Quote:
I'll buy the book, this is the first time I've worked with a network, definitely not my strong point.
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I was joking about the book. My copy would be over thirty years old, dog-eared , no idea where it lies and vastly out of date as it was written before Mobile Internet, Personal Hotspots, WiFi, home network routers, DHCP, VPN, IPSEC & IP v6 were even invented.
All you really need to know is the
concept of a "private" network. Your GL..iNet slate router,
iPhone Personal Hotspot, Yacht Devices YDNR-03 WiFi Gateway and your home WiFi router all use/issue private IP subnet addresses 192.168.n.
For example a subnet 192.168.1.
In general for 192.168.n subnets, the subnet mask is 255.255.255.0.
Each 192.168.n subnet supports 255 host addresses, eg. 192.168.1.32 is a valid IP address in the 192.168.1 subnet.
Note the IP address 192.16.1.255 is the broadcast address, anything sent to this address will be sent to all devices on the 192.168.1 subnet.
The Personal Hotspot,WiFi Router usually assigns itself the address 192.168.n.1. This is known as the default gateway address and any request to an IP address outside the subnet's range will be directed to the gateway and if a
route exists, further transmitted.
So continuing on with this example your GL..iNet router may assign itself the address 192.168.1.1.
That's why you can access the WiFi router's admin page by using a web browser connecting to
https://192.168.1.1
The client uses the subnet mask to determine if an IP address is on its own subnet or on an external network
So for a subnet of 192.168.1 it means that a request to a device with an IP address of 192.168.1.53 will be found in the local subnet and will not be routed externally. A request to another address such as 104.26.0.68 (cruisersforum.com) will be forwarded to the default gateway address and forwarded externally should a
route exist.
To ease the burden of configuring static IP addresses, subnet mask and default gateway addresses for each client device, WiFi routers, Personal Hotspots dynamically assign IP addresses and configure the subnet mask and default gateway address to clients using a protocol known as Dynamic Host Configuration Protocol (DHCP).
Just like postal addresses you don't want to have two devices with the same IP address, so dynamic addresses help eliminate this risk.
So in this example your GL..iNet router will assign addresses in the range 192.168.1.2 - 192.168.1.254 unless you have explicitly excluded some addresses or limited the range of dynamic addresses and assigned a static IP address to a client device. It will also configure 255.255.255.0 as the subnet mask and 192.168.1.1 as the default gateway address.
If you were to assign a device a static IP address it needs to be in the same subnet, eg 192.168.1.101 and have the correct subnet mask and default gateway address.
Long and windy but hopefully helpful.