Modeling ipaddresses


Bare with me as I outline the set up. I have a db table with the schema

id int(10) unsigned
ipaddr int(32) unsigned
maskbits int(8) unsigned

and a web form where the use enters the ip address and mask. The
controller and view are easy enough. The model on the other hand is
causing problems. As the ip address is entered in the form as
“ddd.ddd.ddd.ddd” with a netmask between 0 and 32. This is stored as an
integer so as to be able to use sql to do netmask operations, I need to
typecast between the two in the model. I found the composed_of
directive, but am scratching my head when it comes to applying this to
the IPAddr class. It is beginning to look as if I’ll have to
re-implement the IPAddr class as a value object unless someone cares to
give me a few pointers. Is there an esay way to do what I wish to do?