Modern Day Alternative To ISDN: SIP Trunks

The opinions expressed in this guest post are not necessarily 100 percent in-line with the views of

About this guest author: Viola Allen is a SIP expert and is currently employed with SIP TrunkProviders DotCom. Her passion is to write about the recent technological advancements, including Cloud Hosted PBX and SIP Trunking. Her main motive is to gain more and more information about the latest technological advancements in the industry.

kofoldphoneWe are standing at the dawn of a major industrial revolution where a transition is taking place in the field of Unified Communications. There has been a rapid change in communication flow between businesses in terms of services, technology, connectivity, cost and more. The most important of all these transitions is the evolution of “Trunking Technology”.

Darwin’s theory of “Survival of the Fittest” is also applicable in the field of business communication. The most suitable example to prove this facet is the increasing demand of SIP Trunks. The real implications of SIP Trunk technology are far more than mere communications.

SIP is an Internet Engineering Task Force (IETF) protocol for starting a responsive communication session that comprises of various multimedia elements like games, chats, voice and video, and more. Trunking is a technology by which an organization caters network retrieval to many customers by distributing a set of lines contrary to providing them individually.

Integrating the two, SIP Trunking is a service offered by an Internet Telephony Service Provider (ITSP) that connects a private business class phone system with a Voice over Internet Protocol network.

SIP Trunking Enactment

Depending on the type of PBX solution to be used, SIP Trunk can be enacted in following two ways:-

SIP Trunking with a Legacy PBX

This kind of Trunking is done in enterprises that already have a traditional PBX system. There is a little impetus to seize it all out and replace it with SIP Trunk technology. A portal of VoIP links legacy PBX to SIP Trunks. The call is transfigured to SIP and sent over the IP network to the SIP Trunk provider which finally terminates the call on the PSTN.


1. Voice communications at lower cost.

2. Venture in prevailing communications equipment is retained.

3. No need to spend in new voice hardware.

4. No need to re-instruct the staff for the new system.

5. The end customers still have the same experience as they had with the old set up.

SIP Trunking with an IP-PBX

This mode of SIP Trunking is highly beneficial for new offices where new infrastructure is to be installed. In this version of Trunking, SIP Trunks are provided for IP devices that are SIP enabled hitherto. Intermediate devices may also be utilized for additional features like billing, security, etc.


1. Augmented calling features like priority calling, selective calling, call forwarding and acceptance, voice enabled IVR and more can be validated.

2. Maintenance cost of IP PBX is quite low.

SIP Trunking: Advantages for the Organization

SIP Trunking provides a range of benefits to the enterprise which are as follows:

1.  Total Cost of Enterprise Possession Is Subsided

  • Minimized capital investment- SIP Trunking reduces capital expenditure as it provides a single base for both voice and data transfer. Apart from this, SIP Trunking enables the organization to preserve the investments in existing hardware and increase its functionality, while taking hold of the VoIP services hosted at the headquarters.
  • Minimized long distance call charges- Due to calling traffic, multinational companies face the problem of high long distance call charges. SIP Trunking and least cost routing efficiently lowers this cost and thus saves money.
  • Lower running cost- SIP Trunking converge data and voice transport network. This integration decreases the cost required to run and maintain two different systems. Unlike the legacy system, the addition, alteration and moving of communication channel is easier and less costly through SIP Trunking.

2.  Improved Employee Efficiency

  • Lower mobile phone bills- For employees who are globetrotters, SIP Trunking adds another benefit. It replaces the expenditure incurred in the mobile phone bills due to travelling by communication through universally available internet access.
  • Improved co-operative and conferencing aids- SIP Trunking provides calling features like Unified Communications, worker collaboration and conferencing. In the current scenario of globalization, SIP Trunking allows multimedia conferencing among employees based in all corners of the world. SIP also allows file sharing and supports business applications like Microsoft Office suite, KingSoft Office suite, etc., on a single base, thus enabling high levels of integrity.

3.  Switching To a Redundant Network on Failure of Previous Applications

SIP Trunking via VoIP facilitates an organization to connect to a number of service providers, thus furnishing service redundancy. Availability of a number of service providers assures high level of service availability. Even when one network fails, the other is always there.

Featured images:

Leave a comment

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s