Using the data setup from Eirikur and the data I added, the following works. Not knowing the state of your data, however, I can't promise anything.
CROSS APPLY (SELECT LEFT(sd.IpAddress, PATINDEX('%,%', sd.IpAddress) - 1)) ca1(IP)
CROSS APPLY (SELECT RIGHT(sd.IpAddress, LEN(sd.IpAddress) - PATINDEX('%,%', sd.IpAddress) - 1)) ca2(MAC)
patindex('%,%', sd.IpAddress) > 0;