BARCO DP2000 question

[Steve Guttag]

kein problem.

[Marco Giustini]

ahah yes, the weird trick of the wrong serial port!

Well done, glad you made use of the software I send you to make a DP2000 happy again!

[Dave Macaulay]

Likely it was on Dolby DSS IP address, they use a separate /25 network segment for each screen - set up so one screen's devices can't communicate with devices at another screen. No idea why... is addressing stuff correctly that much of a challenge? We always use a /24 or /23 network segment which works great and allows a remote tech with login to a PC on the network to access everything.
And... originally a DSS server could only use network communication with Dolby devices, anything non-Dolby had to use serial. Later they opened the network to other stuff but made actually doing so a nightmare.

[Leo Enticknap]

That was the factory default for a DSS server (192.168.X.129 / 255.255.255.128, where X = the auditorium number), but you could change it to anything you like. I also don't understand why they did the half a subnet thing, unless they anticipated that you might want to use the other half as a DHCP range.

But I can see why they wanted the different auditoria in different subnet for the management LAN, with each unable to see each other: it reduces the risk that you'll accidentally talk to the wrong projector, server, etc. when doing something. I've seen this happen in theaters, that use an IP scheme along the lines of 192.168.100.1XX, 2XX, 3XX, etc. In the DSS scheme, only the "theater" LAN (media, plus some server management functions using the DSS TMS) has a single subnet for everything.

[Steve Guttag]

No, no no...you all missed the "beauty" of the original DSS IP scheme. One can communicate with any device, providing you have a router on the "Theatre Network" to create the routing table. Each server has its own router internal, that is used as a gateway. So, for instance, for theatre #3, one would define a route that all 192.168.3.0 subnets use the gateway 192.168.241.5 (server 3's Theatre IP. You can then get to any Auditorium 3 devices. You get a virtually unlimited number of IPs as each auditorium would have 128 IPs.

My guess is that they cut it in half because they were on the same subnets, otherwise, that most out-of-the-box devices that might be in the cinema (192.168.1.0...theatre 1 is a very common default subnet). I always switched mine to 100+ the screen number, so 192.168.101.0. It wasn't a perfect system but it did work, particularly on smaller plexes. The single Theatre Network scheme did perform poorly in bigger plexes as the one "TMS" is running everything and moving content on that one network. But it did mean that one need only run a single network cable rather than the more common two cables (management and media).

There was an elegance to it all but I'm sure less than 10% configured their networks to allow full communication.

[Marco Giustini]

oh yes, I loved the "enclosed" auditorium network which was accessible via the server itself via IP forwarding!

[Stephan Shelley]

The half address space dates back to the DSS/DSP 100. The network connection between DSS & DSP was 192.168.X.1 for DSS and 192.168.X.2 for DSP. There were rotary switched on the back of the DSP to change the X auditorium number. Only reason I still know this is I still have 2 DSP/DSS 100s in regular daily service.

[Ioannis Syrogiannis]

Is there a little switch or knob somewhere that determines whether, via a LAN connection, you're talking to the projector or the TI board (which has a separate IP identity on Series 1 machines)? There is on some NECs.

I understand I am getting out of subject now, but I am curious: I don't quite follow how a knob or switch would help, since the IP of the TI board is, as you say, different. The (multiple) RJ-45 port ethernet switch would do the connecting to both, just as well. Having a different software to connect directly to the TI, made the things even more straightforward.
I remember all NEC S1 projectors I made the acquaintance of to have two ports. That made life easier, but NEC dropped the idea on S2. Wouldn't the internal (ethernet) switch make the work that you describe? Or wasn't any there?