So I just connected to my Model S and I can see the same as nlc found. The connection is 100Mbit and I used the B schematic for my own cable.
NFS
I ran a 'showmount -e' against 192.168.90.100 and there is one NFS mount: /opt/navigon
Mounting it was no problem. I chose 192.168.90.254 as my IP-address.
A simple "ls -al" in the NFS mount:
The VERSION file contained some information which might be interesting:
So Yzadik build this navigation ext3 filesystem for the EU about 1 year ago
It's probably a loopback device on the center screen, but I can't be sure.
SSH
Afterwards I tried to SSH in, but all the combinations I could think of this time didn't work, so I gave up the SSH for now.
But I did do a quick telnet to get some version information:
So it seems to be Ubuntu which is running on there? Well, at least a modified version of Ubuntu.
192.168.90.100 and 192.168.90.101 are both running the same version of OpenSSH.
DNS
On 192.168.90.100 there is also a DNS server running on port 53. It's a recursive nameserver which is open for me:
I also queried to find out which DNS server it's running:
So that seems to be dnsmasq 2.58
That's weird. Since Ubuntu 10.04 (previous LTS) has dnsmasq 2.52 and the current one, 12.04 has 2.59. So this has to be a homebrew version of Ubuntu OR a non-LTS version of Ubuntu.
HTTP
So 192.168.90.100 is running a webserver which serves one file only: nowplaying.png:
We can assume that 192.168.90.101 (the dashboard) downloads this file to display the same image on the dashboard. I tried a couple of HTTP urls, but they all failed.
mini_httpd 1.19 seems pretty old though! 19 dec 2003? But the website says it's the latest version:
mini_httpd
I still would have gone for something like nginx or lighttpd, but hey, it's up to them. It's also available as a package on Ubuntu:
Ubuntu – Details of package mini-httpd in precise
X11 / XDMCP
Using remmina in Ubuntu I was able to set up a X11 connection on port 6000, but it only showed me a blank screen, nothing else.
This was on both .100 and .101. Could be that I did something wrong.
IPv6
I tried to connect to the internal IP's using IPv6, but all three hosts didn't respond on the link-local address I calculated based on their mac address.
Broadcast UDP traffic
I also see all this UDP traffic. I ran tcpdump for about 2 minutes and I'll try to see what it actually contains.