private OFMessage getRoleReply(int xid, Role role) {
OFVendor vm = (OFVendor)BasicFactory.getInstance()
.getMessage(OFType.VENDOR);
vm.setXid(xid);
vm.setVendor(OFNiciraVendorData.NX_VENDOR_ID);
OFRoleReplyVendorData replyData = new OFRoleReplyVendorData();
replyData.setRole(role.toNxRole());
vm.setVendorData(replyData);
return vm;
}