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IP Trunking and Your Network

Wednesday, September 30, 2015 - 10:15
IP Trunking Your Network

Now that VoIP solutions have gone mainstream in today’s consumer market, more businesses than ever are pondering the ways in which VoIP can be implemented at their locations, as well as any potential benefits. While VoIP is now being used in millions of homes, enterprises are taking VoIP a step further through IP Trunking. IP trunking allows businesses to use their one internet data connection to communicate with the rest of the world, dividing it among all of their computers, phone lines, and calling services such as call-forwarding, call-waiting, and voicemail.

What is IP Trunking?

IP trunking can be defined as the large-scale, corporate, industrial or institutional use of VoIP.With both VoIP and IP trunking, voice is translated into bytes and run across data lines as opposed to electrical impulses transmitted over traditional telephone landlines. Furthermore, IP trunking can be implemented using public internet options or via the cloud. In this situation, the cloud service provider harnesses the power of their extended private network of computers, servers, and networking equipment, to deploy the company’s calls. The cloud computing setup replaces traditional telephony’s line-to-line switching methods.

How Does IP Trunking Work?

IP trunking works behind the scenes to make better use of your network’s VoIP framework.  Essentially, your service provider runs the trunking service through a circuit that makes a connection between both the sending and receiving switches for each call. Because of the larger “internet pipe” that is available through high-speed internet connections, multiple calls can be transmitted simultaneously – the ideal solution for a corporate communications plan.

Basically, the same VoIP trunk or network connects all users – whether located in the office or at a remote location – to the converged data and voice network. In this arrangement, all office phones are configured to send digital signals through user computers to a piece of telephony called a PBX (Privacy Branch Exchange).

As users speak into their office phones, the trunking program on each computer digitizes the voice signals and converts them to an IP (Internet Protocol) data packet. The trunking program then addresses and routes each data packet to the receiving PBX system – in other words, the person on the other end of the phone call. To finish the transmission process, the routing takes place through each endpoint’s unique IP address; then, the service provider’s network finally sends the packet across the internet to reach its final destination – prior to converting the data back into a voice signal. Turning voice calls into digital data calls allows the calls to be compressed, so that more data can be transmitted concurrently – whether it originated as voice or data signals (since data transmissions take up less bandwidth).


What is a SIP (Session Initiation Protocol) Trunk?

Expanding on IP trunks, we have another trunk connection called a SIP trunk. A SIP trunk isdefined as a direct connection between your organization and an ITSP (Internet Telephony Service Provider).

How do SIP trunks compare to IP Trunks?

SIP trunks are different from IP trunking PBXs in that they can transmit all forms of media – like conferencing sessions, emails or other data, instant messages, presence, and videos – not just voice. SIP trunks allow real-time communications to take place, in addition to simply transmitting static data. Because they were designed to work in a data network and have the capability to extend beyond voice, SIP trunks are more flexible and cost-effective than IP trunks. SIP trunks enable an enterprise to extend its VoIP network beyond the company firewall, without requiring additional equipment, such as an IP-PSTN (Public Switched Telephone Network) gateway. SIP trunking is easier to configure and less expensive to design, operate, maintain, and upgrade, because ITSPs deliver services at substantial savings. Table 1 below shows a comparison of available SIP trunking connectivity options.

Sip Trunk Connection Types

Summarized Benefits of IP Trunking Implementation

The convergence of your voice and data networks means less equipment and support costs, generating savings to your organization.


  • You can save by bundling costs and receiving flat rates from service providers.
  • With a SIP trunk connected directly to an Internet Telephony Service Provider (ITSP), you can get rid of costly Basic Rate Interfaces (BRIs) and Primary Rate Interfaces (PRIs), resulting in an overall reduction in the general service rate.
  • With SIP trunking you don’t need to buy lines in blocks of 24 or 32. Instead, you can buy the bandwidth you need, in smaller increments, and at better prices.
  • Because VoIP and IP trunks convert voice signals to data, the voice calls are technically not using phone lines to make long-distance calls, they are only transmitting data, so long-distance charges can drop significantly – to about $20 to $30 per trunk a month.
  • Multiple locations can use the same trunk, since trunks can accommodate remote data transfers – so there is no need to pay for multiple IP trunking servers.

Business Continuity/Disaster Recovery:

  • If landlines ever go down, but the Internet is still up, you can simply enable VoIP-based calling to immediately resume your communications capabilities.

Reduction in Required Voice Equipment:

  • Since SIP trunks connect directly to the ITSP, there is no need for IP-PSTN gateways, as well as any associated support costs or requirements.
  • Convergence of data and voice networks means that network infrastructure redundancy is eliminated in cabling, switches, and the like.

A SIP Trunking Solution to Fit Your Network

For companies looking to reduce the costs of telephony through the deployment of SIP trunking services, West Unified Communications offers a fully-managed solution. MaxxConnect is a suite of IP trunking solutions designed to provide enterprise clients with the carrier–grade service they have come to expect from traditional providers, along with the benefits of next–generation IP–based service that allows their business to run more efficiently.

This complete SIP trunking solution delivers a consistent set of voice services across your enterprise infrastructure, with flexible IP and TDM Trunking options for your on–site PBX. MaxxConnect is delivered over virtually any MPLS network, providing the efficiency and economic benefits of network convergence, while eliminating the need for local PSTN gateways and costly PRIs.

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