Hydrolyzes cerebroside sulfate. H2O + N-acyl-1-beta-D-(3-O-sulfo)-galactosyl-sphing-4-enine = a beta-D-galactosyl-(1<->1')-N-acylsphing-4-enine + H(+) + sulfate Binds 1 Ca(2+) ion per subunit. Homodimer at neutral pH and homooctamer at acidic pH. Exists both as a single chain of 58 kDa (component A) or as a chain of 50 kDa (component B) linked by disulfide bond(s) to a 7 kDa chain (component C). Interacts with SUMF1 (By similarity). The conversion to 3-oxoalanine (also known as C-formylglycine, FGly), of a serine or cysteine residue in prokaryotes and of a cysteine residue in eukaryotes, is critical for catalytic activity. This post-translational modification is severely defective in multiple sulfatase deficiency (MSD). Belongs to the sulfatase family.