Hello,

I read multiple places that the first octate of Class A IP Address is reserved. What does this mean? Who reserved it? One of my local connections has an IP address starting with 0. I do not know how it got there. I just installed a webcam. Is it possible it is an address used by the usb connection of the webcam?

Regards,
btexpress

Whats exact IP address ?

0.1.0.5

Thanks,
btexpress

Thats the strangest IP I have ever seen.

From RFC 790, this adress is reserved (for future used)
As long as you don't need to access it from internet, it should be ok. On internet, this adress might be considered as Martian Address

http://www.webopedia.com/TERM/M/martian_address.html
http://www.ietf.org/rfc/rfc790.txt
http://www.ietf.org/rfc/rfc791.txt

It is not normal. What kind of webcam is this?

the first octect ISNT reserved.. there are afew class a network addresses that are reserved though, like the one given.. but the entire octect isnt reserved.

does the internet happen to be working on this computer?

the webcam wouldnt interfere, unless its hooked up over a network or something.. which still shouldnt screw up YOUR ip address.

Well, for me the RFC is the only standard for IP addresses so it seems the whole range is reserved. If not which one are, which one aren't?

The RFC is the bible. But RFC790 that is referenced above has been obsoleted many times. You could refer to RFC1700, seems to be the latest text based document. But even this has been replaced by RFC3232, which refers to an online database. It's only short, so I'll paste RFC3232 here:

Description

From November 1977 through October 1994, the Internet Assigned
Numbers Authority (IANA) periodically published tables of the
Internet protocol parameter assignments in RFCs entitled, "Assigned
Numbers". The most current of these Assigned Numbers RFCs had
Standard status and carried the designation: STD 2. At this time,
the latest STD 2 is RFC 1700.

Since 1994, this sequence of RFCs have been replaced by an online
database accessible through a web page (currently, www.iana.org).
The purpose of the present RFC is to note this fact and to officially
obsolete RFC 1700, whose status changes to Historic. RFC 1700 is
obsolete, and its values are incomplete and in some cases may be
wrong.

We expect this series to be revived in the future by the new IANA
organization.

Thank you all for your posts. I am still not clear how I was getting this ipaddress. I rebooted my machine and the connection is gone. Could it be some sort of a trojan backdoor? I use an up-to-date firewall and virus protection.

My rule-of-thumb on IP addresses:
192.168.*.* is always private (ie not accessible via internet).
127.0.0.1 is always reserved for localhost interfaces.
Anything else can -as far as I know, but I'm no RFC expert- be allocated to ISPs, via organizations like
IANA.
Simply said, there are some organizations like IANA that distribute the IP address ranges on the internet to ISPs (providers). Those ISPs can then hand out some of the addresses to companies or people.
To get such an IP address (ie an IP usable directly on the internet), you'll need to pay quite some money.
That's why most companies hide the IP addresses from their internal network from the internet and make only a few machines "visible" to the internet (like firewall/router for access, web server for website, mail server for mail traffic, etc).

To get a block or an IP adress you have to contact AfriNIC, APNIC, ARIN or RIPE NCC.
And the problem is not only the cost , the problem is the number (and also the routing table=>CIDR has solved a bit)
4 294 967 296 adresses are available for IPV4.
75% are registered by North America, a lot of which are not used.
When some asiatic countries will arrive, this will be unsufficient. These countries have less than 10% so there will be a problem.
It is here that ipv6 arrives.
Anyway the chinese government is thinking of getting out of internet from what I see in the recent news.. oops I'm getting offtopic