A virtual infrastructure, comprising: a plurality of hosts (110, 114) each having a virtual machine executing therein and a virtual switch in a virtual network; and a virtual machine management server, VMMS, characterised in that the VMMS is configured to: receive a service definition from a network service offered for a physical network, the service definition including information about the network service and configuration instructions for configuring a host of the plurality of hosts (110, 114) to use the network service; create one or more service profiles for the network service based on the service definition of the network service, each of the one or more service profiles including the information about the network service and the configuration instructions, and including parameters of the network service for use on a virtual machine of said plurality of virtual machines; register the network service by adding the one or more service profiles to a directory of network services, the directory indicating whether the service profile is available to the virtual machines; and in response to receiving a selection of the service profile from the directory and a selection of one of the virtual machines, enable the network service for the selected virtual machine by using the configuration instructions to configure the virtual switch of the host of the selected virtual machine with rules and/or filters that forward packets from the selected virtual machine to the network service of the selected service profile. a plurality of hosts (110, 114) each having a virtual machine executing therein and a virtual switch in a virtual network; and a virtual machine management server, VMMS, characterised in that the VMMS is configured to: receive a service definition from a network service offered for a physical network, the service definition including information about the network service and configuration instructions for configuring a host of the plurality of hosts (110, 114) to use the network service; create one or more service profiles for the network service based on the service definition of the network service, each of the one or more service profiles including the information about the network service and the configuration instructions, and including parameters of the network service for use on a virtual machine of said plurality of virtual machines; register the network service by adding the one or more service profiles to a directory of network services, the directory indicating whether the service profile is available to the virtual machines; and in response to receiving a selection of the service profile from the directory and a selection of one of the virtual machines, enable the network service for the selected virtual machine by using the configuration instructions to configure the virtual switch of the host of the selected virtual machine with rules and/or filters that forward packets from the selected virtual machine to the network service of the selected service profile. receive a service definition from a network service offered for a physical network, the service definition including information about the network service and configuration instructions for configuring a host of the plurality of hosts (110, 114) to use the network service; create one or more service profiles for the network service based on the service definition of the network service, each of the one or more service profiles including the information about the network service and the configuration instructions, and including parameters of the network service for use on a virtual machine of said plurality of virtual machines; register the network service by adding the one or more service profiles to a directory of network services, the directory indicating whether the service profile is available to the virtual machines; and in response to receiving a selection of the service profile from the directory and a selection of one of the virtual machines, enable the network service for the selected virtual machine by using the configuration instructions to configure the virtual switch of the host of the selected virtual machine with rules and/or filters that forward packets from the selected virtual machine to the network service of the selected service profile.