Decks, Patios, Porches and Docks - Sealing a newly bricked porch

I have a brick front porch on a 35 year old brick house. The porch is recessed about 2 feet from the front of the house into the doorway (the block foundation is not recessed) and the brick porch surface (the old thin paver type, about 3/8") leaked water into the basement below the recessed portion of the porch, mainly (I think) because the mortar had cracked over the years. Just today the masons finished a job that included tearing out the old pavers, pouring a new 4" concrete slab, and installing the new type of pavers (about 1-1 1/2" thick) as a surface. They recommend sealing this surface to prevent future leakage. My question is: what type of sealer do I use? Thanks for any help.