Custom Field Pairs

Is there a way to create custom fields that have relationships? What I would
like to do is have an IP address associated with an NT domain like this:

NT1_DOMAIN 10.1.1.1
NT2_DOMAIN 10.2.3.2
WORKGROUP 192.168.4.3

If not, how can I put this in as a feature request?

Thanks,

Scott Carpenter
DCERT Engineer
City Wide Information Technology Security (CWITS)
scott.carpenter@dc.gov