What Does "Network" Mean?
A "Network" is a group of devices linked by blocks that can pass channels, like cables or fullblock machines and devices. (Charger, ME Interface, ME Drive, etc.) Technically a single cable is a network, actually.
An Aside On Device Positioning
For devices which have some specific network function (like an ME Interface pushing to and pulling from network storage, a ME Level Emitter reading the contents of network storage, an ME Drive being network storage, etc.) the physical position of the device does not matter.
Again, the physical position of the device does not matter. All that matters is that the device is connected to the network (and of course which network it's connected to).
An easy way of determining what's connected in a network is using a Network Tool. It will show every component on the network, so if you see stuff you shouldn't or don't see stuff you should, you have a problem.
For example, this is 2 separate networks.
This is also just 1 network, as cable color has nothing to do with network connections other than cables of different colors not connecting to each other. All colors connect to fluix (or "uncolored") cables.
Less Intuitive Connections
In this case, this is just 1 network, because the ME Pattern Provider, being a fullblock device, acts like a cable, and the Inscriber does similar. Thus, the network connection passes through the provider and inscriber.
To prevent this (useful for many autocrafting setups involving subnetworks), you can right-click the provider with a Certus Quartz Wrench to make it directional, in which case it will not pass channels through one side.