Understanding Global Voice for Twilio: All Your Options In One Place
There’s no understating the growth and strength of the CPaaS (communications platform as a service) market in recent years.
According to Insight Ace Analytic, the CPaaS market is valued at $15.26bn and expected to grow to $119.61bn by 2031.
There’s no bigger competitor or, in fact, protagonist, than Twilio. Often cited as the pioneer of CPaaS, Twilio’s position in the market includes around a 35% share in total.
Businesses choose Twilio for three main reasons:
- Developer-friendliness: Due to its customizability, Twilio is a favorite with developers.
- API-first approach: When you need to integrate complex technologies, Twilio lets you build from scratch or select templated integrations as a base.
- First to market: A legacy in such modern technology speaks volumes. Twilio is synonymous with CPaaS and full of glowing testimonials and success stories.
With Twilio dominating the CPaaS market, and set to for years to come, it’s vital your underlying voice connectivity supports the great functionality you build on top of it. Without a stable and high-performing network, your telephony (and indeed all other channels) can’t perform to its potential with Twilio.
In this blog post, we’re going to introduce how Twilio works, options for deploying global telephony with Twilio, and the considerations every business must factor in when rolling out across the globe.
Understanding Twilio's Platform
Deploying telephony through your Twilio environment is just the starting point. When you need to create a customizable communications platform without locking yourself into long-term contracts or oversubscribing to too much functionality, Twilio (and most CPaaS platforms) allows you to develop exactly what you need.
What is CPaaS?
“CPaaS offers application leaders a cloud-based, multilayered middleware on which they can develop, run and distribute communications software. The platform offers APIs and integrated development environments that simplify the integration of communications capabilities (for example, voice, messaging and video) into applications, services or business processes.”
That’s the definition provided by industry guiding lights, Gartner.
In layperson’s terms, CPaaS provides a cloud-based platform that helps developers create and manage their own communication platform. It includes APIs and development areas that make it easy to build your own platform with features like voice calls, messaging, video, and custom workflows.
As a leader in CPaaS, Twilio is packed with a variety of channels for you to enable.
Twilio's core offerings
Twilio provides five main channels when creating your own communication platform:
- Programmable Voice: Enabling PSTN calls via web or mobile apps.
- SMS/Messaging: Enabling two-way messaging via a single API.
- Video: Programmable two-way video calling to add to your web or mobile app.
- Email: Sending transactional or one-way emails with ongoing delivery optimization.
- IoT: Connect devices to cellular networks for collection, sharing, and monitoring of data.
Twilio also offers peripheral channels for text-based services like web chat, fax, Twitter, Google RCS, Facebook Messenger, and Line.
Twilio Voice Connectivity Options
There are three standard choices for connectivity when enabling Twilio telephony, alongside any other channels you may choose to enable.
Let’s review which options are best suited for different scenarios and businesses.
1 - Direct Twilio numbers
Opting for a direct connection means you leverage Twilio’s SIP technology to keep everything in-house.
| All services contracted via a single provider | Reliant on a single vendor for uptime |
| In-house support for entire technology setup | Reliant on a single vendor for support |
| Visibility of total network topology | Limitations on geographical coverage |
| Large customers benefit from account management | Large migration project if relationship sours |
Coverage areas
While Twilio suggests it provides “global” coverage, each vendor has its own definition of what global really means.
Twilio provides comprehensive PSTN connectivity in the following areas:
- North America: Includes major locales across the United States and Canada, with primary focus areas reflecting high-density communication infrastructure regions.
- South America: Key locales encompass Brazil and Argentina, among others.
- Europe: Covers 32 locales, including the UK, Germany, France, Spain, and Italy.
- Asia: Features significant coverage in locales within India, China, Japan, and additional prominent regions.
- Oceania: Encompasses Australia and New Zealand.
- Africa & Middle East: Services extend to critical locales such as South Africa, UAE, Saudi Arabia, Egypt, Nigeria, Morocco, and Kenya.
