# Report Offensive Message

###### I can assure you the math is on my side
Yes, a 4-digit base-256 number written with base-10 symbols and separated by periods. A 12 digit base-10 number would actually be 999.999.999.999 and last time I checked there is no such IP address. Even if we used Hex symbols like FF.FF.FF.FF (which is a valid way to write an IP address) to represent an IP address it would STILL be a 4-digit base-256.

The reason we use base-10 or base-16 symbols to represent a base-256 number is because no official symbols exist for base-256. But let's say that the symbol (+) had been chosen to represent the highest number in a base-256 system, then the largest IP address number would be (+).(+).(+).(+)

But all this is just arbitrary on how we use the period separator. An IP address could just as easily use 7 period separators for an 8-digit HEX number instead so the biggest IP address would look like "F.F.F.F.F.F.F.F". But instead we're using 3 separators making it "FF.FF.FF.FF" which makes it a 4-digit base-256 number.

If we were truly using a decimal system then IP addresses would run from 0 to 4294967296 though that would be extremely confusing.

I've personally have had programmers thank me that I'm the first to give the proper explaination that an IP address is a 4-digit base-256 number (written with base-10 symbols) and NOT a 12-digit base-10 number which would actually result in a maximum IP address of 999.999.999.999. This programmer never figured out why IP addresses stop at 255.255.255.255 and it finally made sense when I called it a base-256 number.

"It scares me that you're teaching other people subnetting :/"

You should to be careful about putting other people down when you clearly don't understand the math. I take a lot of pride in this particular article because it's used to teach IP subnetting in schools.

"If it was base 256 it would have two possible values, 0 and 1, 0 being 0 and 1 being 256."

YIKES!
Base-2 has 2 possible values from 0 to 1.
Base-10 has 10 possible values from 0 to 9.
Base-16 has 16 possible values from 0 to F.
Base-256 has 256 possible values from 0 to 255.

The reason I say 0 to 255 because there were no symbols created beyond base-16 so we're forced to use base-10 symbols to represent it.
Posted by georgeou
Updated - 18th Jan 2007