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What is VoIP?

What is VoIP?

Many of our partners ask us, “What is VoIP?” and we wanted to give a great, beginners introduction into a major part of todays voice technology. This voice calling technology that has been around since the mid 90s is used by 30% of businesses and in many of the apps we use today, but few people fully understand what VoIP is and how it works. Here’s an epic guide to provide you with everything you need to know, from the different pronunciations to the many perks.

A Brief history of VoIP

Less than two decades old, VoIP has revolutionized communication all around the world”. The first VoIP calls were made by ARPANET in 1974, but the VoIP technology we know and use today was invented by VocalTec in Israel in 1995, starting as a home project and eventually pioneered with the first widely available “InternetPhone”. Soon after the first release, voicemail came about, and a couple years after that, VocalTec created computer-to-phone calling as well as phone-to-phone calling. It was not until the 1990s when hardware prices and the economic climate changed people’s attitudes to voice calls over the Internet and make it seem a sensible choice to cut costs for consumers and businesses. Businesses were looking to cut costs and even today in Africa, voice over the Internet is a great choice to offer great bandwidth at a low cost.

But there were few incentives for using the somewhat redundant technology, with its poor sound quality and “free” calls compromised by series of advertisements. Or so it seemed. In early 2000, the call quality and connectivity improved with the availability of broadband Ethernet. VoIP switching became a thing, and people as well as companies worldwide finally started realizing the benefits of the technology, as operating costs soared. Then came Skype, the company that “forever changed what we wear in front of the computer”. Starting off with voice in 2003, Skype was flexible and attentive to the user demand. After adding video conferencing options a few years later, and through limiting third-party software and hardware, Skype became top-of-mind in a market that has seen a massive growth in just a few years. what is voips traction so far And where’s that market today? VoIP has evolved into the technology that powers many of the communications apps, allowing for much more rich communications including video.

“With the plethora of technological advancements, such as broadband, and later Wi-Fi, capabilities, the integration of phones, computers, and other devices, and the emergence of Skype as a completely revolutionary model for the way people want their communications to operate, VoIP has become an integral part of the day-to-day lives of many people throughout the world and is today one of the most talked-about technologies in the communications industry.” Bebusinessed

A selection of VoIP apps


“This app needs no introduction, it is one of the best VoIP apps for iPhone. For years Skype has been one of the most used VoIP apps in the world. With Skype you can make calls to other Skype user for free. It also let you call conventional phones for very low rates… The best feature of the Skype, which makes it better than other apps in its class, is its Video chat and video conference options. Although many other apps also offer these features, none is as effective as Skype.” Full review at

Facebook Messenger

Offering text, voice message recording, HD calls, snap photos and videos, stickers, group chats, and now video calling for free, Messenger gets four out of five stars in a review from PCWorld, which describes it as a solid IM app with high quality and power. “If you’re a Facebook user, you’ll want this app.”


Highly acclaimed WhatsApp, has been referred to as “the most disruptive force in the history of the telecommunications industry”. PC-Tablet writes that “with crisp sound, a solid connection and WhatsApp’s massive market share, the company is well positioned to become the industry standard for voice calls.” Possible reasons for WhatsApp’s popularity is their first mover advantage, their attentive and user friendly features, and their expansion to other platforms, including Nokia S40 (a non-smartphone platform).


“It’s main focus isn’t actually VoIP or SIP, as it markets itself as a social network…It’s won a number of awards, and the app itself boasts of having “great quality” over 3G, 4G, and Wi-Fi connections. Tango is very easy to use… Unfortunately, you can only communicate with people who have a Tango account, so convincing your friends to get on board might be difficult.” Full review at


Among the pros of KakaoTalk is the unlimited texts and calls, mobile numbers as the only registration, and the huge user base. Among the cons are lack of video and the fact that you can’t reach non-KalkaoTalk users. “KakaoTalk has some more features. The Plus Friend feature allows users to obtain benefits and multimedia content…The app integrates your contact list and adds friends automatically…KakaoTalk actually offers an ID for each user and you use it to identify your friends on the network.” Full review at


“The Viber app lets you text, call and share photos and videos for free using a well-designed interface… Viber automatically syncs with your contacts and knows which of your friends have Viber, making it easy to stay in touch on the cheap. Not only is this app incredibly simple to use, it’s available to more than 200 million users for almost every mobile platform… Overall, Viber is our favorite messaging app.” Full review at

average data use per minuteSource:


A little less conversation, a little more action, please? Here’s a list of 21 hands-on VoIP related tutorials, for the ones who are tired of only talking about talking.

A comparison between VoIP and PSTN

PSTN is like churning: the old way of shaking up cream to make butter. Known for providing reliable communications to its subscribers, PSTN is the traditional and international telephone system, that originally carried analogue voice data through copper wires. Today, it’s digitized but carried over the phone network separately from Internet traffic. PSTN stands for Public Switched Telephone Network, and is also referred to as the Plain Old Telephone Service (POTS). In the early days of PSTN, telephony needed assisting operators, physically and manually connecting pieces of copper wires to one another on a switchboard, in order to to connect every individual phone call. The longer the distance of the call, the more copper wire was required, and therefore, the more expensive the service. From the 60’s and forward, when switching automatized, many calls could share the same line. However, the churned butter will eventually turn bad… VoIP is like modern cooking: using a fast food processor to shake up the cream, and letting the spinning blades do the work. VoIP stands for Voice over Internet Protocol, which means real-time transmissions of voice signals from one IP address to another. It’s a generic term for a set of facilities that sends voice in digital form (voice information travels in discrete packets), enabled either through Ethernet and Wi-Fi, through an analog telephone adapter (ATA) or through a softphone.

VoIP still has some stigma around Internet voice calls and poor quality. This dates back to the 1995/1998 projects that often had poor quality because of the early nature of the technology. Today, many of those problems are extinct.

A step-by-step guide to use VoIP

VoIP is surprisingly simple to use, which might explain why it’s starting to take off in terms of popularity. To use VoIP, here’s what you need to do: 1. Select the VoIP service you’d like to you. Most VoIP services will require you to download their software to your computer; this download is usually free of charge. 2. Once you’ve installed the VoIP provider on your computer, set up your account. This usually includes selecting your location, adding information about yourself (to help any potential in-app contacts find you), and selecting a username. 3. Before making the call, select your computer’s sound card, Internet connection, speakers, and microphone. Some VoIP providers will perform this test for you during the installation process. If everything is working properly, you should be able to make a call to another user. 4. Use the in-app prompts to make your call. Some VoIP providers allow you to click on the username and choose between a voice call and a video chat. If you’d like to call someone outside of the VoIP app, the software might present you with the image of a phone dial, which allows you to input the number of the person you’re calling. Please note that if you don’t have an Internet connection, you won’t be able to use your VoIP software; this includes the ability to make emergency calls. voip flow chart

A list of perks

As over 70% of all mobile communication (and almost 90% of U.S smartphones) flows over WiFi, we’re currently looking at the rise of VoWiFi and VoLTE. Here’s a list of 23 modern VoIP pros, that comes with the mobile wave. VoWiFi growth

Source: The What, Why, When and How of VoWiFi


With VoIP, you can bridge calls between different systems: you can still use/connect to a conventional phone, or any kind of device, which makes the service beneficial whether you’re calling from Europe or Asia. The low level of infrastructure makes VoIP globally adaptable and accepted. voip examples


Because of its universality and a constantly evolving hardware market, VoIP allows you to be more flexible in terms of availability and reach. Are you in front of the computer at your office? Call to/from the PC. In the sofa, watching the latest episode of GoT? Call/to from your tablet. Out for a run? Your smartphone. Ok, you get the point…


This argument is almost worn down, but it’s still the biggest incentive for developing and using VoIP. Compared to using PSTN, no matter how frequently you call, your phone bills will always be somewhere between cheap and free. And the same principle applies to distance. Because VoIP systems are based on adaptive routing (data travels between routers all over the world), all calls are charged as domestic. This way, you can make unlimited long-distance calls without ending up paying a fortune for it. Again, globally adaptable. As for businesses, VoIP is a low initial investment, and the costs for service, maintenance and upgrades are lower. Plus, you can also save loads by not having to pay for travels and pricey hotels when networking with clients… How?


VoIP doesn’t only provide cheap phone calls. It also comes with a great list of additional features (which will be explained separately, a bit further down) that enables business teams to work virtually instead of always having to be geographically co-located. Anything you would do on a regular business meeting can be done through VoIP: negotiating face-to-face, pitching and presenting, signing contracts, or showing each other pictures of your families.