In these areas, Twilio SIP guarantees a 99.95% availability SLA. If you need higher availability, Twilio supports a Bring Your Own Carrier (BYOC) approach where you can appoint a vendor who supports voice connectivity for Twilio telephony in your specific geographical area. (More on these in the next section.)
As you can see, there are significant gaps:
- Asia: Roughly 30% coverage
- South America: Roughly 30% coverage
- Africa/Middle East: Roughly 10% coverage
- Europe: Some parts still missing/not fully supported and only accept voice termination
Using the BYOC approach, you can find vendors with wider geographical reach to help you with international Twilio telephony projects.
Number types available
Twilio provides local, toll-free, and mobile numbers across its supported geographies:
- Local and national: Acquire local and national voice-capable phone numbers.
- Mobile: Acquire mobile voice-capable phone numbers.
- Toll-free: Buy Twilio toll‑Free numbers in the U.S., Canada, and the U.K., or port your existing numbers from 27 supported countries. Twilio also supports “non-standard porting from unsupported countries” but can’t guarantee a successful port.
It can also send outbound calls to nearly 200 locales, with guaranteed route coverage provided by at least four terminating carriers. In this model, however, receiving incoming calls isn’t supported. For two-way PSTN calling in unsupported locations, you will need a separate voice partner.
Pricing structure
Direct Twilio SIP pricing starts with basic pay-as-you-go models, where you pay per voice call you make:
- Starts at $0.0085/min to receive a local call.
- Starts at $0.014/min to make a local call.
For large volumes, you can unlock discounts based on usage thresholds. I.e. The more you use, the larger the discount.
At the end of the scale, you can even commit to specific usage, benefitting from the largest discount available.
2 - BYOC (Bring Your Own Carrier)
The good news is that Twilio welcomes third-party vendors to enable Twilio telephony with their underlying connectivity.
Here’s the statement from its website:
“Using Twilio’s SIP Interfaces, you can take advantage of Twilio’s Voice API with numbers on another carrier. Let’s say you have a great relationship and a ton of numbers with your local provider, or you need new numbers in a country we don’t cover (yet).”
BYOC works by connecting external SIP trunks to the Twilio platform. This takes a little setting up, but pays dividends when it comes to enabling international rollouts.
In Twilio, you’ll need to authenticate the SIP traffic via an IP Allow list. Setting up the voice connectivity side means speaking to your preferred vendor, who should be versed in connecting its PSTN traffic to Twilio’s programmable voice platform.
Benefits of SIP trunking
Global coverage
The main use case for using the BYOC connectivity route is the extended geographic coverage.
With AVOXI, for example, you get support for over 150 countries and connection only requires a new SIP trunk.
You benefit from AVOXI’s established network of Tier 1 carriers to ensure redundant and high quality voice call routing. Plus, AVOXI’s long tenure of relationships with carriers in local markets means you are getting the best possible rates.
Setting up SIP integration is simple. For business admins, follow these simple steps to begin forwarding your AVOXI voice calls via SIP.
Enhanced uptime
Backed by a 4.49 MOS and 99.995% uptime, AVOXI consistently scores above the global benchmark for exceptional call quality.
Compared to Twilio’s in-house availability SLA of 99.95%, you’re getting a more reliable service when you choose the right voice carrier to support your needs.
No porting delays
By opting to keep your existing carrier and integrate its SIP with Twilio telephony, you remove the need to port your numbers. This not only saves weeks of delays, but it also reduces the risk of downtime.
Simplified regulatory requirements
When there are compliance needs to address in hard-to-reach countries, it can take considerable time and effort to prepare your numbers to port and best prepare your network in accordance with local requirements. Choosing to connect a new SIP trunk via the BYOC method is an effective workaround here.
