When it comes to figuring out how many IP cameras can work on your network, there are many factors that need to be considered. The most important is your available Bandwidth. In this article we will take you through each determining factor that will ultimately determine the number of cameras your network can handle. If you are interested in learning the why’s and how’s then read on. If you just want the calculator then jump right to our Calculator section at the end of this article to get your answer. ,
Network Bandwidth
So what is Bandwidth? Basically its the amount of data that can be sent over your network in a measured amount of time. To help explain let’s use pipes and water as an analogy.
Picture two different water pipes that are feeding a large bucket. The larger water pipe will allow much more water to flow through in a given amount of time. The smaller pipe will pass much less water in the same time period. In a network the water would be data and the pipes would be your network. So the more bandwidth your network has the more devices like IP cameras it can handle.
The amount of network bandwidth you have for your cameras will depend on your router, whether you are using Wi-Fi or hardwired network cables, type of camera equipment, configurations and what other devices are using your network. Wow you say. How do I ever figure this out. Well just read on and we help make sense of it.
One point we need to clarify is that your available network bandwidth is not the same as what was given to you by your Internet Service Provider (ISP). The speed of your Internet connection has no bearing on your internal network bandwidth/speed. It will come into play if you plan on viewing or storing video outside of your network. We will touch on that later in this article.
Before we get started I just want to cover the way we measure bandwidth so that we are all on the same page. Mbps stands for Megabits (1,000,000) bits per second. Notice the lowercase “b” as this is important. A lower case “b” refers to Bits while an uppercase “B” refers to Bytes (a group of 8 bits). So MBps is not the same as Mbps. Also we will be using Gbps in some cases which is Giga (1,000,000,000) bits per second. In this article we will be using Mbps or Gbps to describe bandwidth.
Routers and Switches
These days the consumer routers and switches are one in the same. In other words the switch is built into your router. If you have multiple port connections on your router than you can safely say that you also have a network switch.
So how do you figure out your specific bandwidth availability? You can start by checking the specifications of your router as this would be one of the main determining factors. Here are some items that will help determine your network bandwidth.
Wi-Fi 2.4GHz or 5GHz or the new Wi-Fi6
There are many different types of routers out there. Older routers are typically single-band that only handle the 2.4GHz signals (frequency). More modern routers are know as Dual-Band and can handle both 2.4GHz and 5Ghz. So why do I care? Well firstly, a 2.4GHz router has a limited bandwidth of approx. 600 Mbps (in ideal conditions) as compared to 1300 Mbps with 5GHz router. So if you have a single band 2.4GHz router then right of the bat you have a total bandwidth limit of only 600 Mbps (if using Wi-Fi for your cameras).
Another point to consider is that 2.5GHz is known to be more vulnerable to external interference which may also affect your IP Cameras connections. It’s a pretty crowded band. There are a lot of devices that use 2.4G such cordless phones, baby monitors, Bluetooth devices and even microwave ovens. On the over hand, 2.4G has a longer range (passes through walls better) than 5G so cameras could work at a greater distance. However, the 5G band is much less congested which means you are more likely to get a more stable connection. In most cases the 5Ghz band would be better for your IP cameras.
Now one more item that could affect your bandwidth are the 802 standards. Routers conform to specific standards and some standards provide better speeds. Therefore depending which standards your router supports will also determine its bandwidth. I hear ya…does it ever end? Don’t worry, we try to take out all this complexity with our easy to use calculator at the end of this article so don’t bail on us yet. Keep in mind that the cameras used also need to support the 802 standard(s) used by your router.
Now the latest and greatest Wi-Fi6 standard provides much faster speeds and higher bandwidth. It’s a game changer when it comes to bandwidth and overall capacity.
If you are still using a single-band 2.4GHz router then it might be time to look at upgrading to a 2.4G/5G dual-band router or even better a router that supports the new Wi-Fi 6/802.11ax standard.
IEEE Standards and their expected speeds
If you are the curious type the following chart provides some data on the 802 standards
| Name | IEEE Standard | Release Date | Band/Freqeuncy (GHz) | Expected Speed | MIMO | Coverage/Range |
| N/A | 802.11 | 1997 | 2.4 | 2 Mbps | Indoors: 20 m Outdoors: 100 m |
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| Wi-Fi 1 | 802.11a | 1999 | 5 | 54 Mbps | Indoors: 35 m Outdoors: 120/5000 m |
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| Wi-Fi 2 | 802.11b | 1999 | 2.4 | 11 Mbps | Indoors: 35 m Outdoors: 120 m |
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| Wi-Fi 3 | 802.11g | 2003 | 2.4 | 54 Mbps | Indoors: 38 m Outdoors: 140 m |
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| Wi-Fi 4 | 802.11n | 2009 | 2.4/5 | 300 Mbps | MIMO | Indoors: 70 m Outdoors: 250 m |
| Wi-Fi 5 | 802.11ac | 2013 | 2.4/5 | 866Mbps | MU-MIMO | Indoors: 35 m |
| Wi-Fi 6 | 802.11ax | 2019 | 2.4/5 GHz | 450 Mbps/10.53 Gbps | MU-MIMO | TBD |
Wi-Fi or Ethernet
The way in which you are planning to connect your network IP cameras will also affect your available bandwidth. As we mention in the previous section Wi-Fi bandwidth is limited by the router’s radio capabilities (router hardware and 802 standards). However, using hardwired Ethernet cable connections (network cables from your camera directly to your router/switch) will provide better overall performance as the speed/bandwidth for network cabling is much higher than Wi-Fi. Also, let’s consider that the Wi-Fi bandwidth that we listed above in the 802 standards is for all cameras connected to that same router. It is shared between all of the cameras. With Ethernet cables cameras are not sharing their connection to the router/switch. With the right Ethernet cables and router you can theoretically reach up to 10Gbs.
