Change Your Password - No, not that one...

I've encountered this change router password subject in articles by several other tech newsletters. I promptly changed my Linksys (non-wireless) router ONLY TO FIND I COULD NOT CONNECT TO THE INTERNET! An ISP page came up instead wanting to run a diagnostic that ended up with a "call us" result. So I reset my router password but still got a failed connection.

So I called AT&T/SBCGLOBAL.NET (using a number I already had not the one I was given - paranoia pays, y'know!).

My ISP told me that there had to be some kind of password agreement with my user account...but several attempts by them to get things working again ended in disconnecting the router and straight connecting to the DSL modem.

There seemed to be some concern that the internet light on my modem was not lighting up (but I can tell you that it never did when the previous router and modem connection had ALWAYS worked).

Efforts focused on "bridging" and not bridging and PPO and PPOea, etc. and stuff the tech was vague about left my head spinning.

But I had a working modem-direct connection and since I had to leave for an appointment I thanked them, left it at that, and moved along. Later, I reinstalled the Linksys using the CD (which crashed 1/2 way through the install). In frustration, I cold booted the PC with the power off on the modem and the router. Waited a minute and powered them on and VOILA, everthing was working again.

Now, about the paranoia part...so now my internet light on my modem is always on and frankly I'm a little concerned that I'm less secure than I was before since I imagine that my IP address is not that of the router but of my PC.

Should I be concerned. Should I go back to the ISP? Back to Linksys? Back to bed?

Thanks.

Thanks Leo and all of you commentators!
I first logged onto my ISP's website and went to their FAQs pages. There, they showed me how to get to my Netgear router webpage from which I just followed the step by step instructions to set a password of my own and by the way disable the wireless function altogether!
Drastic did you say?
I never overlook my teacher's advices!
Cheers to all!

Thanks for your reply Leo.
I didn't realise before, that port scanners had to know what service the port was being used for to exploit it. See, I am learning stuff! /grins.

Leo wrote:
"if it does attempt to probe that (random - ed) port the scanner has no real way to know what service "language" (like SSH) it should talk to the port to make it operate"

Snipped from Wikipedia:
"A port may be forwarded for use by either the TCP protocol, the UDP protocol, or both."

I guess I just assumed that port scanners these days would be intelligent enough to know that non-standard (hence forwarded) ports, must be using one or both of the accepted TCP or UDP protocols.

But that aside, say a port scanner finds a port that it knows what service it's being used for, say POP on port 110, or NNTP on 119. Aren't firewalls configured to accept connections (in the appropriate protocols) through these ports? Can't it then exploit them? and if not, why not? I understand that some protocols are inherently secure, like SSH.

I'll also understand if you don't reply to this one, as it is a little OT. Or maybe there is a more appropriate discussion thread to post this to?

But cheers anyway Leo, for the invaluable understanding and advice you impart.

Oh BTW Steve, are you sure you didn't inadvertently change your internet account password (the one your ISP gave you), and not just the modem's login password?

Another thing to consider is that, even if it only has one physical port, your "modem" is *also* a router. It serves up LAN IP addresses, as does your "router". If by chance the router tries to use the same IP address as the modem (and I have seen that happen) you will have an IP address conflict. Resulting in the loss of your internet connection. But in any case, your modem/router is what's facing the internet, so it's a "no" to your paranoia question.

I really hope Leo doesn't mind if I point you towards a page at portforward dot com. Learning about port forwarding has increased my knowledge of networking appreciably. Even if you never do port forwarding, this stuff worth knowing. You will at least learn why teck support tried to "bridge" your router. /smiles http://www.portforward.com/help/doublerouterportforwarding.htm

Best regards to all. ~Adrian (Lan Down Under)

"But that aside, say a port scanner finds a port that it knows what service it's being used for, say POP on port 110, or NNTP on 119. Aren't firewalls configured to accept connections (in the appropriate protocols) through these ports?"

No. The fundamental difference here is incomming versus outgoing - yes, you may use 110 for POP3, but that's an outgoing connection from your PC to your mail server. Your firewall continues to block 110 incoming connections. In reality there are typically no valid incoming connections in a normal home or small business setup. All the connections you make are outgoing - i.e. initiated by your computers connecting to an outside service.

08-Mar-2010

Actually, for some routers, there might be several user/password combinations just as administrator, guest, etc. accounts in Windows. Example: admin/support/user in one of my modems. These may be disabled or not. If not, defaults may apply. I remember a friend claiming nobody could access his PC because of a fancy user/password combination he was using, but he simply forgot the other defauly accounts including the admin. Same goes true for many modems and should be checked and modified or disabled.

Leo, I was able to find the router website and changed the password successfully. BUT... I could not find how to log OFF of the router setup page once I was done. I close the tab (firefox) and re-enter the ip address for the router set up and it goes right back in without asking for my password. How so I successfully LOG OFF this page?

Again that too depends entirely on the router. Look for a log-off button or link. If there isn't one then completely closing and restarting your browser often does the trick.

10-Aug-2011