SIP Trunk Providers

What is SIP Trunking?

 SIP stands for Session Initiation Protocol. Trunking is a term that refers to the network of lines and switches required to place phone calls over long distances.

Trunking was first developed to support the installation and use of traditional "land" phone lines. For anyone old enough to remember party lines, originally this technology was quite basic. Then land lines became more sophisticated to allow each caller to have their own dedicated line.

Today, there is an even more sophisticated version of this technology that involves the internet. This is the virtual trunk line - also called SIP Trunking. SIP is the technology that creates a virtual version of the traditional trunk line to enable VoIP to work. The SIP virtual trunk line uses the internet to connect to the main PSTN, or Public Switched Telephone Network, so users can place and receive calls virtually both locally and around the world.

With a traditional phone line, users rely on actual physical phone lines equipped with a series of switches and circuits that relay a phone call from one region to the next until it reaches its intended destination.

The virtual equivalent uses SIP trunk lines run through your IP address to allow phone calls using voice, video and the internet to place calls.

VoIP and PBX technology has allowed phone, video and messaging options to expand far beyond what traditional landline phone service could ever provide. SIP signaling has opened up wonderful new options to connect people for personal and workplace communications.

Best of all, SIP, VoIP and PBX technology has drastically reduced the cost to place and receive phone calls. It has also lifted the restrictions on where those calls can be placed and received from. There is no more having to get to a location where there is a land phone to place and receive calls. Calls in multimedia format can be placed and received from anywhere an internet signal exists.

In terms of cost, any SIP call is classified as a local call regardless of whether the actual number being dialed is local, national or international. Each SIP virtual call connection is made possible by technology called the SIP URI, or unique virtual address.

Most business VoIP packages offer SIP services in addition to other business services tailored to the needs of small, medium or large businesses. SIP VoIP allows even startups and solopreneur ships to launch and maintain a professional yet affordable operation in any area where they wish to do business.

SIP Trunking Overview

With SIP trunking, existing telephone and Unified Communications (UC) connections are made using an existing IP address and network. There is no longer a need for physical trunk lines. SIP trunk lines allow VoIP calls to place and receive calls on any PSTN phone using a hosted PBX system.

There are actually only three required elements for establishing an economical, professional, turnkey SIP VoIP system: a SIP provider (service supplier), a SIP-enabled phone system and a switch or firewall to serve as the border connecting your in-house network to an external IP network.

SIP Trunking Advantages

Imagine a solopreneur working away in their spare bedroom or basement, launching their startup one day at a time. With SIP trunking, no one other than the solopreneur themselves has to ever know they are a one-person operation.

Now imagine an international corporation with offices spread out across the globe. This Fortune 100 company is able to receive, place and route callers all around the world for a price not unlike what the solopreneur is paying.

Best of all, both companies and all the ones in between can have a selection of phone numbers attached to their operations with different area codes and country codes - yet still pay local prices for all of these calls.

This is only possible with SIP VoIP technology.

SIP is flexible

Want to add a line? No problem. No longer need a particular number? Just log in to the dedicated web portal and delete it. In this way, SIP is fast and flexible to keep budgeting lean and competitive everywhere a company does business.

SIP is robust

In an era where unprecedented natural disasters, storms and erratic weather is plaguing traditional landline communications, SIP trunking is able to quickly and seamlessly adapt to changeable weather conditions by simple rerouting calls using available virtual networks.

SIP is affordable

SIP hardware and software is sleek and simple. One small suite of tools can run the solopreneurship or international corporation with equal ease.

SIP is resilient

SIP can use any available internet connection to place or re-route calls depending on the business's needs and operational changes. And existing SIP numbers can travel wherever that business needs to go.

SIP is always available

SIP trunking offers flexible pricing plans to make free international calls.

Business Communications Improve With SIP Trunking

Thanks to new virtual SIP trunking technology, communication options are now limitless. There is never a need to purchase a new land-locked trunk line with more phone lines than the company needs or will ever use.

SIP trunking is also eminently scalable by as little as a single phone number if need be.

SIP trunking can combine everything a business needs to establish and maintain internal and external communications in one single service: video, data, messaging, voice, local, long-distance and international calls, broadband internet and more is routed through a single network.

Dynamic bandwidth also manages web and phone needs in real time to ensure consistent speed and up-time for all required services.

SIP technology could be viewed as the phone equivalent of SaaS (software as a service) since the company has zero requirements or responsibilities for purchasing, installing, updating, repairing and maintaining any type of in-house hardware.

