The Point-to-Point Protocol (PPP) provides a standard method for the transport of multi-protocol datagrams over point-to-point links. PPPoA refers to Point-to-Point Protocol over Asynchronous Transfer Mode (PPPoA).
The PIX Firewall does not support the PPPoA configuration because PPPoA uses encapsulation over ATM, and the PIX cannot interpret ATM frames.
The PIX does support the configuration of PPP over Ethernet (PPPoE). For more information on the configuration of PPPoE on the PIX, refer to these TAC Case Collection (TAC CC) cases: