Im quite new to the net so bare with me...
First of all, here are my details: Win. XP pro. (with QoS Packet Scheduler, Network Monitor Driver and ofcourse TCP/IP enabled), adsl with dynamic ip, Topcom Xplorer 871BT modem/router, sygate personal firewall(XP firewall disabled).
Recently i installed an ftp server(Cerberus - the last version). i did port forwarding on the router, and it all works ok, connecting from the net and downloading goes fine. A few days ago i was playing around with portscanners(Advanced Port Scanner and Languard Scanner). ive scanned all 3 ip addresses(wan,lan and my comp.) The results were as follows: wan ip - 23 and 80 open. lan ip - 21, 23 and 80 open. my comp. ip - 135, 139, 1025 and 1550 open.
Dont have to say i was quite surprised to see port 23 open when scanning my wan ip. i then tried telnetting to my wan ip and succeeded. i asked a friend of mine to do the same from the outside, and he didnt get the login prompt(only something about "no success connecting" or something similar).
So, my questions are: since i didnt do any configuring on the router except for forwarding port 21, why is that port open? why did i connect to it through telnet, while my friend didnt? ofcourse i changed the password immediately, but is this in any way a security hole? ive searched throughout the configuration menu on my router but i didnt see anything about port 23 being open(neither port 80 for that matter). is it open by default, and how do i disable it?
i also dont understand why port 21 for ftp didnt pop up as an open port when i scanned my wan. how can anyone ftp to me if that port isnt open "from the outside"(ie. from the "wan ip side") of the router? why is port 80 open if i dont have a web server installed, and hence no service to listen on that port?
i also did a port scan on a friend of mine, and all ports were closed, yet he has absolutely no problems viewing web pages, downloading etc. how is that possible? and 1 more question. is port scanning a legal activity? does my isp monitor that in any way?
i suppose all these questions mean im missing on something VERY basic as far as ips, routers and ports are concerned. ive tried googling but havent found any real answers. anyone knows of any good tutorials out there?
any answeres will be really appreciated...
First of all, here are my details: Win. XP pro. (with QoS Packet Scheduler, Network Monitor Driver and ofcourse TCP/IP enabled), adsl with dynamic ip, Topcom Xplorer 871BT modem/router, sygate personal firewall(XP firewall disabled).
Recently i installed an ftp server(Cerberus - the last version). i did port forwarding on the router, and it all works ok, connecting from the net and downloading goes fine. A few days ago i was playing around with portscanners(Advanced Port Scanner and Languard Scanner). ive scanned all 3 ip addresses(wan,lan and my comp.) The results were as follows: wan ip - 23 and 80 open. lan ip - 21, 23 and 80 open. my comp. ip - 135, 139, 1025 and 1550 open.
Dont have to say i was quite surprised to see port 23 open when scanning my wan ip. i then tried telnetting to my wan ip and succeeded. i asked a friend of mine to do the same from the outside, and he didnt get the login prompt(only something about "no success connecting" or something similar).
So, my questions are: since i didnt do any configuring on the router except for forwarding port 21, why is that port open? why did i connect to it through telnet, while my friend didnt? ofcourse i changed the password immediately, but is this in any way a security hole? ive searched throughout the configuration menu on my router but i didnt see anything about port 23 being open(neither port 80 for that matter). is it open by default, and how do i disable it?
i also dont understand why port 21 for ftp didnt pop up as an open port when i scanned my wan. how can anyone ftp to me if that port isnt open "from the outside"(ie. from the "wan ip side") of the router? why is port 80 open if i dont have a web server installed, and hence no service to listen on that port?
i also did a port scan on a friend of mine, and all ports were closed, yet he has absolutely no problems viewing web pages, downloading etc. how is that possible? and 1 more question. is port scanning a legal activity? does my isp monitor that in any way?
i suppose all these questions mean im missing on something VERY basic as far as ips, routers and ports are concerned. ive tried googling but havent found any real answers. anyone knows of any good tutorials out there?
any answeres will be really appreciated...
