IP Address Converter

Question

There is IP address: 66.102.13.19, and from this address as that received this address

http://1113984275

But how? And how I can make this with the help of bash. For example, this service can do it, but I do not understand the algorithm.

Answer 1

IP address -> Number:

echo 66.102.13.19 | tr . '\n' | awk '{s = s*256 + $1} END{print s}'

Number -> IP address:

(export ip=1113984275; for i in {1..4}; do s='.'$((ip%256))$s && ((ip>>=8)); done; echo ${s:1})