Hi everyone,
I need to pick the brains of several network specialists. If you know TCP/IP like the back of your hand, please read this and see if you can help me.
A machine somewhere doesn't seem to connect to the LAN. It has a subnet mask of 255.255.204.0
Straight away, I noticed the address was subnetted, so I started working it out and it didn't make sense.
The third octet of the subnet mask concerns me. On the third octet, if you were to borrow 2 bits off the host portion (all bits set to 0) to create subnetworks, you'd end up with a subnet mask of 255.255.192.0. If you were to borrow 3 bits off the host portion, you'd end up with a subnet mask of 255.255.224.0.
So, it looked like a typo to me. They meant to put 224, not 204.
The person who set this up confirmed that this was correct but it doesn't make sense to me. You can't have a bit set to 1 after a bit set to 0 in an octet for a subnet mask, so where does the 224 come from? It should either be 192 or 224.
Am I correct or am I missing something critical here?
Cheers,
Cicine
I need to pick the brains of several network specialists. If you know TCP/IP like the back of your hand, please read this and see if you can help me.
A machine somewhere doesn't seem to connect to the LAN. It has a subnet mask of 255.255.204.0
Straight away, I noticed the address was subnetted, so I started working it out and it didn't make sense.
The third octet of the subnet mask concerns me. On the third octet, if you were to borrow 2 bits off the host portion (all bits set to 0) to create subnetworks, you'd end up with a subnet mask of 255.255.192.0. If you were to borrow 3 bits off the host portion, you'd end up with a subnet mask of 255.255.224.0.
So, it looked like a typo to me. They meant to put 224, not 204.
The person who set this up confirmed that this was correct but it doesn't make sense to me. You can't have a bit set to 1 after a bit set to 0 in an octet for a subnet mask, so where does the 224 come from? It should either be 192 or 224.
Am I correct or am I missing something critical here?
Cheers,
Cicine