Reconfig'ed home network -- potential problems?

[Rudus]

Hi, all.

I just reconfigured my home network and while on the surface things seem to work, I wanted to check to see if I introduced any potential problems.

Scenario: Two rooms opposite ends of the house. Desktop and Comcast cable modem in one room. Smart TV, Fire, Xbox, misc. wireless devices in the other.

Old setup: I originally had a Netgear router in the same office with the cable modem and desktop. Ethernet from cable modem to router and ethernet from router to desktop. Smart TV, Xbox, etc. all using wifi with less-than-stellar performance.

New setup: Per advice from Comcast tech, I ran ethernet cable from office to family room (approx. 125-150') Moved router to family room with TV, etc. Now have ethernet from cable modem to desktop and ethernet from cable modem to router. Previously wifi devices (TV, Xbox) now wired ethernet from router to devices.

Situation: With the desktop no longer plugged into the router, wife can no longer access desktop shared printer (which I expected; purchased wifi printer), nor can laptops see the desktop (also expected).

Desktop now has a 169.xxx IP address but connects to the Internet just fine with very good speed (90-100 meg).

Question: Is this occurring because both the modem and router are trying provide DHCP? I didn't expect the desktop to be in the same network as those devices hooked up to the router, but I didn't expect to get a 169.xxx IP address, either.

Given that other than the 169.xxx IP everything is working correctly, I'm inclined to leave things as-is for now (until I need laptops to access desktop shares in the future).

Did I introduce any security issues by going from the cable modem to the desktop directly vs. having the router in the middle? Software firewalls are on, etc.

I'd really like to keep the TV in particular wired vs. wifi, as the wifi adapter in the TV seems to be really bad.

Any other configurations that could be suggested? I bought Powerline wifi extenders prior to running the new Cat5 across the house, but I haven't used them yet (again, preferring wired when possible).

Thought perhaps of taking the route of logging into both the Comcast modem and the router and checking DHCP settings, etc. but figured I'd check where I stand first before making any changes at that level.

Insight appreciated -- thanks in advance!

--Rudus

 

[razel]

Hard to decipher how your layout is like. The good news is you ran the Ethernet cable. Ideally you'll want the cable modem married to your WiFi router's WAN port Then your WiFi router/switch attached to everything else. Question is whether you have a cable modem or cable modem/WiFi combo.

 

[Rudus]

Hard to decipher how your layout is like. The good news is you ran the Ethernet cable. Ideally you'll want the cable modem married to your WiFi router's WAN port Then your WiFi router/switch attached to everything else. Question is whether you have a cable modem or cable modem/WiFi combo.

Hey, razel.

The layout you'd described is how things were initially (except being in different rooms, I had no wired connections to TV, Xbox, etc.) The desktop, however, was attached to the Netgear router previously -- whereas now it's connected to the Comcast cable modem.

IIRC, previously: Comcast modem (port 1?) plugged to Netgear yellow port; Netgear port 1 plugged to desktop. Currently: Comcast modem port 1 to desktop; modem port 2 to Netgear router yellow port; Netgear ports 2/3 to TV/Xbox.

I'm fairly certain the Comcast modem is a modem/wifi router combo (albeit an older one). I've used the Netgear router since day one, so I don't know the state of the wifi/network the cable modem provides (never used it, never checked its settings).

 

[JackMDS]

You can not connect to the Internet with 169.xxx IP

There is something else going on. Like two NICs that one is OK and you look at the parameter of another one

http://www.howtogeek.com/forum/topic/169-ip-address

 

[Rudus]

You can not connect to the Internet with 169.xxx IP

There is something else going on. Like two NICs that one is OK and you look at the parameter of another one

http://www.howtogeek.com/forum/topic/169-ip-address

I'll re-check the IP of the desktop when I get home. It's definitely connected to the Internet, so I'll make sure I'm looking at the right NIC and let you know.

Thanks...

 

[NesuD]

Not sure how you can have both your router and your desktop connected to your modem unless your modem is actually a modem router combo. The fact that your desktop has a 169.xxx.xxx.xxx ip means it is getting what is known as an APIPA Automatic Private IP Addressing address. This is what happens when there is no dhcp server available to give it an address. If your Modem is a combo it has been configured to not act as a router and is probably in bridge mode so there is no dhcp sever running on it. Your cat5 cable connections are incorrect for this configuration. All of your devices should be behind your router. The desktop is not. You need to run 1 more cat5 to your desktop from the router. If you are out of ports on your router you will need a switch connected to one of the router lan ports to expand your available ports. Connecting a computer directly to a cable modem with no router in between is not advised. It is exposed and vulnerable connected this way. Your router is your gateway. All devices should be getting access via the router.

