• What is ISDN30?

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ISDN30 is a fixed line scalable telephony platform designed to transmit simultaneous digital data transmissions over an existing standard copper wire PSTN (public switched telephone network). This results in higher quality and more efficient data transfers (e.g. voice, video, text). The service is aimed at medium-to-large scale businesses with more than eight staff.  

ISDN30 provides business organisations with high speed internet connectivity at cost-effective rates. Users with large scale internet and telephony requirements stand to benefit from the ease of scalability built into the service, with more channels made available in line with demand. Channels may be assigned to a single telephone number or to a range of numbers (up to 10).  

What are the benefits of ISDN30?

ISDN stands for Integrated Services Digital Network. The service was introduced as a cost-effective digital alternative to the low-quality inefficiencies of the analogue copper wire PSTN (e.g. loss of voice clarity over long distances). ISDN30 exists to improve the overall data transmission rate across voice, data, text, and applications (e.g. video-telephony).

Benefits of ISDN30 include:

  • Faster data transfer rates
  • Faster secure connection speeds in comparison to modem speeds
  • Multiple concurrent digital channels facilitated through a single copper wire
  • Digital signals are sent over existing telephone lines (separate network not required)
  • Multiple device connectivity through a single line (e.g. fax machines, laptops, PCs, card readers, cash registers, etc.)

As opposed to an analogue connection that would otherwise require all network devices to connect to a modem, ISDN connections instead connect through a terminal adapter (known as a TA). The TA is a device available to consumers in a stand-alone isolated unit format or in the form of a PC card with an S/T interface. 

What are the features of ISDN30?

ISDN30 services support legacy telephony systems, with an eight-channel minimum installation requirement (below eight channels, ISDN2 services may be more suitable - this service has a two channel minimum installation requirement but becomes cost-inefficient when scaling beyond eight channels). ISDN30 is a scalable service ideal for growing companies. 

Features of ISDN30 include:

  • Symmetrical upload/download speeds
  • Call Line Identity Presentation (caller ID)
  • Call Line Identity Restriction (withhold caller ID)
  • Call barring facilities (block selected telephone numbers)
  • High connection speeds for mobile staff and regional offices 
  • Direct Dial In (DDI) telephone numbers for staff (i.e. bypass switchboard)

ISDN30 is supported by a two-channel communication model. The ‘bearer’ channel, or B channel, is responsible for data transmission. The ‘delta’ channel, or D channel, is reserved for signalling and control (data may also be transmitted over the D channel where applicable). The number of each B/D channels and bandwidth available to the user varies with access options.  

Depending on the extent of the subscription service available from the ISDN30 vendor, additional bespoke features may be available. For example, depending on business requirements, the user could benefit from call handling features such as divert on failure (call diversion), diverse routing, and prompt care maintenance.

For further information on how ISDN30 could benefit your business, contact our experienced team of IT professionals for instant advice and guidance.  

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