Point to Point Tunneling Protocol点对点隧道协议 Point-to-Point Tunneling Protocol点对点信道通讯协议 Preproduction Test Procedure生产前试验的程序 Program Performance Test Procedure程序的性能测试程序 Program Performance Test Plan程序的性能测试计划 γ-phenylpropyltriphosphate Pigeon Packet Transfer Protocol鸽子封包传输协议