Written by Kale Haverford Reviewed by James Macey Updated on 2 December 2023 On this page What Is SIP? What’s the Difference Between SIP and VoIP? The Benefits of SIP When Would a VoIP-Only Solution Make More Sense? Next Steps Frequently Asked Questions Expand When seeking a communication solution, some companies think the choice lies between voice-over-internet-protocol (VoIP)—which enables phone calls over the internet—or session initiation protocol (SIP)—which enables other types of communication like video and instant messaging.However, this is a misconception, and it’s not really a matter of SIP vs VoIP. Rather, it’s about how SIP works with VoIP communication systems to scale and offer additional ways to communicate. So if you want more than just the ability to make phone calls, we recommend searching among the best VoIP providers in the UK to find one that also offers SIP. What Is SIP?Established in 1996, SIP is a protocol that facilitates communication over the internet and enables voice calls, video, instant messaging, file sharing, and more. In addition, it both starts and ends the connection between two or more devices, as well as maintaining and modifying the communication session as needed, such as changing a call from audio to video. What’s the Difference Between SIP and VoIP?While frequently used together and sometimes confused for one another, SIP and VoIP are not the same. A VoIP phone service is the actual technology that allows for voice calls to be made over the internet. This is done by converting your voice into data packets that are transmitted through the network.On the other hand, SIP is a protocol that sets up, manages, and ends the communication session itself. VoIP is a fairly broad term, and SIP is one of the many potential protocols that facilitate it.Another difference between SIP and VoIP is that SIP allows for various types of communication, such as video, messaging, and sharing documents. Solutions that are VoIP-only will limit communications to voice calls.SIP is also more versatile and is able to integrate with third-party apps and software, whereas VoIP can’t. As a result, businesses that already use tools like CRM software, calendars, and collaboration apps to operate should consider a solution with SIP protocol to ensure integration is seamless. The Benefits of SIPOne of the main benefits of a VoIP solution that uses the SIP protocol is flexibility. Instead of being locked into only communicating via voice calls, you can offer other options to customers, such as live chat and video calls.It’s flexible when it comes to cost and the pricing plans available, as well. You’ll only have to pay for digital phone lines, and most providers will charge based on how many lines you need, how many calls are made, or even how many minutes you spend on calls.You won’t be stuck paying for extra lines you don’t want or long-distance calls like you would with a traditional phone line. What’s more, you can use existing devices and handhelds, as well as install SIP/VoIP apps on mobile phones and tablets.SIP helps your company scale effectively because it’s easy to add options like video calls as your needs change. Another advantage is that you don’t have to wait for traditional phone line installation if you need to expand.Using this type of solution can also remove a lot of unnecessary complexity in your network. Instead of having to pay for and manage both your data and telephone service, you can combine both into a single network.This can require a relatively strong internet connection but makes managing your networks a lot more straightforward. The exact bandwidth depends on your usage and needs, but it’s a good idea to allocate around 100 kbps per line.Another major benefit is the reliability that SIP provides. Traditional telephone services can easily be interrupted, whether it’s because of someone hitting a telephone pole or bad weather. Even if your internet fails while using SIP/VoIP, calls can often be relayed to another mobile device or landline that’s not connected to the system as a backup.SIP is great for mobile and remote workers, too. As mobile workers are expected to make up half the global workforce by 2028, it’s more important than ever for companies to have the tools and software available to support them.Using a solution with SIP allows mobile and remote workers to remain connected to your communication system, even when they’re in the field. This is done through various apps, and it means they’re reachable on the same number no matter where they are. When Would a VoIP-Only Solution Make More Sense?While SIP is beneficial for most businesses, there are times when a VoIP-only solution is better. For example, if you only have to make voice calls and not use any other type of communication during calls, you mightn’t benefit from SIP.One of the main benefits of VoIP is that it’s generally less expensive than a system that uses SIP. So if you don’t think you’ll use the additional features that SIP provides, a VoIP-only solution can keep your ongoing costs and initial investment low.A VoIP-only solution can also be less complex and more straightforward to manage and maintain. While SIP is not overly complicated, it can be more difficult to configure and deal with due to its different components. Next Steps While VoIP and SIP are often compared to one another, they actually work hand in hand to scale and improve your business communication efforts. SIP is the protocol that allows for different types of communication and data transfer within a VoIP system. VoIP is the overarching technology that lets you make voice calls over the internet in the first place.Now that you know the benefits of SIP and what it provides, consider looking for a VoIP solution with the SIP protocol to improve the communication experience you offer to customers. Frequently Asked Questions Are SIP and VoIP the same? No, but they’re related and work together. VoIP is essentially using the internet to make and receive calls. SIP is often a component of VoIP and allows for other types of multimedia sessions, including video calls or text messaging. SIP is also responsible for starting, managing, and ending the calls themselves. Can you have VoIP without SIP? Yes, if you just need to make and receive voice calls over a broadband internet connection, a VoIP-only solution works just fine. However, if you want to allow for other types of communication like video meetings, file sharing, instant messaging, and others, you need a SIP solution. What happens to VoIP/SIP when the internet is down? If your internet service is down, your VoIP provider will normally reroute any calls to a backup number you’ve set. This is most often a cell phone or landline. But you could also use a backup internet connection with another internet service provider. Written by: Kale Haverford Kale has over five years of experience writing on a broad range of business-related topics, including business technology, software, automation, human resources, employee engagement, and finance. He also holds a BSc in Sociology with a Minor in E-commerce and a certificate in Business Administration. Kale's easy-to-digest, research-driven articles stem from his passion for sharing knowledge with readers, and his bylined work has been published on Yahoo, BestMoney and a selection of SaaS sites. Reviewed by: James Macey Senior Business Software Researcher James thinks all businesses can improve if they use the right technology. At Expert Market, he utilises his 4+ years experience as a researcher to offer specialised advice on a wide range of categories from CRM to Fleet Management.