What do you mean by using UNIX in a DOS window? Are you connecting to a shell with ssh or something like that?
I'm not sure I understand your example. You want to type in A12.1.13.15 and have it come out as aaaaBbbbCccc? Try
Code:
$ alias A12.1.13.15="echo 'Hello there'"
$ A12.1.13.15
Hello there
$
