The PLL problem?

Hello :

I use the megawizard to make a PLL module. But in the PLL module no Td(ns) parameter,I have

see the parameter in the niosII_stratix_1s10_ES\full_featured.bdf .The sdram'clock have the Td parameter.

So I want to ask that the Ph and the Td are the same? I think two parameter shoule be same ,both to

make the clock from fpga to sdram delay or predict.