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IP addresses can be categorized as private and public addresses. Private IP addresses cannot be reached via the Internet, whereas public IP addresses can. For instance, most home networks have a router. This router will have a public IP address that is accessible through the Internet. An Internet Protocol address (IP address) is a numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication. An IP address serves two main functions: host or network interface identification and location addressing.

Computer EngineeringComputer NetworkMCA

Private IP Address and Public IP Address are used to uniquely identify a machine on the internet. Private IP address is used with a local network and public IP address is used outside the network. Public IP address is provided by ISP, Internet Service Provider.

Following are the important differences between Private IP Address and Public IP Address.

Sr. No.KeyPrivate IP AddressPublic IP Address
1ScopePrivate IP address scope is local to present network.Public IP address scope is global.
2CommunicationPrivate IP Address is used to communicate within the network.Public IP Address is used to communicate outside the network.
3FormatPrivate IP Addresses differ in a uniform manner.Public IP Addresses differ in varying range.
4ProviderLocal Network Operator creates private IP addresses using network operating system.ISP, Internet Service Provider controls the public IP address.
5CostPrivate IP Addresses are free of cost.Public IP Address comes with a cost.
6LocatePrivate IP Address can be located using ipconfig command.Public IP Address needs to be searched on search engine like google.
7RangePrivate IP Address range:Except private IP Addresses, rest IP addresses are public.
8ExamplePrivate IP Address is like IP Address is like

The best thing about macs is that things work simply, nicely and silently. You do not really need to know much about macOS, computer architectures, file systems, application interfaces or protocols. You just use your applications and be creative. This applies to Merlin Project, Merlin Project Express and Merlin Server as well.

You can let Merlin Project for example publish project structures to the Calendar and have them synced among various devices. You see it accessing Contacts for the resources. You can get it to mail reports to project stakeholders, share your project to a Merlin Server, and sync edits of other users into one file seamlessly. It all simply works like a charm!

Occasionally though, a bit of technical understanding comes handy to you.

When you have for example a Merlin Server on a mac in your LAN (local network area) and need to access it from a portable device (macOS or iOS) over the internet. In such a case you need to know by which WANIP address to call it.

What is an IP address?

Computers within a computer network, need a label identifying themselfs uniquely. The label helps computer A to find computer B and ask for data or send any.
In internet communications this label is called Internet Protocol Address (IP Address in short).
There are various versions of IP addresses. The most commonly used is Internet Protocol version 4 (IPv4), while the deployment of the newer version IPv6 - dealing with the long-anticipated problem of IPv4 address exhaustion - is continuously increasing.

IPv4 addresses are defined as a 32-bit number and when displayed in notations look like: 12.345.67.90
IPv6 addresses use 128 bits and when displayed look like: fe80::c01:8348:bd92:cb6

You'll find more information in Wikipedia.

Where to find your IP address?

  • On a mac, open the 'System Preferences…'
  • Click on 'Network'
  • Select the top most listed interface on the left of the dialogue stating you are connected. If you are connected over the Wi-Fi, it will be 'Wi-Fi'. If you are connected over cable, it will read as 'Ethernet'.
  • See your IP address shown on the right side of the dialogue.

This IP address is your private IP address. It starts with 192, 10, or 172.

A private IP address only works within the LAN

Private IP addresses are not routable over the internet. So a computer A with a private IP address of won't be able to locate a computer B having a private IP address of They'll need to use public or WAN (wide area network) IPs.

What is a public or WAN IP?

Examples Of Public Ip Addresses

That's easy. A public or WAN (wide area network) IP is an address which can be routed over the internet. In IPv4, it will start by any number other than 192, 10, 172, 1 or 255.

This, or any other website that you access via your web browser, or even your mail server, have a public IP that you don't really see when you call it, because you prefer to call hostnames for reasons of clarity.

Even your router - the device connecting your LAN to the internet - has a WAN IP adress.

You can see your WAN IP in your router, or use web services.

Is My Ip Private

Public vs private ip addressIs My Ip Public Or Private

Routers connect to the internet while protecting your LAN

Routers are designed to block unwanted incoming connections. Free hide proxy websites. They offer - over DHCP - LAN IP addresses to your local devices. You can however choose to open independent ports and allow forwarding from/to specific private adresses if required.

Which is my WAN IP?

Access documents of Merlin Server from a portable device (macOS or iOS) over the internet

Now that you know by which WAN IP you can access the Merlin Server services, configure your access as explained in the related quick guide.

NOTE: For the connection to work, the admin of that remote LAN needs to enable port forwarding for the Merlin Server services (which are to be available over the WAN).