What is the difference between VoIP and SIP?

This is something we get asked all the time: what is the difference between VoIP and SIP? Unfortunately, this is yet another example of technical jargon complicating an already complicated subject. But it’s an important one to understand if you’re considering whether to make the switch away from your existing ISDN phone system.

In truth, it has two answers, the technically correct one and the more common terminology used by the layman.

So what is VoIP and what is SIP?

VoIP is VOICE OVER INTERNET PROTOCOL, a method of using packets of data over an internet connection to transport your voice, rather than voltage over a copper wire on traditional telephony.

SIP is the actual protocol referred to in the “P” of Voice Over Internet Protocol (VoIP). SIP meaning “Session Initiation Protocol” is the actual stream used to deliver VoIP.

So as you see, in technical terms they are pretty much one and the same thing, VoIP wouldn’t work without SIP and SIP is the P in VoIP…With us so far?

But what about how they are used in more day-to-day terms? If you get presented with the option for a VoIP phone system and then a SIP system what are you actually being offered, what’s the difference and, most importantly, what’s right for your business?

When most people talk about VoIP system, provided at a monthly fee they are most probably talking about a “hosted” phone system. That is, a cloud-based VoIP system for which you pay an ongoing rental. You are effectively renting a slice of a big phone system in the cloud with no hardware (other than the handsets) being installed to your premises. There are lots of considerations if you like the idea of a VoIP phone system, for example, scalability, portability, low start-up costs etc. which we discuss further here.

When most people talk about a “SIP phone system” they are usually talking about an on-premises phone system, like you would have used with ISDN lines but updated to use the internet. Equally there are considerations if you prefer the in-house options, you get more control with an in-house system, better reporting, lower lifetime costs etc. which we discuss further here.

Unlike a lot of IT and Mobile phone companies who have recently jumped into the Hosted VoIP market and only sell hosted VoIP phone systems (its considered a simple sale), we at LG networks have been selling telephone solutions since two cups were joined with string (almost). Nowadays we are one of the few telephone companies you’ll find who are not an I.T. company. We’re specialists in voice, and we supply and install traditional ISDN systems, SIP IP in-house systems and fully hosted VoIP phone systems. We don’t have an agenda to promote the only solution we sell (as some do), because we do them all, and have been for years. And we install them all with our own engineers with years of experience. We are also backed by our own small but dedicated support team, not a faceless call centre.

We discuss all options with you, run through the advantages and disadvantages of all viable solutions, discuss your current needs, your future plans and other factors too like the quality of your internet connection. Usually once we’ve done that the correct option is fairly obvious, if you’re unsure which is best for you, please give us a call.

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