The Internet Engineering Task Force (IETF) was faced with competing proposals from Microsoft and Cisco Systems for a protocol specification that would secure the transmission of IPdatagrams through uncontrolled and untrusted network domains. Microsoft's proposal was an attempt to standardize the Point-to-Point Tunneling Protocol (PPTP), which it had championed. Cisco, too, had a protocol designed to perform a similar function. The IETF combined the best elements of each proposal and specified the open standard L2TP.