A method for deploying virtual machine instances used to provide services in a service chain in a network functions virtualisation architecture, comprising: obtaining communication relationships between value-added server, VAS, instances and service switch, SSW, instances from a service template, wherein the service template is a network service description, NSD, and/or a virtual network function description, VNFD, of a software defined network, SDN, wherein the SSW instances are configured to provide a function of forwarding a service flow according to a flow table, and a basic L2 switching capability, and support network deployment across three layers by means of a channel such as virtual extensible local area network, VxLAN, wherein the VAS instances and the SSW instances are used to provide services in a service chain, wherein the service chain is a sequence of services that a particular service flow needs to pass through, wherein the service chain and the communication relationships between the VAS instances and the SSW instances are defined in the service template, and wherein said communication relationships between the VAS instances and the SSW instances specifically are: a packet that requires service processing first arrives at the SSW instance, the SSW instance forwards the packet to a corresponding VAS instance for processing, and after completing processing, the VAS returns the packet back to the SSW instance; and deploying, according to the communication relationships, an SSW instance and a VAS instance that need to communicate with each other in the SSW instances and the VAS instances on a same physical machine. obtaining communication relationships between value-added server, VAS, instances and service switch, SSW, instances from a service template, wherein the service template is a network service description, NSD, and/or a virtual network function description, VNFD, of a software defined network, SDN, wherein the SSW instances are configured to provide a function of forwarding a service flow according to a flow table, and a basic L2 switching capability, and support network deployment across three layers by means of a channel such as virtual extensible local area network, VxLAN, wherein the VAS instances and the SSW instances are used to provide services in a service chain, wherein the service chain is a sequence of services that a particular service flow needs to pass through, wherein the service chain and the communication relationships between the VAS instances and the SSW instances are defined in the service template, and wherein said communication relationships between the VAS instances and the SSW instances specifically are: a packet that requires service processing first arrives at the SSW instance, the SSW instance forwards the packet to a corresponding VAS instance for processing, and after completing processing, the VAS returns the packet back to the SSW instance; and wherein the service template is a network service description, NSD, and/or a virtual network function description, VNFD, of a software defined network, SDN, wherein the SSW instances are configured to provide a function of forwarding a service flow according to a flow table, and a basic L2 switching capability, and support network deployment across three layers by means of a channel such as virtual extensible local area network, VxLAN, wherein the VAS instances and the SSW instances are used to provide services in a service chain, wherein the service chain is a sequence of services that a particular service flow needs to pass through, wherein the service chain and the communication relationships between the VAS instances and the SSW instances are defined in the service template, and wherein said communication relationships between the VAS instances and the SSW instances specifically are: a packet that requires service processing first arrives at the SSW instance, the SSW instance forwards the packet to a corresponding VAS instance for processing, and after completing processing, the VAS returns the packet back to the SSW instance; and deploying, according to the communication relationships, an SSW instance and a VAS instance that need to communicate with each other in the SSW instances and the VAS instances on a same physical machine.