What IP Address Should I Use for Network Devices?
How can I access a local device from outside the local network?
Internet Protocol (IP) addresses are in the form ###.###.###.### where ### is a decimal number in the range 0-255. Private networks are designated three address ranges (subnet mask): 10.0.0.0 - 10.255.255.255 (255.0.0.0) 172.16.0.0 - 172.31.255.255 (255.240.0.0) 192.168.0.0 - 192.168.255.255 (255.255.0.0) Since most homes have fewer than 256 internet connected devices, it is common to use 192.168.10.### (255.255.255.0) for inside IP addresses. In this case, 10 is a number unique among all the networks we need to connect to via Virtual Private Network (VPN). If you do not need to connect to other networks with VPN, use 192.168.1.### as this is a common default range for devices. Many choose to make the Router IP a high number that is outside the DHCP range, like: 192.168.10.254 Dynamic Host Configuration Protocol (DHCP) is a function the router performs to automatically pass out IP addresses to devices on the network. This address is subject to change each time the device connects to the network. So, if you have a device like a camera that you want to bookmark and be sure it will always have the same IP address, set up the device with a static IP address and configure the Router DHCP Starting IP Address to reserve a number of addresses at the beginning of your range, like 50. That will reserve the first 50 IP addresses in your range for static IP devices. The Maximum Number of DHCP Users: 50 setting designates that only 50 IP addresses will be issued allowing you to use high IP addresses (like 192.168.10.254) for Routers, Switches, and Wireless Access Points (WAP). While you can use any addresses outside the DHCP range you wish for static IP addresses, this approach simplifies things in this way. You can assume your Routers, Switches, and WAPs are addressed 192.168.10.254, 192.168.10.253, 192.168.10.252 ..., and you can assume your devices on the network are addressed 192.168.10.1, 192.168.10.2, 192.168.10.3 ... Nevertheless, writing down the static IP addresses you assign to your devices will save you a lot of time and frustration when you need to access them.
All internet connected devices must have a unique IP address. This address is a number represented by 4 decimal numbers separated by a "dot" (or period). Like ###.###.###.###. Each of the 4 numbers is in the range 0-255. We can access addresses by names indirectly through the Domain Name System (DNS). This is a service provided by a large number of servers that returns the IP address associated with a name. If you want to access servers or devices on your local network by name, you must have a local server that provides DNS service for your local network. If you don't have a server that can provide DNS, you can edit the hosts file (%windir%System32\drivers\etc\hosts) on each workstation. Dynamic Host Configuration Protocol (DHCP) is an internet service that provides IP addresses to devices to avoid conflicting addresses. Servers and devices that need to be accessed by workstations need to have the same IP address and are normally assigned a static IP address. The DHCP server you use, which is typically on your local router, needs to be configured to exclude a range of addresses used as static addresses. Most Internet Service Providers (ISP) use DHCP to dynamically assign an IP address for your local network and charge an extra monthly fee for each static address. Internet services like noip may be used to access a your local network even if the address changes using Dynamic DNS (DDNS or DynDNS), a method of automatically updating a name server in the Domain Name System in real time. Most ISP's change your local network IP address very infrequently. To determine your local network's IP address, use whatsmyip.net or just type whatsmyip in Google. Once you have your outside IP address, you can access your local network from anywhere on the internet. The address is the address of your router, which may be a computer, or a router device with limited functionality. If you have a server and the server is running web server software (like Apache or Microsoft Internet Information Server (IIS)), the outside address will return the home page of the web server. If you have a router device, the address will connect to the device. To access another device (that is not your router) on your local network, like a camera, you can use port forwarding. A IP port number is used along with the IP address to determine where to route network traffic. There are certain ports reserved as the default port for specific uses. Hypertext Transfer Protocol (HTTP) for example uses port 80 by default for web server traffic, HTTPS port 443, File Transfer Protocol (FTP) port 20, Internet Message Access Protocol (IMAP) port 143, (see Wikipedia: List of TCP and UDP port numbers for many others. In a browser, a port may be designated by ###.###.###.###:ppp where ppp is the port number. For example, https://www.google.com:443 may be used to access Google. The :443 is not necessary only because 443 is the default port for https. Most router devices may be configured to do port forwarding. In the router configuration, this feature may be called Applications & Gaming. Select a unique port (not a reserved as a default port) and map the port to a local IP address. When you add this port number to the end of the outside address of your router, the router forwards the traffic to the associated local IP address. The device itself may need to be configured to use the same port number.