ip adres

[nicomerken]

Hello,
I have a dynamic ip adres, hut hsf takes my 172.19.3.xx adres what is a internal adres.
How do i chanche dath?
greatings Nico

[rejetto]

WHO told you it is an internal address?
i think it is not

[jack_2000]

no way ...   172.*  is not an internal ip adres

[MarkV]

From http://www.auditmypc.com/internal-ip.html

Private IP addresses range from:
10.0.0.0 - 10.255.255.255 (CLASS A - 255.0.0.0)
172.16.0.0 - 172.31.255.255 (CLASS B - 255.255.0.0)
192.168.0.0 - 192.168.255.255 (CLASS C - 255.255.255.0)

Additionally, Windows assigns the 169.254.*.* range (APIPA).

All other IPs are public.

nicomerken's IP address falls into the Class B range and is therefore private.

MarkV

[rejetto]

you are right
but not only
there are many other special address
i found many in a text file shipped with emule (i uploaded it to http://www.sendspace.com/file/97blo6 for reference)

now, consider the address in the form a.b.c.d
the new code for detecting internal addresses is the following

(a in [0,1,2,5,10,23,27,31,36,37,39,41,42,46,49,50,58..60,71..79,89..127,173..187,189,190,197,223,224..255])
or (a = 192) and ((b in [0,168]) or (b = 68) and (c = 185))
or (a = 191) and (b = 255)
or (a = 169) and (b = 254)
or (a = 172) and (b in [16..31])


do you find anything wrong in it?

[MarkV]

I took a look here rejetto, and it seems altough there are many special IPs only the three I mentioned are actually reserved for private purposes. All other "Reserved" may change in the future.

The link above is the RFC1918, it's the reference one should follow I think...

I quote excerpt:

3. Private Address Space

   The Internet Assigned Numbers Authority (IANA) has reserved the
   following three blocks of the IP address space for private internets:

     10.0.0.0        -   10.255.255.255  (10/8 prefix)
     172.16.0.0      -   172.31.255.255  (172.16/12 prefix)
     192.168.0.0     -   192.168.255.255 (192.168/16 prefix)

   We will refer to the first block as "24-bit block", the second as
   "20-bit block", and to the third as "16-bit" block. Note that (in
   pre-CIDR notation) the first block is nothing but a single class A
   network number, while the second block is a set of 16 contiguous
   class B network numbers, and third block is a set of 256 contiguous
   class C network numbers.

I found no error in your formula, but I don't know what these "special" reserved IPs are for. What I know is that if your server is hit by one of the three ranges above + the APIPA one, it is definately a local address (including 127.0.0.1 aka localhost). But I'm no expert.

Edit: found another link

MarkV

[rejetto]

i think you are right
i changed the formula to this

(a in [0,10,23,127])
or (a = 192) and ((b = 168) or (b = 0) and (c = 2))
or (a = 169) and (b = 254)
or (a = 172) and (b in [16..31])

[MarkV]

(a in [0,10,23,127])

Following your document, a=23 is IANA Reserved. I think it's not private though.

I fully agree with the rest of the formula. That should work.

MarkV

[rejetto]

it is currently used by the second biggest phone company in italy for its private network.
here it is actually used as private address.
a lot of HFS users are in such lan, me included

[MarkV]

As I already mentioned

But I'm no expert.

:roll:

MarkV

[jack_2000]

A good idea will be to alert the user if their own ip is 169.254.*.* as it has happened on a number of occasions when my isp's servers fail windows will assign an ip automatically from that range.

[rejetto]

what kind of alert?
only sometimes 169 means the network is not working, other times it is ok.

[MarkV]

169.254.*.* is APIPA, automatically assigned by Windows if the DHCP distribution of an IP address fails. You can't access the net with this IP.

[rejetto]

can you suggest how HFS should behave?

[MarkV]

Good question. HFS doesn't know how the user intends to use HFS. There had to be different modes, similar to easy and expert, but dealing with online status.

offline      - HFS is offline and does not serve (already implemented)
LAN mode - intended for use in a local environment, all options regarding external IPs etc. are hidden and online warnings suppressed.
online      - selected by the user if HFS shall be reachable by external users (Internet). All options are shown and the user will be alerted about possible problems (no external IP detected, DynDNS errors etc.)
A list of options that could be hidden/disabled in LAN mode:
-Self test
-Find external address on startup
-Find external address
-Constantly search for better address
-Dynamic DNS updater