Unknown port

[DerekK]

Hi all. I'm trying to block access to all ports on a ADSL router (Zyxel). I configured a NAT to non existent addresses at administration ports 80 and 23. Now, when i run an nmap against this IP from a different connection i can see "1755/tcp open wms". Do you know what is this port? I can just do the same (fake NAT) but i'm curious...

[MrLinus]

Windows Media Service. This Link might be of help. (remember, google is your friend)

[DerekK]

Thx MsMittens, i saw this before but i can't understand why this port is opened by default... There are a lot of applications that may need open ports but they aren't configured by default in the routers...

[DerekK]

I was googling deeper and i found some references at proxy that is using the main comm company here in spain (yes they use something they call "transparent proxy"). I did an scanner to the same net than my router and in ALL of them this port appears to be open... it seems that the proxy could be confusing nmap... Do you know something about that?

[MrLinus]

Well, the port may be open on all the other routers if all the other users use Windows (given that the Windows Media player is a common used application). But it could also be a proxy. You'd have to ask your ISP about it and what the proxy is used for. Seems unusual to stick it at port 1755.