Whether you have a static or dynamic IP depends on
your ISP, and whether you want one or not. Some ISPs charge extra for
a static IP address.
A dynamic IP is normally issued from a "pool" of IP addresses
that is within a range owned by your ISP. Each time you log on you
will be allocated an IP address from within the pool. When you log
off the IP address goes back into the pool ready for the next user
to log on.
A static IP address is one that you keep all the time.
There are advantages and disadvantages of both types. Personally
I prefer a static IP and its something that I specifically looked
for when choosing my ISP.
A static IP address allows you to run your own servers (such as mail,
web, ftp) as it means that your IP address will always point to a
One of the advantages for me (aside from the fact that I do run a
server) is that I can log into my home PC from just about anywhere
Some users have concerns about static IP's and think that dynamic
addresses are safer.
Unfortunately this is a misconception, you are just as likely to be
targeted by a wanabee hacker if you are on a dynamic IP. They get
hold of an ISP's range of IP's and scan all IP's within that range
looking for a vulnerable machine.
Put it this way.. When I was with BTInternet I got scanned at least
10 times a day.
Other disadvantages of being on a dynamic IP address are that you
may be unfortunate to be assigned an IP address that some idiot before
you had. And all of a sudden you find yourself being a target of a
DoS attack. (Yep had that happen too). Luckily this can be easily
solved by logging off and logging back on again.
Something else I've found myself target to was being unable to read/post
a forum I frequented. Turned out that someone on my IP range had been
an idiot and the forum owner realising that the other user was on
a dynamic IP.. banned all IP's within that range :/ No amount of logging
on or off would cure that one :(
The other big misconception of a dynamic IP address is that users
think they are safe and unable to be tracked if they carry out such
activities as pr0n or p2p.
- Wrong, the relevant authorities only have to advise your ISP, who
are able to track YOU down in an instant.
So how can you stop your IP address being shown on the likes of forums?
Well unless you use a proxy server you cant really, but to be fair
most forums don't disclose this information and its only available
to mods for control purposes.
One place where it will show up is when using IRC.. this doesn't worry
me too much.. because I have a static IP I can control my rDNS to
a certain extent. If someone really wants to get your IP address then
Every time you make direct contact with another internet user there
is a risk they can get your IP address.
So what can someone do if they have your IP address?
Umm... well they can find out who your ISP is.
If you have been a bad boy on that IP then they can block you, or
even try DoS you...
But guess what.. if they try DoS you.. or scan you... your firewall
will advise you of their IP address and all you have to do is report
them to their ISP, who will act on this information and they may loose
their own internet connection. ;)
It is only your own ISP who has access to your IP address and your
own personal information. Because of the Data Protection Act they
can only disclose this to the relevant authorities such as the police
when requested to do so.
Even using proxy IP's you can be tracked back to your true IP address
if required by the authorities....
(Unless you know how to find and use an open http proxy which has
been badly configured).
I hope I've put to rest some of your fears about "leaving tracks"
with your IP address, unless you are worried about someone finding
out which ISP you are with then as long as your PC is protected by
a firewall and you aren't an idiot online then you don't have anything
to worry about.
If you do abuse then its up to your ISP to take action.
All in all its a good thing (for the sake of our kids etc) that there
are such things in place to protect the innocent.