backups or for inbound calls, with 20 SIP channels for outbound calls. The SIP channels installation simply requires a compatible system or converter box and a high quality broadband connection (specifically for voice - data will need additional connectivity).

4ward can provide the SIP trunks and broadband connections and your 4ward authorised distributor can advise you on the best package for you.

Key benefits

  • significantly lower install and rental costs than ISDN
  • Add channels quickly
  • Free calls between 4ward connected group SIP or Featureplus sites