Remote Screen Sharing over the Internet

Internet Public port 5900 to Mac A port 5900
Internet Public port 5901 to Mac B port 5900
Internet Public port 5902 to Mac C port 5900
etc...

1.) is there a limit to how many computers I can have set up (ie: can I keep going to port 5903, 5904, 5906, etc. if needed?)

2.) All my macs are currently configured using DHCP, which I believe resets the IP address upon startup. Will my router keep track of the new IP address, or would I have to constantly reset my router’s settings for the new address?

3.) How secure is this really? In order to connect to one of my macs, a remote user would need my router’s WAN IP address and each computer’s username and password. Is that secure enough, or are the other precautions I should take?

Bob,

Here is my situation. I am pretty much the person that my family comes to for all of there computer problems. My parents live one town, my sister and brother-in-law, in another, and so on. So Lets say I take the steps mentioned above and I am able to get screen sharing to work. Well here is the other part of my problem. Lets saw both my sister and bother-in-law are both logged onto their home network at the same time. I can no longer just connect via the main IP address provided by the ISP since it would not be able to tell my sisters and brother-in-law's laptop from one another. How would I deal with this?

Would I have my brother-in-law set up a static ip address for each of their laptops ( very easy ) then tell them that only one of them can be online at the time, then log onto that computer. Go into their router and designate each one of them a tcp/udp port for each of their IPs, then when I try to connect their laptops using the primary ISP provided IP and designate the port?

Example: vnc://router.address:PortNumberAssignedToUser

I just want to make sure I understand what what you wrote above correctly.

If you are going to use port forwarding, then yes, you have your sister and brother-in-law each using an unique fixed local IP address.

Then you configure their router so it do 2 separate port forwardings:

port forward internet port 5900 to Sister's Mac port 5900

port forward internet port 5901 to Brother-in-Law's port 5900

Now when you want to connect to your either of those 2 systems you would use

vnc://their.routers.address:5900 # Sister's Mac

vnc://their.routers.address:5901 # Brother-in-Law's Mac

There are other methods for accessing remote Macs, such as

• TeamViewer.com (free for non-commercial use)
• LogMeIn.com (free for non-commercial use)
• Hamachi (from LogMeIn.com; free for non-commercial use) - this would create a private VPN between your Mac and your Sister and Brother-in-Law

Hi,

I've tried to set up my router, my parent's iMac and my brother's MacBook as you described in here. I've set the screen sharing on iMac and in router I set that the port 5900 is for 10.0.0.4 address (which is address of my parent's iMac). And I can connect and it's much better than TeamViewer etc:)

However, I've set up the screen sharing on my brother's MacBook and set up the router so that the port 5901 is for address 10.0.0.2 (my brother's MB IP) and I can't connect to his MacBook.

Do you have any suggestions what might be the problem?

However, I've set up the screen sharing on my brother's MacBook and set up the router so that the port 5901 is for address 10.0.0.2 (my brother's MB IP) and I can't connect to his MacBook.

Looking at your screen shot, you need to set the 10.0.0.2 end port to 5900, NOT 5901. Your brother's Macbook is not listening on 5901, it is listening on 5900.

You need a unique port number on the Router side, so you set the Start port number to 5901, but you want to router to redirect all traffic it sees on 5901 to 10.0.0.2 End port 5900. The router is doing the port remapping service for you.

That's what I thought I should do, however, if I change the end port to 5900 it says "The start of Port Number should not be greater than end of Port Number".

And if I change the start point to 5900, it says "Internal Error" 😟

Go to PortForward.com and find your router, then use their instructions to setup port forwarding for your router.

You should be able to forward any port to any other port (high or low).

I suspect that ths interface you are looking at is intended for 1-to-1 forwarding of a range of ports with no port renaming, not forwarding a single port to an internal system where the port number is changed along the way.

I've checked the website but it didn't help😟

This should be my router nad it's setting:

http://portforward.com/english/routers/port_forwarding/ZyXEL/Prestige660HW-T3v2/ defaultguide.htm

The start and end port is just for creating range of ports not forwarding one port to another :-/ Of course, I can be wrong. I'm not that familiar with port forwarding...

If your router will not rename the port in the process of port forwarding, then you could find someone more knowledglable about your router, get a different router, find some information on how to get Mac OS X Screen Sharing to listen on port 5901, use a different VNC server (Vine Server) that allow specifying a different listening port number, or go back to TeamViewer.com.

I was using TeamViewer and I thing it's a great software. On the other site, Sceen Sharing is much better for my parrents. They don't need to do anything and I can connect to their Mac.

I'm about to buy new router for them next month or so, so I will try to set it later.

Thanks for helping 🙂