How do I check my WAN IP

What's my IP address?

The special thing about Macs is that things work simply, beautifully, and unobtrusively. You don't really need to know a lot about macOS, computer architecture, file systems, application interfaces, or protocols. You just use your programs and you are creative. This also applies to Merlin Project, Merlin Project Express and Merlin Server.

You can publish project structures from Merlin Project in the calendar and these are synchronized between different devices. Contacts can be used as resources and chosen for assignments. Or you can get Merlin Project to send reports to those involved in the project, share your project on a Merlin Server and smoothly synchronize changes made by other users in a file. It all just works!

Occasionally, however, you may find it beneficial to have a little technical understanding.

For example, if you have a Merlin server on a Mac in your LAN (Local Area Network) and need to access it from a portable device (macOS or iOS) over the Internet, you need to know which WANIP Address the services can be reached.

What is an IP address?

Computers within a computer network require an identifier with which they can be clearly identified. The license plate helps Calculator A, Calculator B to find and ask for or send data.
In Internet communication, this indicator is called Internet protocol address (IP address in short).
There are different versions of IP addresses. The most common Internet protocol version 4 (IPv4) is used, with the use of the newer version IPv6 - which addresses the long-awaited problem of IPv4 address exhaustion - increasing steadily.

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

You can find more information in Wikipedia.

Where can I find my IP address?

  • On a Mac, open "System Preferences ...".
  • Click on "Network".
  • Select the highest listed service on the left side of the dialog that tells you that you are connected. If you are connected via the WLAN, it is called "WLAN". If you are connected by a cable, it will show up as "Ethernet".
  • Your IP address is displayed on the right side of the dialog.

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 cannot be routed over the Internet. A Calculator A with a private IP address of cannot Calculator B with a private IP address of You must use public or wide area network (WAN) IPs.

What is a public or WAN IP?

That's easy. A public or WAN IP (Wide Area Network) is an IP address that can be routed over the Internet. In IPv4 it starts with any number except 192, 10, 172, 1 or 255.

This or any other website that you access via your web browser, or even your mail server, has a public IP that you do not really see when you call it up, because you prefer to call up host names for the sake of clarity.

Your router - the device that connects your LAN to the Internet - also has a WAN IP address.

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

Routers connect you to the Internet and protect your LAN at the same time

Routers are designed to block unwanted incoming connections. You assign unique LAN IP addresses to your local devices using DHCP. You - as the administrator of your router - can open individual ports and, if necessary, allow port forwarding from / to specific private addresses.

What's my WAN IP?

Access to documents on the Merlin Server from a mobile device (macOS or iOS) via the Internet

Now that you know which WAN IP you can use to access the Merlin Server services, configure your access as described in the accompanying quick guide.

NOTE: In order for the connection to work, the administrator of the remote LAN must activate port forwarding for the Merlin Server services (which should be available over the WAN).