 

[Rudus]

Not sure how you can have both your router and your desktop connected to your modem unless your modem is actually a modem router combo. The fact that your desktop has a 169.xxx.xxx.xxx ip means it is getting what is known as an APIPA Automatic Private IP Addressing address. This is what happens when there is no dhcp server available to give it an address. If your Modem is a combo it has been configured to not act as a router and is probably in bridge mode so there is no dhcp sever running on it. Your cat5 cable connections are incorrect for this configuration. All of your devices should be behind your router. The desktop is not. You need to run 1 more cat5 to your desktop from the router. If you are out of ports on your router you will need a switch connected to one of the router lan ports to expand your available ports. Connecting a computer directly to a cable modem with no router in between is not advised. It is exposed and vulnerable connected this way. Your router is your gateway. All devices should be getting access via the router.

I'm going to check the IP in a few hours when I get back to the machine to ensure that I didn't misread the IP as 165.xxx or something silly like that. The cable modem is definitely a modem/router combo with four ethernet ports on the back (one wired to the desktop, one wired to the netgear router, but definitely not using the modem's wifi).

When I went wired from the modem to the router, that was creating the wifi network, but I wasn't exactly sure what was happening with the desktop. It has internet access and a non-192.xxx IP, but I couldn't quite figure out the specifics of what was happening.

Will follow up... Thanks for the comment.

 

[Rudus]

Not sure how you can have both your router and your desktop connected to your modem unless your modem is actually a modem router combo. The fact that your desktop has a 169.xxx.xxx.xxx ip means it is getting what is known as an APIPA Automatic Private IP Addressing address. This is what happens when there is no dhcp server available to give it an address. If your Modem is a combo it has been configured to not act as a router and is probably in bridge mode so there is no dhcp sever running on it. Your cat5 cable connections are incorrect for this configuration. All of your devices should be behind your router. The desktop is not. You need to run 1 more cat5 to your desktop from the router. If you are out of ports on your router you will need a switch connected to one of the router lan ports to expand your available ports. Connecting a computer directly to a cable modem with no router in between is not advised. It is exposed and vulnerable connected this way. Your router is your gateway. All devices should be getting access via the router.

Follow-up questions:

* How can I determine if the modem is in bridge mode? Just by logging in to it?

* The problem at the core is that I ran 150' of cat5 from one room to another to get the TV and Xbox wired, and to do that, I moved the router from my office (near the PC and modem) to the family room. If I want the desktop behind the router, I'm looking at moving the router back to my office with the modem, which means cable modem eth'ed into router, and then 150' of cat5 running from the router to the family room where the TV/Xbox are.

There's my conundrum... If I can only run one stretch of cat5 across the house (which given what a PITA it was to run, I'm guessing is the case), what are my options with that single cat5 connection in the family room? How I can I split it between the TV and the Xbox?

Thanks in advance!

 

[VirtualLarry]

what are my options with that single cat5 connection in the family room? How I can I split it between the TV and the Xbox?

A 5-port Gigabit network switch?

 

[razel]

For cable modems nearly all the ones I encountered. If it's just a cable modem, then it is 'bridged'. It marries itself to whatever you have connected to it's LAN port when you power up. If you disconnect the wire and connect a different device it won't recognize it unless you power cycle the modem.
If your cable modem is a cable modem/WiFi combo then it often will have 4 ports off the back and serves WiFi. Just check the model # online.

It's awesome that you ran a wire. Most people use wireless repeaters or Ethernet over power. It sounds like you just need a switch on one end of your Ethernet wire so that you can connect more devices usually another 4 or 7. Most gigabit switches I see are either 5 or 8 ports and shouldn't cost you more than $30.

 

[Rudus]

Ok, I'm home, and I re-checked things. A few points for clarity:

* So I didn't mis-read the IP, but I did look at the wrong NIC. I do have a 169. IP, but it's not the one in question. Maybe from VirtualBox? A removed HomeGroup? I don't know, but it doesn't matter here.

* The desktop is actually a 10. IP, which makes much more sense to me and explains why the desktop is able to go out to the Internet. Was able to hit \\10.x.x.x from the wifi \\192. machines without issue, so that's good. Will apparently not need the wifi printer I just ordered.

* A gigabit switch seems like it will solve the issue of going from my one long run of cable across the house to multiple wired devices in the family room, so thanks for that suggestion.

Final question being then: The cable modem -- whatever it is (bridge, router, ...) -- assigned my desktop a private 10. IP. Is this setup any less secure than if the desktop were going to the Netgear router?

