I was kinda missing the last puzzle piece on the explanation of subnet masks, so I'll put it here for anyone else with the same question. Basically, the subnet mask masks the networking part of the IP address (first three octets = networking part; last octet = host part). If the first three octets (sets of three numbers), are the same for every device in the subnet, they don't matter, just like I don't have to say that I'm from Town A in a meeting that's only for citizens of Town A. The second job of the subnet mask is to define which devices can talk to each other by defining what parts of their IP address have to match. The network that we call the Internet consists of so many devices that it would just be too messy if they all tried to just talk to each other, which is why we have subnets that define who can talk to whom. There are Class A (first octet has to match [255.0.0.0]), Class B (first two octets have to match [255.255.0.0]) and Class C (first three octets have to match [255.255.255.0]) subnets/networks, just like the world is divided into the organizational units of countries, states and communities. Although your lighting network is likely not going to be connected to the internet, the organizational units are the same. As implied above, if an octet has to match, the number for that octet in the subnet mask is 255. If an octet doesn't matter, the number is 0. This way, the subnet mask also defines how many IP adresses can be in its subnet. The reason why "octet has to match"=255 and why "octet doesn't matter"=0 is that these numbers define how many different types of that octet can exist in the subnet, but it works differently than one might assume at first. Basically, it's 256 - "number in subnet mask" = "number of different numbers for that position". So if your subnet mask says 255 for the first octet, that means there is 256-255=1 variant of first octet that can exist there. Let's say that currently, all your devices have an IP adress whose first octet is 187. Then you have a device with an IP adress that starts with 188, but the subnet mask won't allow it to talk to the others because 188 is another variant of the first octet from 187, but there can only be one variant, so naturally, all the devices in the subnet have to have the same first octet. So if the last octet in the subnet mask is 0, there are 256-0=256 different adresses available in your subnet. This is the maximum for a Class C subnet, so you'll need a Class B subnet if you have more devices than that.
It's more complex than this. Often you will see a mask ending in 255, but it might be much smaller. CIDR blocks are far more common these days (alluded to in the video with the ending of .255 and 'more complex networks' - they are much more common than alluded to here!) and you might see a network expressed in those terms. If you use the assumption of an old 'class C' network you might stomp over lots of other stuff. Unlikely in a local DMX setup, but if you are sharing the network with other stuff, it might be important.
They do not necessarily always work in the sense of Device A has an IP of:192.168.0.100 and Device B has an IP of: 192.168.1.200- needs to have a subnet mask of "255.255.0.0" in order to talk and be failsafe all of the time. The zero in the usual class C subnet mask of 255.255.255.0 just lets you know that the final octet are the bits relative to the number of possible hosts, and the 255 are the bits relative to the network. This school of thought can work until it doesn't.
Yes, as I mention often when I cover networking, this is simple, entry-level information in the video, What you're doing is taking it to another level, which isn't for everyone.
In this case you should use a router to bridge the two networks. If you are running two separate subnets you are doing it for good reasons (perhaps broadcast traffic, perhaps to control what that network of devices can do to your wider network). If your network is limited to lighting then go ahead, but if you are part of a wider network with sound, lighting, and even internet then think twice; you might destroy some other part of the show. This is especially important if you are told to use a smaller subnet (ie something is less than 255).
I was kinda missing the last puzzle piece on the explanation of subnet masks, so I'll put it here for anyone else with the same question.
Basically, the subnet mask masks the networking part of the IP address (first three octets = networking part; last octet = host part). If the first three octets (sets of three numbers), are the same for every device in the subnet, they don't matter, just like I don't have to say that I'm from Town A in a meeting that's only for citizens of Town A.
The second job of the subnet mask is to define which devices can talk to each other by defining what parts of their IP address have to match. The network that we call the Internet consists of so many devices that it would just be too messy if they all tried to just talk to each other, which is why we have subnets that define who can talk to whom. There are Class A (first octet has to match [255.0.0.0]), Class B (first two octets have to match [255.255.0.0]) and Class C (first three octets have to match [255.255.255.0]) subnets/networks, just like the world is divided into the organizational units of countries, states and communities. Although your lighting network is likely not going to be connected to the internet, the organizational units are the same. As implied above, if an octet has to match, the number for that octet in the subnet mask is 255. If an octet doesn't matter, the number is 0. This way, the subnet mask also defines how many IP adresses can be in its subnet.
The reason why "octet has to match"=255 and why "octet doesn't matter"=0 is that these numbers define how many different types of that octet can exist in the subnet, but it works differently than one might assume at first. Basically, it's 256 - "number in subnet mask" = "number of different numbers for that position". So if your subnet mask says 255 for the first octet, that means there is 256-255=1 variant of first octet that can exist there. Let's say that currently, all your devices have an IP adress whose first octet is 187. Then you have a device with an IP adress that starts with 188, but the subnet mask won't allow it to talk to the others because 188 is another variant of the first octet from 187, but there can only be one variant, so naturally, all the devices in the subnet have to have the same first octet. So if the last octet in the subnet mask is 0, there are 256-0=256 different adresses available in your subnet. This is the maximum for a Class C subnet, so you'll need a Class B subnet if you have more devices than that.
It's more complex than this. Often you will see a mask ending in 255, but it might be much smaller. CIDR blocks are far more common these days (alluded to in the video with the ending of .255 and 'more complex networks' - they are much more common than alluded to here!) and you might see a network expressed in those terms. If you use the assumption of an old 'class C' network you might stomp over lots of other stuff. Unlikely in a local DMX setup, but if you are sharing the network with other stuff, it might be important.
Where are the two links you mention starting at 10:52 on networking elsewhere on youtube? I do not see them in your description?
Arghh! Here you go:
ua-cam.com/play/PLrXNpNQ0Imr5plps5bSD2mgUjZtTMF8d5.html
and
www.elationlighting.com/e3-training-videos (the ones on networking)
They do not necessarily always work in the sense of Device A has an IP of:192.168.0.100 and Device B has an IP of: 192.168.1.200- needs to have a subnet mask of "255.255.0.0" in order to talk and be failsafe all of the time. The zero in the usual class C subnet mask of 255.255.255.0 just lets you know that the final octet are the bits relative to the number of possible hosts, and the 255 are the bits relative to the network.
This school of thought can work until it doesn't.
Yes, as I mention often when I cover networking, this is simple, entry-level information in the video, What you're doing is taking it to another level, which isn't for everyone.
In this case you should use a router to bridge the two networks. If you are running two separate subnets you are doing it for good reasons (perhaps broadcast traffic, perhaps to control what that network of devices can do to your wider network). If your network is limited to lighting then go ahead, but if you are part of a wider network with sound, lighting, and even internet then think twice; you might destroy some other part of the show. This is especially important if you are told to use a smaller subnet (ie something is less than 255).
nice!
Thank you! Cheers!