best way to split by "," and interate?

[Jorge Pereira]

Hi,

    I have a list

update control {
    &Tmp-String-0 = "aa:bb:cc:dd:ee:ff,00:11:22:33:44:55,ff:ee:dd:cc:bb:aa"
}

And I would like to know about the best approach to split by "," and check
if match with my ${Called-Station-Id}
someone have a idea?

--
Jorge Pereira