My two options apparently look like:

a. Leave as-is. Modem's giving desktop a private 10. IP; Netgear router's giving 192. wifi and wired connects to TV and Xbox.

OR

b. Bring the router back to my office. Cable modem plugged into Netgear router. Desktop plugged into Netgear router. 150' run plugged into Netgear router, ran to family room, connected to gigabit switch -- wired connections to TV and Xbox from switch.

I don't mind the extra cost of the switch, but is (a) [my current setup] less secure without the desktop being on the Netgear router? If so, why?

Thanks again to everyone for the help. I think I'm almost there!

PS: Logged into the cable modem itself, and it does not appear to be in bridge mode, for what it's worth. There are firewall settings (which are on), and wifi, so I'd guess this is as secure as have the desktop connected to the Netgear router -- but feel free to correct me if I'm wrong.

 

[razel]

Devices connected to your Netgear are on a Double NAT. That's arguably more secure.... well just more labyrinth. But you'll want to fix it so that all your devices are on the same network. Two ways to fix it. Recommended is to change your cable modem to bridged mode. The other way is to change your Netgear to Access Point mode.

 

[QuietDad]

Try this. With from the modem, connect one port to the PC next to it and one port to the run to the family room. With the Netgear in the family room, connect the cable from the modem to one of the LAN ports along with all the other devices in the room. That, in effect, makes the router a switch. Please post the make and model of the modem so we can figure out exactly what it is

 

[simas]

"


New setup: Per advice from Comcast tech, I ran ethernet cable from office to family room (approx. 125-150') Moved router to family room with TV, etc. Now have ethernet from cable modem to desktop and ethernet from cable modem to router. Previously wifi devices (TV, Xbox) now wired ethernet from router to devices.
"

stupid question - why not buy an ultra cheap switch/hub for the second room and forget about it? what may help you (as it helped me when I looked at network) is
- writing down what logical components I expect to have
- write down what each logical component is expected to do
- write down what physical devices serve as what logical components for you (it does not have to be done to one and for almost all consumer devices would not be one to one).
- adjust your network accordingly

i.e.
firewalls set up rules that control traffic flow and/or filter it
router connects your network to other networks (i.e. internet)
switch allows devices to talk to each other
(wireless) access points extends your network by allowing devices with appropriate hardware to connect

your 'router' could try to play all of the roles above as consumer device (basic firewall, switch for devices to talk to each other, router for internet connectivity), or you can delegate this to specific devices and swap them out as needed.

if I were you, I would move the router back to where it was, configure whatever you got from ISP/Comcast in bridge mode, and put a 4 or 8 port switch/hub (ultra cheap) on the other end of the cable you run. this would avoid f4cking around the ISP device or weird network things you are doing now (unless it is by intent).

 

[Rudus]

Thanks to those who chimed in. My current setup echoes the setup suggested by QuietDad (router acting as a switch in the TV/Xbox room).

I don't have the model number on me, but the cable modem is definitely a combo device (modem, router, wifi, etc.), and other than currently not being in bridge mode is functioning correctly (or at least acceptably).

I'm going to look at putting the modem into bridge mode, but right now, having the router in the same room with the TV/Xbox acting as a switch (with two ports to spare) seems to be fine. I'll keep the wifi printer, forego a "true" switch, and call it a day.

Thanks again. Will follow-up if anything goes awry, but I think this will work.

--Rudus

 

[razel]

Only one more thing to suggest for your WiFi. Ensure that you only have one WiFi running. Chances are both your cable modem's WiFi and your Netgear WiFi are up and probably competing. If the tech was/is any good he'd probably turn the cable WiFi off.

 

[Rudus]

Only one more thing to suggest for your WiFi. Ensure that you only have one WiFi running. Chances are both your cable modem's WiFi and your Netgear WiFi are up and probably competing. If the tech was/is any good he'd probably turn the cable WiFi off.

I was under the impression that disabling bridge mode would disable wifi on the cable modem, but IIRC, there were separate settings for bridge enabled/disabled and wifi enabled/disabled. What is the distinction between the two? Just in the event that I wanted to disable wifi but leave on DHCP, etc.?

As for the Comcast tech... All he was called out to do was to run the Cat5. When Comcast told me they'd run coax but not cat5, I ended up doing it myself, and the tech just commented on my situation casually. He didn't really scrutinize things (to no fault of his own).

Thanks again.

 

[razel]

What settings disable what depend on the modem. In general once it's on bridge mode, WiFi is often disabled. If not, simply disable it.