Originally Posted by mrvideo
IP address, like phone numbers, have to be fake, otherwise there are those of us who will try to go to the IP address, or call the phone number. Unlike the 555 exchange for phone numbers there isn't anything like that for any IP address.
Actually, there are.
For IPv4, there are 192.0.2.0/24, 198.51.100.0/24, and 203.0.113.0/24 blocks reserved for "TEST-NET-1", "TEST-NET-2" and "TEST-NET-3" respectively for documentation purposes in RFC 5737, never assigned to an organization, and may be filtered, both locally and publicly, and actually operators are encouraged to filter (i.e., block) them.
Likewise, for IPv6, 2001:db8::/32 is a block reserved for documentation and should also be non-routeable, or at least never assigned, according to RFC 3849, and again operators are encouraged to filter (block) them.
Obviously, these ranges are not as well known as the 555 exchanges.
But, yes, the writers of CSI: Cyber chose instead to use IPv4 octets > 255 or non-numeric characters to come up with obviously invalid IPv4 addresses.