given an ip address and just "www.xyz.com"...

how can (browser) people find out all my sub-domain e.g.

http://abc.xyz.com
http://function1.xyz.com
http://function2.xyz.com given an ip address or just
http://www.xyz.com ?????


....etc.



Jenny.

>> how can (browser) people find out all my sub-domain e.g

Tell them the URLs or post a link to those subdomain sites.

I am not sure if I understand your question correctly. Are you trying to create subdomains for your existing site of http://www.xyz.com? It would be helpful if you tell us your real domain (no example please).

their competitors.

I do not understand this why competitor of my isp scan ( sniffer many of my ports) on early morning at about 3:00 o'clock a few days ago when I do not have my dns server point to out portal.

I did not know what they did, but I have their ip address and I used neotrace back them after I have recorded by ip, port, date, time....etc.

I knew what prefix of my isp and before I deny from the whole block.

sorry I may be a little across post here since I donot any security discuss site.
I have built the virtual domain ( sub-domain ) a few months ago.

my actual question is, can people know your subdomain ( not through hacking / hacking tools)



Jenny.

>> can people know your subdomain ( not through hacking / hacking tools)

No unless your DNS server is misconfigured to allow zone transfer to everyone who requests it, then he/she can see all the available subdomains for your xyz.com zone record. Even if you have wildcard enabled on xyz.com, people still have to guesstimate what subdomains available.
BTW, is it a top secret to hide the name of your subdomains?

both my isp and his competitor scan ( sniffer my ports) and I can tell from router report.

No, it is not top secret at all. But I block my isp to see out web page via deny from 200-210.x.y.z. x.y.z are not filled.

I know they can used some technique called IP spoofing so that
they see our portal with an ip other than above such as

55.44.33.22.11. Am I right about ip spoofing???

I have many jargons that I do not understand since they are written in english.


jenny.