SIP Vs PSTN Vs VoIP

Typically if we want a telephone line for voice calls we would have installed a Public Switched Telephone Network (PSTN) line. A single PSTN line has one telephone number allocated to it and allows 1 call at any one time. To enable more simultaneous calls to be made then additional PSTN lines would need to be installed. Simple and straightforward 1 line 1 call. This works well for home/domestic use or businesses who do not need many lines. The installation costs and service rental charges soon escalate to a point where this is not cost effective or sufficiently feature-rich to offer the services a digital alternate can offer. A PSTN telephone system is now considered outdated telephony, businesses are moving forward towards VoIP & SIP telephone systems, which are cost-effective & feature rich.

ISDN

Where more lines are required or additional features are necessary telephone system providers turn to ISDN (Integrated Services Digital Network). These type of digital line are provided in two formats, ISDN2e and ISDN30 where ISDN2e carries two trunks or ISDN30 carries up to 30 trunks, a minimum order is 8 channels. ISDN telephone systems are still being sold, still relevant, however, when 2025 comes, BT will no longer be supporting ISDN telephony.

But what is a channel?? A channel is a connection which allows a telephone call to take place, therefore, ISDN2e provides up to 2 simultaneous calls at once and ISDN30 with 8 channels provide 8 simultaneous calls. If you have an ISDN telephone system, consider merging this into a VoIP. SIP business telephone system.

ISDN services can be cost-effective where multiple channels are required and additional services such as DDI are also needed. The downside to ISDN is getting the number of lines and therefore trunks correct for the number of calls to be established at peak time. During all other times the investment in telephone services and also hardware to deal with this excess in trunks is costly and unnecessary. ISDN is tried & tested & very reliable, however it will soon be outdated along with business telephone system that work alongside it.

The costs escalate as more lines/channels are required and are installed into a business.

SIP What is SIP? Session Initiation Protocol

It is the protocol computers use to establish a voice or multimedia connection between two endpoints across the Internet. Of course in this context we are referring to telephone calls. Utilising existing broadband services the option is available to substitute traditional telephone services Removal of PSTN and ISDN services remove the bottom line costs from a business. SIP business telephone systems work by using a traditional PBX system, that is virtually hosted, i.e. lines over broadband.

Are the savings really worthwhile?

A Broadband connection per month inclusive of the line is £31.00. A SIP service from CNS starts at £5.50 per month inclusive of 2,000 landline minutes. I’ll let you review your telephone service charges and compare. SIP can be very cost effective for businesses, consider a SIP telephone system today.

CNS can undertake an audit and review of current installations and contracts in place to ascertain if technology changes are suitable for your business.

This was produced by a business telephone systems expert for help with telephone systems contact me!