Role of Swap Counterparty in NHA MBS Market

Hello,

I work at a central banking facility and we are considering getting into the Canadian mortgage securitization market as a Servicer. One thing I can’t seem to find much info on is the role of the swap counterparty.

I understand that the swap counterparty enters into swap agreements with either CMHC (IMPP program) or CHT (CMB program) but is the issuer required to enter into swap agreements with a counterparty? If there’s any betterer explanation or sources you have, I greatly appreciate it.

Thanks