Yosemite Messages Screen Sharing Router Type: Port Restricted

Question

I want to do Screen Sharing via Messages as newly enabled in Yosemite (through Messages...not the Buddy List).  Unfortunately, it fails.  I run Connection Doctor under Video in Messages and see that I have an issue with the message "Router Type: Port Restricted".  I would like to see "Full Cone".
What do I need to do?
I am on AT&T U-Verse running a Motorola NVG589 modem. I have the wireless disabled on the NVG589.  The NVG589 is connected via ethernet to my Apple Airport Time Capsule (the tower model that is 802.11ac).  The Airport Time Capsule is set up in Bridge Mode - so as not to create Double NAT but to offer 802.11ac wifi speeds and to provide Time Machine backups.
I have connected directly to the NVG589 modem and gotten the same "Router Type: Port Restricted" message.  I assume I must open a port/ports on the NVG589. If so...what are those ports?
Any help would be greatly appreciated!

Answer 1

Hi,
The Messages app in all versions up to Mavericks only Screen Shares with AIM to AIM and Jabber to Jabber contacts as well as Bonjour connections on your LAN.
It is based on those accounts that do Video and Audio Chats within the app.
The iMessages invokes FaceTime to do Video and will not do Screen Sharing.
However as you say there is this info:-
Share a conversation —
and your screen.
Now you can share your screen with the person you’re chatting with. Then you can go from iMessage conversation to screen sharing with just a click. You can easily do things like collaborate on a presentation with a colleague, browse the web with a friend, or select airplane seats with your spouse. And Messages automatically initiates an audio chat when you start a screen sharing session, so you can talk things through while you’re at it.
On checking the icon to Screen Share does appear in iMessages conversation Details option
Notice the slightly diminished ("greyed out") quality to the Screen Sharing icon.
It appears it only works to other Macs.
The Buddies menu also has the option greyed out.
Routers
My Network Status looks like this.
The Bandwidth Limit is set in Messages > Preferences > Video/Audio pane > Bandwidth Limit.
Setting it to 500kbps is over what it needs to do 4 Way Video chat as Host.
When it is a really fast connection to a much slower Buddy it can help  and also with higher speeds come higher variances which and cause havoc.
There are four main type of Router  type as this refers to them.
http://en.wikipedia.org/wiki/Network_address_translation#Methods_of_port_transla tion
Port Restricted is just as effective as Full Cone.
I have had it show up this way on a  Thompson-Alcatel 510v4 when I was first On line in iChat 2 and Netgear device I forget the number of, a Sagem Fast2504 from Sky my current internet provider when I had DLS and the current Fibre Hub that they supply.
I have UPnP set as the method to open the ports needed.
This allows the computer (apps) to tell the router which ports to open.
They will also close after periods on Non use.
Router that do UPnP advertise the fact.
You can reduce the number of devices that happens through (Hops). The default setting is normally 4.  Router to computer counts as 1 Ethernet hubs don't count. But large LANs with more routers (Subnets to LANs) will count as more Hops.
Ports.
Most devices have the first 1024 port open (there are 65355 in total).
These lower numbered port handle things like Web Browsing on port 80.
FTP on port 21 and 22
Some Outgoing Mail servers on port 25
Secure web connection on port 443
and so on.
Messages and FaceTime Video chats use ports above this.
These are the one you tend to have to allow.
Video uses 5678 to send invites then moves to port 16402  (or one from a group of 10 ports below this)
10:02 PM      Saturday; November 22, 2014
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