Windows Networking/Subnet masking


What is the generally accepted convention of having all zeros and ones in the extended portion of a home address?

Hi Jacob,

I'm not sure I understand what you are asking, but I'll try to answer.  If you need clarification, send a follow up.

In a subnet mask, if an octet contains all zeros, the computer will be able to communicate with all other computers in that subnet.  For example, if you use, the computer will communicate with any other computer only if the first three octets are the same and the last is different.  If the mask is, then it will communicate with any computer where only the first octet is the same.

In binary, the 255 used in decimal format comes out as "11111111" (eight digits, hence the term 'octet').  When an octet is all ones, that octet is fully masked and a computer will not communicate.

- Mike  

Windows Networking

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Michael Troy


I have a fair amount of experience in peer-to-peer networking. I can answer questions about hardware, networking software, protocol settings, etc. I have some client-server experience, but not a lot with Windows-based servers. I can also give some advice on home network security: VPN, firewalls, anti-virus, etc.


I am the Director of Information Systems for a large law firm which connects about 300 users over five offices via a wide area network. We use client-server, peer-to-peer, remote access, VPN, Internet, and proxy servers.

I also have a peer-to-peer network of computers at home, with file and print sharing, remote access, shared network storage, and shared Internet access with a firewall.

BA George Washington University JD University of Michigan

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