dummy ip adresses

[VJ]

Interesting...

So just to see if I get this right...
If I set an IP addres to 192.168.1.100 and a subnet mask 255.255.255.254, there can be another computer physically present on this network with IP 192.168.1.100 and subnet mask 255.255.255.0?

In your example you set 192.69.69.1. Any particular reason for the choice of subnet 192.69?


Jörg

[schmosef]

the netmask defines what part of an ip address represents the network and what part represents the host. with a netmask of 255.255.255.254 there is only room for one host. it's been a long time since i took the microsoft network essentials exam but now that i'm thinking about it i doubt you can have a host value of 0. i think that whatever you choose for the last part of your ip address should resolve to a binary 1 in the right most position. so i think that you need to choose an odd number. (in case i'm not being clear i'm saying that i don't think you can use 100. 101 should be fine.)

with only 1 possible host your pc will immediately try to use the gateway for any network traffic. if you leave the gateway blank your pc will not be able to communicate on any network.

once again, now that i think about it, you may need to leave room in your network for a possible gateway (even if you don't use it) so you may need to use a netmask of 255.255.255.252. in this case you could set your gateway to be x.x.x.1 (x being whatever #s you choose) (don't worry that there's not actually a router at that address; your pc will just assume the network is down). in this case (and if i'm right that a hosts value cannot be 0) you will have to choose an ip for your computer that ends in a binary 10 or 11.

why 69? i like 69!

[VJ]

About that subnetmask: I can see why my PC sees no other computers in the network, but I don't understand why my pc will also be invisible to other computers on the network.

Jörg

[schmosef]

well if you want to play it safe use a really odd ip like 111.111.111.001.

[Pace]

You could use a public IP such as MSN.com's, or perhaps the 169.254.0.0/16 range, subnetting down to one host as described. However, what do you mean by unallowed addresses, and how does your work check for them?

Finally, how much of the NetProfileSwitch functionality do you use? NT command scripts can certainly change IPs - possibly even more (I'll check if you want).

P.