RutSum

MTNL Network Madness – People Living Over 30 Km Away On My Wireless Network

Yes, it was a hellish nightmare, and its not ending anywhere soon. I recently got a wireless router on rent from MTNL, so that I could have a wireless home network and could roam around with my MacBook anywhere in my house. I created a network, and to ensure maximum security for the network and to prevent misuse, I used a 3 step security procedure –

1) I encrypted the network with a WPA2-PSK key. My key is over 30 characters long, and is in no way easily brute-forceable.
2) I disabled broadcasting of my SSID (which basically makes my network invisible, unless explicitly dug for)
3) I enabled MAC address filtering, and added my Airport Mac address to the filter, so that the network could be accessed only from my MacBook.

But 2 days ago, the nightmare started. I saw around 25 computers in my local network (or popularly known as ‘Network Neighborhood’). Many out of these computers had names which are normal Hindi names of people, but I did not recognise even a single one of them as my neighbors. I was shocked, but my first impulse was that my wireless network had been compromised. I rebooted my router. I joined my wireless network again. The computers came back. I changed my WPA2 key, and rebooted. No change. Just some of the old computers disappeared and new ones appeared. All this, I did by accessing my router settings from my PC. My default gateway is 192.168.1.1.

The one that is blurred out is my own PC, which SHOULD be there, as it is in my local network.

Next, I connected to the wireless network (my own network and not somebody elses network) from my MacBook, and tried accessing my router settings, by using the same address (192.168.1.1), but again, I got another shock. I was directed to a totally new firmware page, which definitely did not belong to my router. I tried in the default MTNL username and password combination (which is admin/admin) and it worked. From the WAN configuration settings on that page, I got the phone number of the guy to who that router belonged. I did a cross check on that number from MTNL’s online directory, and it turned out to be a number from Dwarka Sector 7. This was another shock, as I live around 30 Km away from Dwarka, and there is no way my wireless router could have that long a range. Five minutes later, I rechecked the same page again (192.168.1.1). This time, it redirected me to another, 3rd new page, which again, did not belong to my router. I tried the admin/admin combination again, and it worked. This time I found another number, which again belonged to a different guy, but from Dwarka Sector 7 AGAIN (but different apartments/societies). This process repeated itself 2 more times, each time with a unique, new guy’s router. I have noted all the numbers down and have a record of them. I then rebooted my router again, and since then, 192.168.1.1 gives me my own router, and not anybody else’s router. Another thing to add here is that in this time, if I checked my IP from an external site such as whatsmyip.org, it gave me that other guy’s IP address, from my MacBook(I know because it was mentioned in that guy’s router config page). And when I checked my IP from my PC, whatsmyip.org gave me my own IP address (listed in my own router config page). What this means is that even though my PC and MacBook were using the same connection to connect to the internet, they had different external IP addresses, temporarily, which is theoretically IMPOSSIBLE. A single line cannot possibly have 2 different IP addresses at the same time.

I tried accessing these computers from Mac OS X, but got nothing, because I expected most of them to be on Windows. I rebooted my Mac into Windows Vista, and saw that the same machines existed there too, in the Network Neighborhood. I tried accessing them from there, and indeed was able to see people’s shared files (obviously only those who had acutally shared their files). I saw shared printers, and even tried printing on one of them, which was successful.

All this made me sure of one thing – this was an MTNL screw up, and these guys weren’t even aware that they were connected on a network. Sometime in between all this madness, I felt as if someone was stealing my bandwidth – my connection was choked. I realised it could be due to someone copying files from my public SMB shares, which I immediately took offline, and indeed, the choking was over.

The madness isn’t over yet, the people are still on my network. In my opinion, this a screw up on the part of MTNL, with different clients getting assigned each other’s IP addresses, causing the whole screw up. If 2 people have the same external IP address, then they will be on the same local network, and hence all the machines I could see were actually on somebody else’s local network near their home. I know there are a lot of things still to be cleared out, but nobody seems to be stealing my bandwidth right now.

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