Nmap questions concering my router

Hello i have a Speedtouch 530 modem/router. i use WinXP(Gentoo too :-)

when i namp from console i get this:

D:\nmap>nmap -sT -sV -O -P0 dslcustomer-225-52.vivodi.gr

PORT STATE SERVICE VERSION
21/tcp open ftp Alcatel Speedtouch aDSL router ftpd
23/tcp open telnet SpeedTouch DSL router admin interface
137/tcp closed netbios-ns
138/tcp closed netbios-dgm
139/tcp closed netbios-ssn
445/tcp closed microsoft-ds
1723/tcp open pptp?
Too many fingerprints match this host to give specific OS details

Well i port scan my friend computer which he uses the same isp and same
exact router i dotn see the same results:

D:\nmap>nmap -sT -sV -O -P0 dslcustomer-222-75.vivodi.gr

(The 1659 ports scanned but not shown below are in state: filtered)
PORT STATE SERVICE VERSION
137/tcp closed netbios-ns
138/tcp closed netbios-dgm
139/tcp closed netbios-ssn
445/tcp closed microsoft-ds
Too many fingerprints match this host to give specific OS details

Nmap finished: 1 IP address (1 host up) scanned in 281.141 seconds

a) why to me it reports i have 21, 23 and 1723 port open? i didnt open
them btw. ISP did this?
Is this because my ISP wants to remote managing me?
For example to upload his own firmware?
Why 3 ports and whats he is doing with every 3 of them?

b) Why doesnt report the smae from my friends pc when i nmap him?
Is this because iam issuing the command behind my router, but if so
whats the problem with that?

c) why the netbios ports are displayed if they are closed? other ports
as closed as well but nmap doesnt display them. why for netbios it does?

d) I am also running an http server Apache v2.0.55 (win32) and a smpt
server and have 4899 port open but it doesnt show up why?

e) Is nmap a really good port scanner or there is soemthign better?

Thank you.
Received on Thu Sep 29 19:59:50 2005