Windows 7: Able to view other computers attached to ISP in apartment complex

A few days ago I had a brand new router completely crash. Today I noticed in my new routers firewall log of other computers on my isp being blocked from accessing services. Today I tried to connect to a computer on my local network and discovered I can see the other computers connected to my ISP in the windows networking viewer. Is this something I should call my router company about?
Is this something I should contact my ISP about? Or is this something meaning I should beef up security to paranoid levels?

Might want to put a password on that router of yours

if you give the make/model of the Router, I'm sure we can walk you through securing it.

I'm not entirely sure if I interpret your story and picture correctly but... it would seem you have a wireless router that you have left open for anyone to connect on.

So... put some security on it with a password etc. We'll help if you tell us the make of the router...

OK... Brady was faster, again...

It is a Belkin N750 DB. The router is secured and I am waiting on information from Belkin. The wireless has had WPA2 configured from day one on both bands (changed from default), guest account is disabled, MAC address Filtering enabled, and the actual configuration PW was changed from the default password. These definately come in from the WAN half. If I go outside and sit in my car for a few minutes I can see a couple wifi routers with these names appearing. And the list has grown more since this morning. At noon it was up to 15 names. My ISP is incredibly lazy. As in "you have a linksys router and thats why the internet keeps going down" my reply "i have not had that in 2 weeks" "well your MAC says you have it" "ever heard of MAC address cloneing?" and they blame Internet explorer and chrome for everything else.

I would reset the belkin to default.... Once at default, plug in via ethernet and set the security again.

These are NOT clients from wifi sneaking in. These are clients on the WAN portion sneaking in because the ISP has not isolated everyone within the apartment complex.

I got some time today and did some testing, even if the router is unplugged and a computer is plugged into the modem directly, these computers are still visible- minus the router and my other workstations.

With a DDWRT router acting in between the belkin and the modem; the problem vanishes and ony the belkin and my workstations are visible. So I have a temporary fix. My ISP has been contacted and admits the wiring and other equipment in this building and two others is "out of date and has needed to be replaced for some time".

What would be nice is a device thats not as big as the DDWRT based router and with less latency between the belkin and the modem.

Weird... I'm not sure but can't you limit the devices your router accepts by limiting MAC addresses it allows? (to only your own systems/printers)

It will not stop it. If I had been paying attention when I was reading for Network+ as well as checked my Belkin routers firewall log- I'd have had it figured out without haveing to go WTF.

MAC address controls will not work because this is a protocol being fowarded and not actual physical connections to the router.

Most ISP's isolate their users from eachother so creepy things like this don't turn into service calls, police reports, customers feeling insecure and quitting their service, ISP techs realising what they can do and abusing powers, ect. This ISP however does not take their customers seriously and I've only been with them 3 months and I'm wishing I had the security deposit for the phone company or that my complex would let Time Warner in. This actually is a very big security issue. Even if they somehow had accessiblity between the users blocked- it could still lead to a local bored kid haveing a field day at some point.

The Belkin router is examining the traffic and thinking "I am just connected to a switch connected to another router- this traffic belongs." and fowarding it because belkin has yet to fix this in their firmware on this model. While the users don't have a Local IP, they are still listed by windows and linux- albeit unaccessable at this time. A good way to think of it would be going into work where there is a big lan, and connecting a switch to a ethernet socket in the wall. It's basically the ISP is treating the area as a LAN instead of an isolated WAN.

There is only 4 fixes here. 1.Install a cheap router with no real job except to "route" out the SMB packets and isolate the Belkin from the larger WAN. (cheapest)
2.Get a diffrent ISP who takes their customers seriously. (smartest)
3.Hope belkin takes the hint and updates their firmware. (im praying)
4.Buy a hardware based firewall (zywall, sonicwall, ect.) and place that between the modem and the Belkin router. It would be nearly the same as doing #1 but with added features, a smaller box, and thus a little more woth a few milliseconds of latency. (expensive but worth it).