What is the Bandwidth Required for VoIP?

Here at Carolina Digital Phone, one of the most important (and common) questions we get asked from prospective customers is: what is the bandwidth required for VoIP? Other common questions asked are about download speed and overall internet speed. In a moment, we dive into these questions. First, let’s take a step back and look at some bandwidth basics.  

What is Bandwidth, Anyway?

The term bandwidth is used all over the place. But just what does it actually mean in simple terms? Essentially, bandwidth is a measurement of the maximum capacity of a communication link (wired or wireless) over a network connection in a specific amount of time. Usually, bandwidth is described in bits, kilobits, megabits, or gigabits that can be transmitted per second (data transfer rate, or DTR). As we move on, we talk more about minimum requirements, bandwidth usage, and your internet connection.

Now, by this point, you might be saying to yourself: “Hold on a minute, I’m here to learn what the bandwidth required for VoIP, not for an IT lesson.” Of course, you’re right! But that’s exactly why we need to take a step back. This will all make perfect sense in a few seconds (we promise!), so please keep reading.

Why Bandwidth Matters (Part 1)

The reason that understanding and identifying maximum bandwidth speed is so important, is because the more bandwidth a data connection has, the larger volume of data it can send or receive at the same time. 

Think of a 1/2″ water pipe and a 3/8″ water pipe. Both pipes are made of the same material, and so in terms of quality, they are identical. But the 1/2″ water pipe can simply transfer more water at a given time because it is larger.

Bandwidth is a technical term that refers to the rate of data transfer over an internet connection within a specific time frame. To ensure efficient usage, a portion of the bandwidth provided by the ISP needs to be allocated.

A stable internet connection is crucial for the optimal performance of VoIP phone calls, which rely on internet connectivity. Intensive internet usage or concurrent application use can decrease available bandwidth for cloud phone systems, leading to slower speeds and inferior call quality. A fast download speed is critical to good Voice over Internet Protocol or VoIP service.

Why Bandwidth Matters (Part 2)

Ideally, there would be enough bandwidth available to speedily transmit data back and forth. But just as there are traffic jams on freeways, there are bandwidth jams on networks.

We often experience this on home networks, when multiple people carry out — or make, that try to carry out! — bandwidth-intensive tasks at the same time (e.g., streaming TV, gaming, listening to music, etc.).

Your Internet Service Provider (ISP) and whichever plan you select will define the speed of your Internet connection. Recommended bandwidth requirements may vary depending on the processing technology, and the most accurate speed recommendations will come from the Internet providers. It is worth your time to shop around and compare Internet Service Providers.

What is the Bandwidth Required for VoIP? Right & Wrong Answers

Now that we have covered the fundamentals, we can tackle the question that started us off: what is the bandwidth required for VoIP? There are two answers, one incorrect and the other correct. Let’s start with the former.

Cloud-based phone calls that use the standard protocol G711 require approximately 64kbps per phone call. Technically, this is true. But practically, it is wrong, because 64kpbs is the bare minimum. So yes, it’s possible to make and receive calls with this minimal bandwidth, but it’s definitely not recommended. 

Now, for the right answer: based on our 23+ years of experience, we strongly recommend increasing the bandwidth to at least 100kbps upload and download per line. So, that means if there are 5 lines, then the minimum bandwidth should be 500kbps. Knowing the number of concurrent calls you will have is important.

Keep in mind that “100kpbs per line” is not a rule or standard, but a general guideline. If your business is going to regularly engage in higher-bandwidth activities like video conferencing, or if there are usually going to be other significant demands on the network (e.g., transferring large files, accessing a database, etc.), then you will need more bandwidth. This will ensure suitable calling quality, and overall system speed and performance. It will also create a “buffer zone” for multiple people to use the network at the same time, but without running into any traffic jams.

Other Factors to Consider

Your choice of router and wiring also play a huge role in VoIP (and overall network) performance. We recommend the following:

  • Using a gigabit connection on switches and routers.
  • Having Quality of Service (QoS), Virtual Local Area Network (VLAN), and bandwidth allocation options in your router.
  • Using at least CAT 5e cabling to provide a solid network infrastructure. This helps ensure the highest quality possible

Assessing Your Needs

So, by this point, you are likely asking EXACTLY — not generally or usually or typically — but PRECISELY what is the bandwidth required for VoIP in your business? Is the correct answer 100kpbs per line? 200kpbs? 1mbs? 

Well, we would love to give you a black-and-white answer, but we cannot. Truly, it depends on what you will be doing, and what you anticipate doing in the months or years to come.

But don’t worry! When you choose Carolina Digital Phone as your VoIP Solution Provider, you do not need to do any analysis, because we take care of that for you. Our team of experts will perform an in-depth assessment of your needs and infrastructure. 

From there, we will determine if your current bandwidth is suitable. If not, then we will provide you with targeted, cost-effective recommendations to accommodate the expected number of concurrent calls you will need to handle.

For example, you may find that simply rescheduling certain bandwidth-intensive ongoing operational activities to business downtimes (e.g., evenings and weekends) could significantly improve day-to-day bandwidth. Or, you may find that some employees are routinely accessing bandwidth-hogging sites like Spotify. 

Of course, there are other strategies and methods as well, including those that require hardware upgrades. For example, CAT5 cabling only supports up to 100mbps, while CAT 5e cabling supports up to 1000mbps. This means that even if your current bandwidth is rated for 200mbps, you will only experience (at most) 100mbps! Naturally, replacing your CAT5 cabling with CAT 5e cabling — which is very inexpensive — will dramatically increase bandwidth and performance. 

The Final Word

At Carolina Digital Phone we will determine the bandwidth required for VoIP, and ensure that our system meets your high expectations for quality, performance, and reliability. Remember, we are a PARTNER and not just a VENDOR. We will be supporting your satisfaction and success every step of the way, and for years and decades to come!  

Learn more by contacting us today. Call (336) 544-4000.