Connecting your cameras with Ethernet cables is certainly a better method for connecting your cameras but it comes with some additional difficulties. Most home/small business owners don’t have the skill nor the ambition to run cables throughout the home/business. Fishing walls, crawling in attics, crawling in crawl spaces, making holes, etc. are just not the things most want to do. However, for those with the skills and drive it would certainly pay off in the end if all your cameras were connected by network cables. Don’t get me wrong, if you have a good Wi-Fi network, the correct amount of cameras properly configured then Wi-Fi will work just fine.
Cameras
There are many different camera types and configurations which can have a huge effect on bandwidth usage and thereby the number of IP cameras you could support on your network. We will go through how different cameras and their configuration can effect your bandwidth.
Resolution
Resolution is referring to the number of pixels being captured by the camera’s image sensor. The data from these image sensors are then compressed and streamed (transmitted) over the network. So a 2 Megapixel (MP) camera would send half the amount of data of a 4MP which in turn will send half of a 8MP camera. As you can see that higher resolution cameras would eat up your bandwidth quickly if you had a lot of them.
| Typical IP Camera Bandwidth | ||
| Resolution | H.264 | MJPEG |
| 1MP (1280*720) | 2 Mbps per camera | 6 Mbps per camera |
| 2MP (1920*1080) | 4 Mbps per camera | 12 Mbps per camera |
| 4MP (2560*1440) | 8 Mbps per camera | 24 Mbps per camera |
Frames per Second (FPS)
Cameras can be configured at different frame rates which will effect your bandwidth usage. For example, a camera set to 1 FPS would be capturing 1 image (frame) per second. This image would then be compressed and sent over the network using a certain amount of bandwidth. Now if we were to set the same camera to 10 FPS with all other factors remaining the same we would see a increase in our overall bandwidth requirements. You may think that since we increased our frame rate by a factor of 10 that our bandwidth would also increased by a factor of 10. Well this wouldn’t be the case as frame rates do not have a linear affect on bandwidth. This is due to compression codecs like H.264/5 and how they work. Suffice to say that you will realize a bandwidth increase in our example but it may be somewhere between 3-4x not 10x as expected.
Setting the correct frame rate is important and the frame rate you choose will depend on your particular needs for the given camera. A typical rate used in the industry is 15 FPS which provides the best compromise between details being captured and bandwidth used.
Video Compression
Video data from IP security cameras is always compressed before sending over a network. The most common compression standard used in the security industry today is H.264. Depending on which video compression codec (encoder/decoder) is used by your camera it will have an effect on the overall bandwidth usage on your network. However, most security cameras today support and default to the H.264 standard.
The newer H.265 codec is also available and has higher compression rates. It could improve your compression by up to 50%. However, it isn’t as widely adopted yet and may have a higher chance on incompatibility with some hardware.
Standards such as MJPEG is also available in many cameras. This standard provides high quality video and uses less processing power that H.264/5 but uses much more bandwidth and storage space. So if you have a choice we would recommend using H.264/5
How you use your cameras will affect your Bandwidth usage.
The way in which you plan to use your cameras will also affect your bandwidth.
Viewing
If you are not storing video somewhere on the network (see next section) and nobody is viewing any of your cameras then your cameras will be using almost no bandwidth at all. They would be only sending very small amounts of data just for housekeeping reasons. Its only when you request to view any video that your camera(s) will start sending their video data and using your available bandwidth.
Storage
Video storage is the process of retrieving video from your IP cameras and placing it on a storage media device for later viewing. In a home or small business environment this is typically done by storing locally in the camera on a SD card or on a Network Video Recorder (NVR).
Storing locally on a SD card means that the video will not be sent over the network, thereby reducing bandwidth usage, but is stored locally on a small SD memory card inserted into the camera. This comes with some great benefits but also some drawbacks like limited storage capacity. Not all cameras have the local storage feature but many do.
Storing video on a Network Video Recorder (NVR) has its own pros and cons but the main drawback is that may use your network bandwidth continuously. So depending on the frame rates, compression, resolution and other configuration options are set on your cameras there could be large bandwidth usage. This would be compounded if you have multiple cameras on the network.
Of course you also have the option of not recoding video at all and relying on features like video motion detection to have video clips sent to your phone.
| Feature | Local SD Card | NVR |
|---|---|---|
| Bandwidth Usage | Low | med-high |
| Storage Capacity | Low - typically 128G max | High |
| User Experience | Med | High |
| Cost | Low | High |
Video Storage
Camera resolution is probably the biggest factor on bandwidth usage. Resolution is referring to the number of pixels being captured by the camera’s image sensor. The data from these image sensors are then compressed and streamed (transmitted) over the network. So a 2MP camera would roughly send half the amount of data of a 4MP which in turn will send half of a 8MP camera. As you can see that higher resolution cameras would eat up your bandwidth quickly if you had a lot of them.
Summary
So now that we have covered the main factors that affect your bandwidth usage we can start planning or camera system to both meet our needs but keeping within our bandwidth availability.
Bandwidth Calculator
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Author: Phil Ciraolo
I have been in the security industry for over 44 years. During this time I held many positions including installer, service technician and design engineering. Systems worked with include intrusion systems, video surveillance, card access, intercoms and many others. Installations ranged from small residential to large integrated systems. I have walked across overhead cranes, crawled in under floor dirt crawl spaces, hung from 50 foot bucket truck in -10 degree temperatures all with the sole purpose to install security systems. To help with todays App crazy world I also have formal training in software programming and app development. I hope that with my experience I will be able to help you with anything security and home automation related.
very informative post