Virtual Servers list and Teredo

Forums › LAN (ethernet/Wifi/routers/Bluetooth) › Virtual Servers list and Teredo

colinuu

97 posts

Master Geek
+1 received by user: 4

Topic # 111128 24-Oct-2012 23:07

Hi,

This is the virtual servers list in my new router:
NameWAN PortLAN IP AddressLAN PortProtocolStatusModification
HTTP80192.168.1.5180TCPOn

FTP21192.168.1.5121TCPOn

Teredo50707192.168.1.10050707UDPOn

Teredo63437192.168.1.10163437UDPOn

Skype UDP at 192.168.1.51:55866 (2120)55866192.168.1.5155866UDPOn

Teredo52624192.168.1.10052624UDPOn

Skype TCP at 192.168.1.51:55866 (2120)55866192.168.1.5155866TCPOn

Teredo63148192.168.1.10063148UDPOn

Skype TCP at 192.168.1.102:61018 (2114)61018192.168.1.10261018TCPOn

Teredo57629192.168.1.10357629UDPOn

Teredo65102192.168.1.10165102UDPOn

Teredo62694192.168.1.10562694UDPOn

Teredo58526192.168.1.10158526UDPOn

Teredo56618192.168.1.10056618UDPOn

Teredo53715192.168.1.10153715UDPOn

Teredo56235192.168.1.10356235UDPOn

Teredo59912192.168.1.10159912UDPOn

Teredo57244192.168.1.10057244UDPOn

Teredo60484192.168.1.10060484UDPOn

Teredo49703192.168.1.10349703UDPOn

Teredo58496192.168.1.10158496UDPOn

Teredo56891192.168.1.10156891UDPOn

Teredo60120192.168.1.10360120UDPOn

Why so many entries for Teredo, including multiple duplicates for same IP numbers? It looks like the list just continues to grow and grow. I'm not sure that I like having so many ports open, also I wonder how many lines can exist before the router starts falling over.

Should I worry?

Cheers,
Colin

Edit: Sorry about the bad formatting, it was a nice table when I created the post...

ubergeeknz

Fully Operational
3343 posts

Uber Geek
+1 received by user: 1088

Trusted

Vocus

Subscriber

Reply # 706024 24-Oct-2012 23:32

Teredo is used for IPv6 tunnelling, if that rings any bells.

freitasm

BDFL - Memuneh
58935 posts

Uber Geek
+1 received by user: 10300

Administrator

Trusted

Geekzone

Subscriber

Reply # 706075 25-Oct-2012 07:44

Perhaps if you told us more than just the question. For example what router model, firmware version, etc...

There are so many possibilities and I think the crystal halls don't work on network setups...

Geekzone broadband switch | Amazon (Geekzone aff) | MightyApe (Geekzone aff) | Backblaze cloud backup (personal and business) | My technology disclosure

Ragnor

8019 posts

Uber Geek
+1 received by user: 385

Trusted

Subscriber

Reply # 706202 25-Oct-2012 11:59

From your list you can see 192.168.1.101, 192.168.1.103, 192.168.1.105 opening ports, so what's running on those machines?

Likely to be software like utorrent.

colinuu

97 posts

Master Geek
+1 received by user: 4

Reply # 706512 25-Oct-2012 20:49

Ok, more information..

Router is Huawei B970b, connecting on the Vodafone RBI 3G service.

192.168.1.51 is a Windows XP machine, running all the time. It doesn't appear to open any Teredo ports.

The listed IP numbers .100 and above I think relate to two Windows 7 laptops. I have some other devices on the network as well and it's difficult to track the IP numbers over time. Unfortunately this router makes no attempt to reassign the same number to any given machine each time it comes onto the network.

No torrents running during this period (since last reboot of the router). One laptop is doing general web browsing and email, and visits to Geekzone. My wife goes to Facebook a bit on her laptop and plays Bejwelled Blitz online quite a lot.

I know Teredo is a Microsoft service. I never saw it show up in the virtual servers list before on the old ADSL router. I believe it can be turned off, but I don't know how that will affect our internet use. I would like to find out how to stop it from continuing to open new ports all the time, which then remain open forever (that is until the next re-boot).

Cheers,

Ragnor

8019 posts

Uber Geek
+1 received by user: 385

Trusted

Subscriber

Reply # 706540 25-Oct-2012 21:43

Could run Wireshark or Sysinternals TCPView (It shows UDP too) on the Win7 laptops and find out what services/apps are opening those ports.

colinuu

97 posts

Master Geek
+1 received by user: 4

Reply # 707212 26-Oct-2012 22:02

Ragnor: Could run Wireshark or Sysinternals TCPView (It shows UDP too) on the Win7 laptops and find out what services/apps are opening those ports.

Thanks for suggestion. Will have a go with this over the weekend.

The list has now grown by another 5 lines... Am I the only one seeing this?

colinuu

97 posts

Master Geek
+1 received by user: 4

Reply # 708760 29-Oct-2012 21:51

I have now formed the opinion that the Huawei implementation of the UPnP support is faulty. It would seem that when a port is opened with UPnP, the Huawei adds this port to it's virtual servers list where it stays, just the same as a manually added one. Thus the port forward persists forever, even through a power cycle, and so the list grows and grows over time.

I re-configured my network using a D-Link DIR-600 as the UPnP enabled DHCP server. The Huawei now acts pretty much just as a modem, connecting the D-Link WAN port to the internet. The D-Link doesn't expose port forwards through the web interface, so I use a little app called UPnP Wizard to see what;s going on. In here I can see which ports have been opened by Skype, uTorrent etc. Teredo ports appear in the list from time to time, and then disappear, much as I expect is intended. The list no longer increases with time.

So - problem solved. Thanks for the assistance.

Cheers,