Canal Digital and Linksys WRT54G

**!const** · 12-02-2009

Have broadband access from Canal Digital. Running a Thompson cable modem. Seems as if the IP addresses I get on the computer connected to this is "public" that the cable modem does not have any dhcp / router functionality, but that it is Canal Digital who give out ip addresses. Correct?

Have set up a WRT54G router, but to avoid double NAT'ing, I use one of the LAN ports on the cable modem and disable dhcp and firewall in this router. Use the fact that an access time. Linksys require that I use a static ip for the router address (local access), so I have given it an address as "similar" on the Canal Digital hands out, and this seems to work fine. But it is not surprising that this works? Can I risk at the IP I have assigned static with Linksys to collides with another computer on Canal Digital's online?

Actually, it is the individual computers that are connected to the Canal Digital exposed directly on the Internet - there is no NAT'ing in the cable modem - the computers have the same ip addresses "local" as "public" ...

Some thoughts about this?

**Baltazar** · 12-02-2009

CD (Canal Digital) delivers only the modem, so you will not have problems with the routing of the ports, etc.. Advantage for some. (Those who run their own server, or people with just a PC.) But the disadvantage for those with less knowledge about the computer, and will connect several computers.

I believe it is better that an ISP provides the modem, and often assigns IP rights in. Then it allows us to put our server directly to the Internet without fiddling. But it is also beneficial for people with just a PC, then they let the problems shown ever need a port open all the way into. These people needs router to connect to more than 1 pc when people have the opportunity to choose for themselves. (Do not turn in with a bad router supplied by ISP.)

The disadvantage is obviously that we are more exposed, when everything is open in principle. But with a good software firewall, and updated OS should not this be a problem.

The fact that you have set an IP on your WRT54G, but it can provide you the trouble appeared to be sending data to the real owner of the address. Not sure if this will create problems for others, then I'm not sure how the CD (Canal Digital) will route their network. But I am quite sure that they have added features that prevent you from "break" for a 3rd part.

**Gunilla** · 12-02-2009

Have the Canal Digital here, too - using a WRT54GL behind the modem.

But I have connected the modem to the WAN port on the router so it works as usual routes of 192.168.1.1 and it is a normal internal network. Is not a problem with double-NATing, for everything is going right through the Canal Digital-modem. Ports must only open in the router.

**Aleksandra** · 12-02-2009

As mentioned above so it will not double-NATing, so it is OK to use the router as normal (wan in) and either forward ports as needed.

I think personally it is a confidence to have a hardware firewall in case you should turn off the software firewall when you are experimenting.