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VirtualPBX What You Need to Know: What is SIP Calling?

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VirtualPBX What You Need to Know: What is SIP Calling?

What is SIP CallingWhat is SIP calling? Let’s break down that acronym and discuss how the process of making phone calls through the internet works.

SIP stands for Session Initiation Protocol and refers to voice calls transmitted over a SIP Trunk or SIP Channel. The concept of SIP Trunking is addressed in more depth in our SIP Trunking FAQ’s page, and we’ll explain it further in the sections included in this article.

You should enter this discussion with the knowledge that VoIP (Voice Over Internet Protocol) calls are not the same as SIP calls. They use similar technology — harnessing the internet protocol (IP) to operate — but they were created to address separate needs. The SIP protocol can handle voice, video, instant messaging, and other data; so can VoIP. And like many of the topics we’ve discussed in previous What You Need to Know Blogs about various telecommunications issues, SIP Trunking is one of those things that may seem daunting at first but is actually pretty clear once you have a broader understanding of the issue.

So Really, What is SIP Calling?

SIP Calls are voice conversations that use a specific route to connect parties. First, let’s address how telephone calls were traditionally made. The two basic components of a traditional business telephone system include accessing the PSTN (Public Switched Telephone Network) and managing the calls and their routing/voicemail/etc. over a PBX (Private Branch Exchange). This already would indicate that SIP calling is something that is traditionally reserved for similar situations, specifically in that it’s more for businesses only. Spoiler alert: that is mostly the case. Some consumer SIP calling capabilities exist on open source platforms like the Android mobile phone operating system, but for the vast majority of SIP Trunk clients and customers, SIP calling is primarily for businesses. Moving on, a business with an on-site PBX used to connect to the PSTN exclusively over copper wires connected by the legacy telephone carriers, but in the advent of the digital and internet ages, that system changed dramatically.

SIP Calling Wasn’t the First Option

To begin handling the increased connections and complexity that initially came with having both landlines and internet connections running through the same on-site PBX hardware that was designed for voice only, PRI lines were created. PRI (Primary Rate Interface) Lines were an early solution to begin managing these new connections and have since been outdated by the more capable SIP Trunking option. We go into great detail on the SIP Trunking vs PRI in another post, but it boils down to SIP Trunking being faster to implement, more capable of handling the needs of voice-only data traffic, and an overall reduction in operating and installation costs. SIP calling via a SIP Trunk accomplishes all of this by eliminating the need to have a traditional, physical connection to a legacy phone company. This simplifies things on the site of the PBX by also eliminating the need for multiple phone lines because SIP Trunks leverage some of the flexibility that comes from cloud-based communications and can expand and contract to accommodate the needs of any business as its call activity spikes.

Just One Facet of Cloud Communications

What is SIP calling is just one of those questions that arises now that telecommunications have more than one route (specifically, a single copper wire) to connect people across a vast array of distances and devices. As we mentioned earlier, though, SIP connections can transmit a variety of data beyond just voice connections and that makes it more inherently “cloud” than anything else. By this we mean the majority of the benefits of cloud-based communications come from the infinite number of customizations and modifications that can be made for free to advanced telephone systems with a press of a button versus for a fee with the eventual visit by a telephone company engineer. This also means that SIP Calls are operated over connections that are optimized for the prioritization of voice over data, meaning that if traffic is at a peak the voice connections remain crystal clear and upload/download speeds of your favorite cat video may be constricted until the surge is over. Also, and possibly most importantly in light of the pace of business in the modern era, speed of implementation of SIP Trunking, like all cloud communications, is lightning fast in comparison to PRI lines. What traditionally takes PRI lines upwards of 45 business days to accomplish can be done with a SIP Trunk in as little as a 15 minutes or less.

With all of this under consideration, the next time someone asks what is SIP calling, perhaps the best answer is to simply say, “A really good idea.” If that’s the case, feel free to learn more about SIP Trunking for business and our other hosted VoIP business phone plans by reading more. Also, remember to let us know of other topics you’d like to learn more about in future What You Need to Know blogs by sending us suggestions over Facebook or Twitter.

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