i have never seen the ip address 192.168.1.0 used. why is that?

Question

What would use this type of ip address?

I realize that addresses such a 10.xxx.xxx.xxx and 192.xxx.xxx.xxx are not redirectable and thus are not used by the "internet" but can be used by LANs. I have a friend who is running norton firewall and a message pops up identifying this ip address. it happens randomly.

It is the ZERO in the last field I am inquiring about. I have NEVER seen a router using a ZERO in ther last field (only a 1). I have seen routers only use 0 and 1 in the 2nd to last field

Answer 1

An IP address is divided into two parts, the "network" part and the "local" part. Each of the four numbers in an IP address can range from 0 to 255 (in geek it is an 8 bit number), and there are various rules for what values the numbers can have. In the "normal" case (in geek the 192.168/16 networks subnetted as /24), the first three numbers (192.168.1) are the network part. All machines with the same network part can talk to each other without needing a router between them. This is the case for most home networks--all the machines will have the same first 3 numbers (in geek that's only for /24 Class C nets, with a netmask of 255.255.255.0, but I digress...)

Then the final number (must range from 1 to 254) is the local part, which identifies a particular computer, or "host". The host numbers "0" and "255" are reserved (you'll see why below) and may not be used as a local part to identify a host.

When talking from one host to another, if the final number is "255" or "0, it means "broadcast this to ALL the hosts with the same network part". Thus "0" and "255" mean "ALL hosts", which is why it is reserved for identifying a PARTICULAR host. (Yes, technically "0" is reserved and "255" is the broadcast address, but for historical reasons using "0" works just fine for broadcast)

Fun tip: If you "ping" 192.168.1.255 (or 192.168.1.0), then ALL the hosts on the network will respond (due to 0 and 255 being the "broadcast" address, so all the hosts see the ping request and will respond). Some versions of ping require a "-b" option to send to the broadcast address. This is a quick and dirty way to see what hosts are out there on a network. You can also ping "255.255.255.255" which is the universal broadcast address (all networks, all hosts).

BTW, routers don't (as a norm) forward packets sent to the broadcast addresses, so trying the broadcast "ping" to a network with a different network part than the machine doing the pinging won't work. If it did, you could get a response from every host on the internet!

Answer 2

192.168.x.x is a class C IP addy. It's mean for local networks. For example you have 5 machines in a network at home but you have a router that talks to your broadband. Your router has an external IP of something like 224.x.x.x while all your machines on the inside of the router use 192.168.x.x To machines on the other side of your router all your machines appear to be a single machine with a single IP addy. Inside the router they are all split into your local lan with seperate IP addys.

You won't see that used on external networks because that particuler IP addy is reserved for local lans. You can have only 254 machines per lan is one of the big restrictions. I suspect many routers won't even address an external local lan IP and will treat it as a bridge between local lans instead. I'm curious now and will have to try that sometime :)

Answer 3

Some IP addresses are for "private" use so that you as a home user or even an entire company can use their own IP addressing scheme, regardless of what the outside world uses. This way, all of us can have 192.168.1.0 networks in our homes and there are no conflicts. These addresses are not routable on the Internet, and your home router does something called NAT (Network Address Translation) for convert the 192.168 number to the addresses used by your service provider which IS globally routable. This private address space is governed by the Internet RFC 1918. It allows for the use of 10.0.0.0 and 172.16.0.0 through 172.31.0.0 networks, as well as for 192.168.0.0 networks.

Answer 4

The 0 cannot be used since it stands for the address of the network itself. On a class C network (256 ip addresses) you have:

xxx.xxx.xxx.0 -> Network address
xxx.xxx.xxx.255 -> Broadcast address (all IP addresses in use respond to this special address)

But consider that network and broadcast addresses do not have necessarly to be 0 and 255! It depends on the network mask in use.

More information here:

http://computer.howstuffworks.com/question549.htm

Answer 5

That IP address is used by linksys (cisco) for home networking. So it wouldn't be a valid address for any website.

Plus ip addresses are assigned to various companies around the globe or for home networking. So an IP address can only belong to one company and others cannot use it. This subnet was specifically assigned to home networking.

Answer 6

It is a local private address used behind routers. This address is not actually use on the Internet.

Answer 7

The entire "192.168.x.x" IP address range is reserved for private networks, as is "192.168.1.0". Routing devices are supposed to take "192.168.x.1", so they don't assign "192.168.1.0" to avoid confusion.

Answer 8

it's of the default addresses for a broadband modem. at &t uses 192.168.0.1 you type it into the address bar in internet explorier to access the modem options.

Answer 9

coz its never used

Answer 10

I have it!