Save on Costs

Scale effortlessly with a cost-effective solution. Lower maintenance fees, monthly costs, and upgrades allow you to meet business growth.

Customize Your System

Provision as many SIP channels as you need for multiple concurrent calls and DIDs with help from expert engineers.


Access advanced call features, more users, mobility, and a greater integration capacity with ease compared to legacy systems.

What is SIP Trunking?

Smithville Enterprise offers a full range of SIP Trunking services for sending voice and other unified communications services over the Internet. 

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Devices & handsets
Your PBX
SIP Trunk

Why work with us?

  • 100 years of top-ranked service in Indiana
  • We answer your calls in less than 1.5 minutes on average
  • Recommendations based on your needs with technical support available
  • Backed by a guaranteed Fiber network for seamless workflows
  • Reliability you will not experience elsewhere


The main difference between SIP Trunking and Cloud Voice is the PBX equipment. With SIP Trunking, you have your own on-premise PBX equipment. With Cloud Voice, your PBX equipment is hosted by Smithville. All you would have onsite would be your Internet and phones. The maintenance would be done by Smithville. With SIP Trunking, you take care of your own equipment, we just make it VoIP enabled. SIP Trunking requires an in-house IT team to manage the equipment, security strategies, and privacy policies.

SIP Trunking is where a SIP Trunk is installed on your on-site PBX equipment, which allows it to access the internet. This transforms it from an analogue system into a VoIP system. The SIP Trunk replaces older copper-based traditional telephone lines or PRIs (Primary Rate Interface) phone services.

SIP Trunks can have multiple direct inward dailing (DID) numbers and more call features than PRIs. They are typically 25% cheaper than PRI circuits. This is because they elimate additional hardware and overlapping networks.

Sip Trunking is a type of VoIP (Voice Over Internet Protocol), where SIP Trunking brings VoIP phone system capabilities to your existing on-premise PBX equipment. It upgrades an analogue PBX to an IP PBX. Like Cloud Voice, SIP is just one of the possible “protocols” you can use for VoIP communications. It provides a way to convert voice signals into data that can be decoded by devices used by a caller.

SIP Trunking is great for businesses that want more capabilities and less expense from their current PRI systems. If you already have PBX equipment and an IT team, upgrading from PRI to SIP may be your best bet. You might consider Cloud Voice if your business doesn’t already have a PBX system or it needs major repairs or it is too much hassle. With Cloud Voice, you just pay a monthly fee and Smithville will manage everything to do with the PBX.

Any business or site with a high volume of outbound and inbound calls need the flexibility and cost-effectiveness that SIP Trunking provides. For example, call centers, sales, or support hubs, are highly likely to run more complex PBX systems supported by specialist SIP services.

We do still provide PRI services for customers who want to stay on their legacy system. A PRI circuit has a maximum of 23 channels per circuit and one channel for every call happening at a given time. If you need to have the ability for 50 calls to happen all at the same time, then you need 50 channels. For SIP Trunking, you need a minimum of three call channels. Each SIP trunk can host an unlimited amount of call channels.

Something to ask yourself is, “How many calls does the business receive during the busiest time of the day?”

“The Ultimate Business Voice Solution”

Do you have the speed you need to go PBX free?

Test Your Network

This test will simulate VoIP calls for your computer and provide an estimate of how your current Internet service will perform with Cloud Voice.

Learn more and run test Learn more about VoIP and run a test

Note: You must have Smithville Fiber Internet to use Cloud Voice services.

Services you don’t want to miss…

DDoS Protection

Attacks on bandwidth have increased at an alarming rate in recent years. Smithville DDoS Protection filters out the attacks before they even reach you.

Simple, Powerful Security Solution

Replace obsolete equipment and its many disparate parts with Security technology that’s smart, secure and unified into a single system for easy management.

Crystal-clear Unified Voice

Let Smithville host your voice solution for easy administration, a myriad of relevant call features, and always up-to-date technology.

Talk to a business specialist

For more information or to find the best solution for your business, complete this form and a Smithville Business expert will reach out to you.

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