Network setup, with Cable Set-Top box connected

Hey

I got a problem with my network setup, which i cant solve myself. The problem is, that ive just got my hands in a HDTV Set-top box, which needs to have a connection to a specific IP-address, in a diffrent net, than i get my internet connection from. So atm the setup sounds like this:

ISP-Cable --> Modem --> Switch --> Router/Wireless
. . . . . . . . . . . . . . . . . . . . . --> Set-top box

I would very much like to get that switch out of the setup if possible ?? As ive already told, the Set-top box, needs to connect to a specific line, in a diffrent net, than my internet connection is carryed through. I would like to know if it is possible, to get the router to have a passthrough line, not going through my internet connection as the rest of the network ?? Looking like this:
--- Wan --- Router --- Internet connection
. . . . . . . . . . . . . . --- Set-top box connection

Ps. hope you understand what i mean

 

The switch should not be there any way. The real issue is that you are not using their router is my guess and the NAT is blocking the udp ports that the settop box is looking for. You connect to places all the time that is not in your subnet. So it may not be pulling Gateway info to get out.

Put the settop box in a DMZ should correct the issue. If that does not work try VLAN.

 

And how can i do that ? Im quite a n00b when it comes to networking

Another problem, is that the set-top box needs to have a specific IP-address it self, can I somehow manage to setup the specific ip's for the devices connected to the router ??

Btw its a zyxel zyair b2000

 

Setting it to a specific IP will do you any good. Since it goes through a router the box will have a private IP address. Mainly you do not own a public IP except the one that is assign to you by your ISP. Every box I have every worked with, works with private IP's issued by the routers DHCP server.

From what you have told me tells me this unit was stolen from some other network. And you are not paying for a digital tv service. So I'm going to stop at this point.

 

Erhhmm... this is not a stolen box, its a new Cabel-service delivered here in Denmark by Stofanet... A Motorola ( http://www.motorola.com/mot/doc/6/6346_MotDoc.pdf) box which needs to have a specific ip for receving information by Stofa, sideways that its reciving signal through DVB-C... So no its not illigale

Stofa them self claims it is not possible to avoid the switch... So I asked advice in here, to see if it was not just the technichan that didnt knew, what he was talking about... So please think twice before accusing me for watching illigale telly...

 

Sorry if I offended you, here in the US things are quite different.

That tells me the box will pull the IP from the switch, nothing to do on your side, unless the provider instructs you to. Your setup is totally different that what we use here. Switches are not used between the modem and router. Only to expand a larger network, not at the local user level.

Once you go through the modem you have a converted a coax signal to a cat5e network (digital) signal. Going through the switch next tells me the box is all ready programed to work on their network. The router has a built in switch too, but also does NAT translater.

Here in the US all of the digital systems I'm familar is either connected directly to the coax and the on screen prg and video on demand is handled through the network side. All of this is handled with a NIM or a router with special firmware to tie the 2 networks together.

I hope this helps you to under stand on how networks work.

 

No problem mate, just got a little sad, being accused public for watching illegal telly

As far as im informed, this system works in the same way, the cable signal, deliveres the tv-channels and the i-net carries the EPG and Video on demand and such. I think the linking with the 2 networks, happens in the box (directly wired to cable-net and also modem (which now seems to carry 2 signals, one for internet and one for the set-top box), as the switch just splits my line from the modem. Ex. my i-net normally, not having fixed ip, uses 62.xxx.xxx.xxx and the set-top box has a predefined ip 10.xxx.xxx.xxx.

And as you say, my Set-top box needs directly to be wired to the modem (also cable), so it gets direct connection to the ISP, as it already has a predefined IP it needs to work.

So as the network dummy I am, I was wondering if it can be true, that i need that switch. I know that the router can work as a switch, but then the idea with it, routing out my Internet connection to my computers at home is gone. Or can it do both at once ??

 

You'll probably need to use a switch. You basically have to split the signal coming out of the cable modem, which is what the switch is doing, before it gets to the router, because as blue68f100 has stated earlier, once it gets to the router, you'll be on the router's private IP subnet. So your set-top box cannot be behind the router.

You can use a router as a glorified switch, but switches are relatively inexpensive.

 

I do not not see how it will work, with your cable running on public IP (62.x.x.x) and your settop on a private 10.x.x.x connected to a switch before your router. I can see it working if the router is setup to use same subnet as the settop box, 10.x.x.x private IP address.

These are all of the private IP available:
From 10.0.0.0 to 10.255.255.255
From 172.16.0.0 to 172.31.255.255
From 192.168.0.0 to 192.168.255.255

Do a quick test and plug the settop box into the router then look at the dhcp log and see if it show up. My guess is yes. If the settop box did not pull an IP from your router in default condition. The provider should have told you what subnet is required. Then I would reconfigure the router to use the 10.x.x.x subnet provided to you. Remove the switch out of the circuit, or put it behind the router to expand your system. Then set a DMZ for the set-top box.

If the set-top box has connections for coax and net? I would hook it up like a normal box and make the net connection into it. I would almost bet the set-top box is using DHCP and will grab any public IP address the routers gives it. I do know on my system that all of the VOD and onscreen programing uses 2 services L2TP and TFTP. So these ports are forwarded to the IP of the NIM in my case. The NIM is what ties the coax and net together. So putting the settop box in a DMZ should take care of any port forwarding.

For security reasons create a VLAN in put the settop box in it once you get it working. That way it will have a different subnet and can not bridge to your pc's.

It's strange that they gave you no instructions on how to setup the box.

 

Okay, ill try looking into it

Well, the informations they gave me was just to use the switch, because it will not work behind a router :S

I think I might have explained it in a wrong way before. My ip to outside world is 62.xxx.xxx.xxx (guess thats the IP my Wan also have) and the set-top box's predefined ip is 10.xxx.xxx.xxx. But ill try to make a setup looking like blue68f100 described and hope it works