Rather, the SIP provider handles all of those needs and simply activates a SIP proxy server to handle calling needs.

Service outages cease to be concerned with the switch to SIP technology. Even unanticipated power loss requires only an instant reroute to a different satellite office and calling can continue uninterrupted.

This is a particularly advantageous benefit for companies that operate internationally or remotely. There is no longer a need to maintain local offices here, there and everywhere with the connectivity afforded by SIP trunking.

SIP Trunking vs the Alternative

It doesn't take much for the data costs to start adding up with multiple connection lines. But with SIP, all data can be sent through a single connection point.

There is no hardware or software to purchase, install, repair or maintain, removing the need to employ on-site repair technicians or designate office space for the same.

This is why SIP trunking trims costs by approximately 25 percent automatically - and that is without factoring in the lower calling rates and free international calling plans. VoIP to VoIP calling is also free.

PRI (Primary Rate Interface) trunking is the most common alternative to SIP since the technology is older. Many companies are just now beginning to upgrade from PRI to SIP. With the upgrade, companies no longer have to pay for T1 lines to multiple locations. Unlike SIP, PRI trunking can also be impacted by inclement weather.

The SIP vs PRI guide explains more about the differences.

Finding The Best SIP Trunk Solution for Your Needs

SIP providers are not all created equally. Take into consideration the following:

• SIP Network - The best SIP providers host and run their own networks. 

• SIP Security - SIP Security ensures all data and voice transmissions take place behind a robust firewall, anti-fraud encryption and a bulletproof virtual network.

• SIP Number Porting - The top SIP service providers offer the option to port (keep) existing phone numbers even when business logistics change.

• SIP Customer Care - The best SIP providers offer 24/7 access to their customer care and technical support hotlines.

• SIP Pricing - Each SIP provider has the freedom to develop their own customized service packages and offerings. Cheapest isn't always best and most expensive doesn't always mean better.

Getting Started with SIP

SIP success starts with choosing the right resources.

These are the basic requirements to get started with SIP.

1. Router.

2. Firewall.

3. Setup supports translation for port addresses and static mappings for ports.

4. FQDN (fully qualified domain name) that resolves to a static external IP.

5. Bandwidth from 30-120 kb/sec.

VoIP Account Setup

Choose the SIP-compatible VoIP provider that meets your business needs and create your account.

Firewall Test - SIP routing hinges on proper firewall setup and configuration. In particular, the firewall must be compatible with the SIP port and the audio port range.

Activate and Configure Your VoIP Account - VoIP account configuration ensures your SIP trunking service has the right settings for your geographic location(s) and the phone numbers you wish to use.

Create VoIP Account Name - The name you choose for the VoIP account should match with the server hostname and outbound proxy details given by your VoIP provider. The number of simultaneous calls permitted should match the limitations of your plan.

Your IP or VoIP registration details will establish authentication, after which you can route the main number and add each DID number that will be linked to your account. Select and set the main phone number that will be associated with your caller ID.

Set Outbound Rules for Call Routing

SIP service gives you the flexibility to choose what types of calls can be routed through your SIP trunk. These are called "outbound rules" and they must be created at the time you set up your service.

You can route calls through gateways or SIP trunks. Different individuals or groups, numbers or calling codes may be best served by one or the other. Assign permissions to each individual or group, number or calling code.

Set self-explanatory names for each of the outbound calling rules so that each department is clear about what belongs to whom. Clearly state the elements that trigger call routing by department.

Here is an example: For groups of numbers that share a prefix, calls that come in from certain groups of extensions or calls that go out to certain groups of extensions or numbers can be grouped into different elements triggering different rules.

The route dialogue should state three key components: how each outbound call is to be routed, which gateway applies and how each is connected to the SIP trunk.

In some cases, you can also establish a backup or alternate set of outbound rules that will trigger when the primary route set becomes unavailable for some reason. The prepend option is the right tool to use to set up an alternate set of rules for each route that needs a backup.

Along with immediately noticeable overhead reduction and company-wide cost savings, making the choice to switch to SIP trunking will simplify and streamline intra-company communications as well as external customer care and support.

SIP trunking is the voice technology of the future. Opting in now places your company in the forefront to maximize flexibility, resilience and profitability amidst the ongoing uncertainties of the global marketplace.

Be sure to compare SIP trunking providers using the comparison tools above to find the best solution for your company’s needs.