Global SIP trunking

Session Initiation Protocol (SIP) is a digital way to make and receive phone calls and other forms of cloud-based communication over an Internet Protocol (IP) network.

Communications platforms like virtual phone systems, unified communications, and contact center software use SIP to talk to one another over the internet. Organizations and consumers alike use SIP to create, manage, and terminate calls (or sessions).

SIP Trunking is one way to place voice calls and send digital communications over the internet.

SIP trunking services allow us to make Voice over Internet Protocol (VoIP) calls, send SMS/MMS messages, place 911/emergency calls, and use other SIP-based real-time communications.

The primary benefits of SIP trunks compared to Primary Rate Interface (PRI) are cost savings, cloud flexibility, and scale. Because SIP trunks are elastic, businesses can scale SIP services up and down to meet demand easily.

In addition, cloud-based voice like SIP removes the need for fixed overhead costs and on-premise equipment. The infrastructure costs for SIP trunking are also lower because SIP eliminates the need for primary rate interfaces (PRIs), which requires enterprises to buy lines in bundles. PRI customers who need 10 lines have to buy a larger bundle, leaving the rest unused. SIP trunking, however, can be purchased in whatever number of units a business requires.

SIP trunking allows businesses to converge networks because it’s an application, not a service. Just as copper lines transmit signals instead of creating them, SIP allows any endpoint to communicate with another, as long as the two endpoints both agree to use SIP. That means a single-location company can converge its networks, roles, and equipment into one system that meets all of its communication needs.

An on-demand capacity model is called elastic SIP trunking. It’s the ability to scale call channels up during peak demand and offload them when volume drops, without buying fixed infrastructure. Unlike PRI lines which require businesses to purchase in bundles, elastic SIP trunks let enterprises add or reduce capacity anytime. For businesses managing seasonal peaks, rapid expansion, or multi-site operations, elastic SIP trunking is more cost-effective.

Speed, agility, and leanness are guiding principles for companies that need to stay competitive today. To support those principles, businesses need technology, like SIP trunking, that supports them. The benefits of SIP trunking include:

• Unlimited call capacity: SIP trunking gives you unlimited, simultaneous call capacity so you can get concurrent calls to and from a single number. 
• Flexibility: Because phone numbers associated with SIP services are virtual, you don’t need to be tied to your physical location, except where regulations require this. This lets you use DID numbers and SIP trunks for a two-way voice service from your office in New York City, even though you don’t actually have an office in New York City.
• Scalability: SIP trunks bring flexibility and control to your business phone system, especially for larger enterprises. In these scenarios, your dedicated data circuits serve as the backbone for seamless communication.
• Cost savings: Cost savings: SIP trunking typically delivers significant cost savings over traditional analog circuits. Some enterprises report reductions of 50-60% after eliminating PRI bundles and on-premise equipment costs.
• Direct-to-provider control: By leveraging SIP trunks over dedicated data circuits, you actually gain more control over your business phone system. As you expand to new domestic or international locations, you can manage and control your own resources.

A hosted PBX is typically more cost-effective for small businesses that don’t have the resources or expertise to manage on-site PBX hardware. However, SIP trunking is often better if a company already has on-site PBX hardware, and wants greater control and customization options. 

Businesses should look for a SIP trunking provider if they want the added benefits of virtual circuits and flexible pricing options. This system is often referred to as an IP-PBX (Internet Protocol Private Branch Exchange). Coupled with SIP trunks, an IP-PBX serves up similar features to hosted solutions. SIP trunks typically save a business customer money over a hosted solution in that a SIP trunk can serve the needs of three to four employees, while a hosted seat is needed for each employee.

Today, many companies use SIP trunking to power the voice calling within their UCaaS and CCaaS platforms. However, SIP Trunk services can work with any SIP-ready hosted PBX system. SIP Trunks can also be made to work with a traditional analog or key phone system with an IAD (Integrated Access Device).

With all the advantages that SIP trunking offers, why do any companies still use traditional services? It’s simple. Traditional telecom has been in existence for over 100 years. Over its lifetime, copper has been widely adopted, of course, and it’s the telephone technology that most of us grew up using. The short answer is: it was the best option that businesses have had until recent years. SIP trunking is only about 10 years old. That means it was purpose-built to work in today’s business environment. 

Since the advent of SIP trunking as a business tool, nearly 70% of decision-makers have adopted SIP, and of those adopters, 96% report satisfaction with call quality. A protocol can only achieve widespread adoption when it’s based on consistent standards. The guidelines for how a SIP trunk should work and interoperate with a phone system are defined and guided by the SIP Forum, an organization of telecom experts who work toward the continual improvement of SIP standards.

BYOC (Bring Your Own Carrier) allows enterprises to connect a carrier of their choice—like Bandwidth–to a UCaaS or CCaaS platform rather than using the platform’s default calling plans. This gives businesses direct control over call quality, pricing, and disaster recovery. Bandwidth supports BYOC integrations with Microsoft Teams Direct Routing, Zoom Phone, Genesys Cloud CX, Webex Calling, and others.

Network ownership does matter, particularly for larger organizations with higher call volumes. It’s critical to pick a SIP Trunking provider that is an actual carrier with ownership of the underlying network. This will allow the enterprise to maintain greater control and visibility into their SIP trunking services, as well as go directly to the source for resolution if there are ever issues or disruptions in service.

While most SIP providers are resellers that rely on several carriers, Bandwidth gives you direct-to-carrier access, meaning we cut out the middleman, giving you better support with deeper insights and faster results. Industry leaders such as Google & Microsoft rely on a stability that only an owner of PSTN infrastructure can provide. Bandwidth is a CLEC and has National Operator status in 30+ countries, meaning we’re licensed by regulatory authorities in these countries to own and operate our own network infrastructure within that country rather than leasing capacity from another carrier to deliver services.