1. A system for supporting virtual machine live migration in a network, comprising: a first host and a second host each comprising one or more microprocessors; a virtual switch associated with a plurality of virtual functions (VFs) wherein each said virtual function (VF) is associated with a separate queue pair space; and wherein said virtual switch is configured to attach a said virtual function (VF) to a virtual Host Channel Adapter (vHCA) attached to a virtual machine (VM) on said first host, wherein said virtual function (VF) is associated with a virtual interface (VI) comprising a queue pair (QP) in said queue pair space which provides for communication of messages between said virtual machine and a destination, and wherein said vHCA is assigned a local identifier (LID) and wherein said QP uses said LID as a communication attribute, and support migrating said virtual machine and attached vHCA from said first host to said second host, wherein said virtual function remains attached to said vHCA attached to said virtual machine after migration and wherein said vHCA continues to use said assigned LID after migration such that said queue pair (QP) which uses said LID as a communication attribute continues to provide for communication of messages between said virtual machine and said destination after migration.