SIP versus ISDN

Posted 7 years ago

SIP is one of the most talked about technologies in the IT industry these days.  The introduction of voice over the internet was predicted (and expected by many) to bring an end to ISDN.  Instead, it has acted more like an upgraded technology. 

SIP, in the early days was always going to be slow on the uptake because bandwidth was very expensive.  As bandwidth costs have become more affordable and new technologies such as FTTC and GEA have been introduced, SIP growth has gathered real momentum.

The argument that you can save money using SIP is potentially a strong one.  SIP has a lower channel cost when compared with ISDN and also, the call rates are normally much cheaper, with some providers bundling calls in with the channel rental cost.  Some providers will even offer QoS for SIP so that issues with voice quality are firmly addressed.  The installation of ISDN is expensive compared to a standard FTTC connection so, in theory, this only adds to the cost savings for adopting SIP.  In addition, the possibility of converging voice and data on the same circuit makes the proposition very attractive to businesses. 

Business continuity is often one of the main topics discussed when considering relying entirely on SIP.  A total loss of service can be avoided by retaining some backup analogue or ISDN connectivity which can be brought into use if required.  Within the SIP provider’s account, you can often configure a failover destination to have incoming calls route over the backup lines automatically.

Telephony fraud, in general, is a real concern and many fear that SIP is more vulnerable to it than ISDN.  This is potentially true, therefore, it is paramount that the Data provider, the SIP provider and the PBX provider all use sensible security principles to ensure unauthorised access to neither the phone system nor the SIP server is possible.

One of the great fraud avoidance methods offered by many SIP providers is in allowing the end user to specify which call types should be allowed and which should be blocked. In addition, real-time notifications of unusual call spending can be sent, reducing potential risk. 

One simple and often over-looked way to reduce the risk of fraud is to ensure PBXs are firmly locked down with firewall rules and with voicemail passwords regularly changed.

The take up of SIP is only going to continue to grow so we should all embrace this technology.

For more information about Abzorbplus+ SIP product, please click here or contact us on 01484 405 300.



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