Need some networking help!

[brourke228]

Sup guys. I've been working on a new way to connect my Dreamcast. Though it isn't particularly economical, it will be pretty damn convenient if it works. So let me start off by saying that at the moment I have LAN connection, but no internet going to DC.

Here are the materials:
-3Com 56K LAN Modem (Netopia R2000 and R2020 also appear to be viable alternatives) ---> http://www.3com.com/products/en_US/deta ... =3C886A-US
-Cable/DSL Modem
-Broadband Router
-Phone Line Simulator (I'm using a Teltone TLS 3)
-Network Switch (with uplink)
-Dreamcast (Duh)

Documentation for the 56k LAN Modem is at the bottom of this post.

So most of you likely have no idea what this 56K LAN Modem is. Basically what it is, is a 56K Modem and a 10Mbps router combined. It allows a Dial-up (Dial-out) connection to be made and shared between PC's on the LAN. Or... a Dial-in (Dial up server) connection from a remote 56k modem to your LAN. As such, it is also controlled the same way as a router via web browser. For more info check out the product support page.

So here is my current setup:


So let me explain this set up.. First you have Dreamcast and a B or A modem( doesn't matter) and this connected to a Line port on the phone line simulator. And then another Line port connects the phone line simulator to the 56k LAN Modem. The LAN Modem has 4 10Mbps RJ-45 ports for LAN. There is no uplink port, hence the need for a network switch with one equipped. Since, from what I understand 2 routers can't work together on the same LAN without it. So one LAN port is connected to a LAN port on a network switch. THen another ethernet cable goes from the network switch's uplink port to a LAN port on my broadband router. DHCP is disabled on the 56k LAN Modem and is given a static ip address (192.168.1.2 in my case). My broadband router is assigned the ip 192.168.1.1 .

So with this current set up I am able to access as well as ping the 56k LAN Modem router page at the ip address 192.168.1.2 on all clients of my broadband router on both LAN and WLAN. I belive the LAN Modem has internet as well because when I try to update the firmware on it it says no new firmwares available instead of giving an error, but that might just be how it works.

Here are my current settings for the Dial-in connection with the LAN Modem:



I currently have the LAN Modem set up to answer the Dreamcast automatically on the first ring. As shown here and in this video, I am able to connect with dreamcast (sorry for the bad video quality):
[youtube]http://www.youtube.com/watch?v=Zzi-fAGO1PM[/youtube]


The way I understand it, the 56k LAN Modem extends its LAN over the dial up connection when being used for Dial-in. However when I establish a connection Dreamcast doesn't seem to be able to access my broadband router or the 56k LAN modem at 192.168.1.1 and 192.168.1.2 respectively, or the internet for that matter.

If you're good with networking much help would be appreciated.

[brourke228]

UPDATE: I'm able to connect to the 56k LAN Modem's browser interface now with the DC browser, but I still cannot connect to my broadband router or the internet. It appears that Dreamcast needs to be on a subnetwork. Here are the updated settings:

[BlueCrab]

If I had to guess, I'd guess that the "LAN Modem WAN IP" shouldn't be the same thing as your normal broadband router (which is 192.168.1.1, I'd guess by the DNS entry). Perhaps try changing that to 192.168.1.2 or something else on the 192.168.1.xxx network?

[brourke228]

Those are just the settings for the actual dial in connection. The ip of the lan modem is actually 192.168.1.2 already. There is a separate section for the IP settings of the LAN Modem itself. Here:


I'm going to attach the User manual and the documentation for dial-in access which is separate to my original post. It says in the dial-in access configuration doc to leave the "LAN Modem WAN IP" blank, but if i do it does not change anything (still connects to lan modem, but not internet or my broadband router).

[BlueCrab]

The only thing I can think of is that its some kind of problem with the way you have things connected to the main network via that switch, especially since you can access the LAN Modem's page from the Dreamcast, but nothing else. I don't know what to suggest beyond reading through the documents again and seeing if you missed something in it...

[brourke228]

Actually I think just figured it out. After reading through the dial in configuration documentation again. In order to ping Dreamcast from one of my PC's i need the 56k LAN Modem to be its default gateway. So with my desktop's gateway set to 192.168.1.2 i can ping dreamcast now at 192.168.2.151 (shows 151ms). So what I'm thinking is I need some sort of network device that will connect to 2 different gateways and pair them together, kind of like how one could share an internet connection between 2 NIC's on a PC. Since I don't think any data is transferring between clients on my LAN and the 56k LAN Modem's "Remote 56k client" unless the LAN Modem is their gateway.

Would a network bridge fix this?

This is how the dial in connection is supposed to work:


So I gotta trick the lan modem into thinking my broadband router is a LAN client so it transfers internet traffic between DC and my router.

[Bob Dobbs]

It would need to be a transparent bridge.

[brourke228]

maybe add a DHCP server on another VLAN??

or add 2 routers after your main WAN and use a straight-through cable to connect them together, disable dhcp and edit IP settings etc.

You mean have a third router that they both connect to before going to the internet? Currently DHCP is running only on the broadband router. I disabled it on the 56k lan modem so there werent any network conflicts and set its IP to 192.168.1.2 . The broadband router is 192.168.1.1 .

The problem I'm having is that this lan modem wants everything to see it as the WAN . Like i can connect it to another network but unless all the clients on that network have the lan modem as the default gateway, no data will be transferred between them. If i have something that works like 2 NICs together then it might be able to see them both as gateways and share the internet connection. I don't want to have to use a computer to do this though.

[brourke228]

Well basically i can connect the Dreamcast which is under an NAT connection created by the 56k lan modem. It has the address 192.168.2.151 . From the dreamcast I can access the 56k lan modem at 192.168.1.2 and any device on my LAN that has the 56k lan modem set as its default gateway. I have tried removing the switch and connecting it directly to the router which made no difference. I did not mention the router I'm using has dd-wrt firmware on it so it probably has a lot more options than a normal router would, it might have an option for vlan. However my knowledge of networking is limited.

http://www.dd-wrt.com/wiki/index.php/VL ... rt#Netgear

The model is wndr3300

So from what I understand from just reading bout this breifly. A vlan will allow me to use one of the LAN ports on my router as a second WAN port? And i can set a gateway to it which i would make the 56k lan modem. Is that correct? Sorry this is new to me.

This is the only page that references to vlan on my router:

[brourke228]

Okay, it appears this router does a lot more through "commands". I'm reading through the documentation now..
http://dd-wrt.com/wiki/index.php/VLAN_D ... nternet%29

http://dd-wrt.com/wiki/index.php/VLAN_B ... d_WAN_port

Alright so it looks like i will have to do this through a terminal with the "telnet" command. I don't have time to work on this right now, but I'll try and go through this during the week and report back.