When to consider BYOC
Consider Twilio BYOC when:
-
- International coverage and number types aren’t supported by Twilio SIP directly
- You want a single provider across the globe
- Twilio doesn’t offer direct SIP integrations into your contact center or unified communications platform of choice
- Specific regulatory requirements are hard to manage
- Delays in porting numbers will cause a considerable hold up
- Third-party carriers offer more competitive call rates in your most-called countries
3 - Call forwarding approach
For temporary or small-scale calling needs, SIP forwarding allows you to leverage the customizability of Twilio while benefiting from a third-party carrier’s voice service and number availability in hard-to-reach locations.
A standard approach here is to purchase new international numbers, where Twilio doesn’t support direct connectivity, and forward them to the number that needs to handle incoming calls.
With AVOXI’s SIP forwarding service, you can then customize the following:
- Caller ID configuration (pass through, number dialed, blocked)
- International DTMF tones
- Auto answer prevention
- Language settings
Use cases
SIP call forwarding may be the best option when:
- There are expensive setup charges for new international numbers
- You need temporary numbers in geographic areas not supported by Twilio
- You wish to display geographic flexibility without complete in-country setup
- You need to follow local laws by having local numbers that route internationally
Limitations
The major limitation of SIP forwarding is that this method only supports inbound calling. This is not a solution for outbound or two-way international voice when using Twilio telephony.
When dealing with complex IVRs, call routing, and call center setups, introducing another layer of forwarding may conflict with existing plans and need reconfiguration.
There may also be certain regulatory requirements that don’t allow SIP call forwarding and dictate genuine in-country service instead.
Cost considerations
Diverting international calls becomes expensive at scale and isn’t recommended for long-term or use.
There may be exceptions here. If you need to provide an international number for compliance purposes, but expect zero to minimal calls, this may prove the best solution long term. However, you run the risk of people calling that number and incurring charges.
Making the Right Choice for Your Business
Use the guidance below to help decide which of direct Twilio SIP, BYOC, or call forwarding is best for your business.
| Development resources | While Twilio is great for custom development, factor in resources/vendor support needed for telecoms and network capacity changes too. |
| Geographic needs | If you need to provide two-way PSTN calling in countries not supported by Twilio, you must use the BYOC or call forwarding approach. |
| Call volume | For large inbound call volume, call forwarding isn’t cost-effective. Consider Twilio volume discounts or existing vendor packages via BYOC. |
| Quality requirements | Find a provider versed in reliable, international coverage if you require higher than Twilio’s 99.95% availability SLA. |
| Porting complexity | International porting can be high-risk or cause prolonged delays. |
| Feature set | If a third party offers advanced features, consider the benefit of these versus Twilio’s custom configuration. |
| Vendor lock-in risk | Weigh up the pros and cons of having a single vendor versus distributed telecoms providers. |
AVOXI for Twilio
When you choose AVOXI to power Twilio telephony, you benefit from a guaranteed SIP connection and an uptime SLA of 99.995% and a MoS score of 4.2
AVOXI consistently scores above the global benchmark for exceptional call quality. And our coverage extends to over 150 countries around the world.
AXOVI extends the reach of Twilio telephony:
- 150+ countries across all continents
- International toll-free: 133 Countries
- Local DID: 90 Countries
- Two-way local caller ID: 100 Countries
- UIFN: 62 Countries
What’s more, you can lean on our expert support and guidance for implementation and ongoing management.
It’s yet another reason why customers love AVOXI.
“AVOXI has helped us grow our business across the globe. As we expand into new countries, we just get a new number from AVOXI. They make it simple and cost-effective. Service is amazing. We highly recommend using them.”
- Brad Taylor, President of Blue Summit Technologies.
So if you need help with…
- Superior call quality
- Worldwide reliability
- Preparing your number inventory
- Finding suitable pricing with flexible billing options
- Planning call routing ready to turn off call forwarding
Then you need AVOXI.
Ready to expand your Twilio telephony reach? Learn more about AVOXI’s Twilio SIP integration here.