Even though PSTN is still in the lead, VoIP reliability is getting better. Due to the Internet, VoIP can handle heavy call volumes without compromise, and resiliency as well as disaster recovery is better. During upgrades, the adaptive routing makes for minimal downtime and the ability to fall back if an upgrade fails. privacy


Because 2014 was the year of the hacker, the VoIP industry is finally getting serious about security. SRTP, TLS and better implementation approaches are some of the ways which’ll make VoIP systems more secure this year.


For many small businesses, scalability is a main concern. With VoIP, it’s easy to add more subscribers and integrate VoIP with other systems and devices. And there are many features by which you can adjust your communication system to your needs, as your business scales…


Don’t just interact through voice, like you’d do with the plain old telephone system – be able to see each other’s facial expressions and body languages by using video calls instead.


You know the “I just need to call X, and then I’ll call you back”-procedure? Do group calling and talk to several people during the same session, to avoid being the middleman! user community


Marry the two features face and group calling to get its full potential: with VoIP, you can connect a whole bunch of people with both audio and video at the same time. With tools for managing invitations and conversations (raised hands, mutes, etc.), the conversation gets less messy, and voilà, you have a full feathered business meeting arranged.


Another major perk when using VoIP in business, is that you can unify your communications system! Combine asynchronous communication with real-time, and have the same repo for email, IM, voice, video, etc. Allow you and your users to individually choose how to receive, process and send their messages, and avoid all downsides of having a dispersed communications system.


Speaking of which, if your business includes Customer Relationship Management (CRM), you can integrate it with your VoIP system, to streamline your customer interaction, for instance by directly linking the callers to their profiles.


Another type of seamlessness is casually sending over a file through the same system as the one you’re calling from, instead of navigating to various mail systems or file sharing services. This’ll undoubtedly make the interaction more efficient. file sharing


Being a cloud based solution, VoIP is easy to manage. Switch between providers or collect valuable data and track calling history, such as duration, originator, destination and cost from your VoIP provider.


Instead of having to take notes and type like a crazy person during a call, you can just record the whole conversation!


Don’t be that anonymous caller – leave a voicemail. The one you’re trying to reach can choose to transcript your message and receive it as an email, or reversed.


Manage your contacts better with Caller ID: Get rich data about your contacts, identify an unknown caller while the phone is ringing, or get information about the person behind a text or missed calls. In addition, you’ll be able to search for new contacts, make yourself invisible to certain people, or direct calls to certain actions, just as you do with your emails: some are urgent, others can wait, and spammers are just automatically discharged.


A Find me/Follow me (FMFM) functionality lets you create a route of interconnected devices which are configured to automatically run through before the caller reaches your invoice. By for instance calling your office, home and mobile during the same session, 1) the caller doesn’t have to try every number manually, and 2) your stack of “Hey, I tried to reach you at -” voicemails and emails decreases.


Your phone number doesn’t have to be assigned to your area code. Create a virtual phone number, so that your customers feel safe to answer when you’re calling to other countries.


Outsource your receptionist tasks by employing Ruby, or another virtual receptionist. They’ll save you labor costs, route your calls, and keep up the professionalism – even on a rainy Monday.


Integrate your analog door phone with your VoIP system, and you can let delivery guys or co-workers in (you know the ones that always forget their key), without having to run back and forth. Simply lock/unlock through your phone!


You know when you’re in a phone queue, and you hear the dial sound for the millionth time. Or when you’re stuck with the awful elevator music. Well, don’t let your customers go through this. Replace the dial sound with some nice tunes of your own choice, while their on hold. ivr music


In addition, you can play games, catch up, and hang out in a more intimate way than when just talking on the phone. VoIP is getting more social, both in terms of its expansion in features and its presence in social networks. As you probably already know, Google and Facebook has already taken the plunge. What it means? When VoIP gets social, it spreads, and when it spreads, it gets better. In a modern take, VoIP is more than just voice. It can offer your business rich, powerful, enjoyable, secure, easy and cheap communication, for almost no effort. All you have to do is choose the right service provider or implement it in your own app. With at least 23 good arguments, there’s no reason why you shouldn’t take full advantage of the many great opportunities that comes with the modern way of raising your voice.

A final word

If your looking to add VoIP into your app, try Sinch for free today and see how our SDK can enrich your app with in app calling across the world. Signup, read our documentation and try a tutorial to see how easy it is to build with Sinch.