Method and terminal for acquiring information on service function chain in next-generation mobile communication network

Abstract

Disclosed in the present specification is a method by which a terminal acquires service function chain (SFC) information. The method comprises the steps of: transferring, to a controller, the terminal state information and/or the terminal configuration information; and receiving the SFC information, determined by the controller, by considering the terminal state information and/or the terminal configuration information, wherein the SFC information includes logical path information of a virtualized network function (VNF). The method can also include a step for receiving sub-chain information, determined by the controller, on the basis of the SFC information, or determining the sub-chain information on the basis of the SFC information.

Claims

1. A method by which a terminal acquires service function chain (SFC) information, the method comprising steps of: transferring, to a controller, terminal state information and/or terminal configuration information; and receiving SFC information, determined by the controller, by considering the terminal state information and/or the terminal configuration information, wherein the SFC information includes logical path information of a virtualized network function (VNF), the method also including a step for receiving sub-chain information, determined by the controller, based on the SFC information, or determining the sub-chain information based on the SFC information.

2. The method of claim 1, wherein the VNF includes a VNF that performs a control plane (CP) function and a VNF that performs a user plane (UP) function that are within a network.

3. The method of claim 2, wherein the VNF that performs the CP function is a virtualization of control signal processing and transmission functions of MME (Mobility Management Entity), S-GW (Serving Gateway), and P-GW (Packet Data Network Gateway), and the VNF that performs the UP function is a virtualization of user data processing and transmission functions of S-GW (Serving Gateway) and P-GW (Packet Data Network Gateway).

4. The method of claim 1, wherein the sub-chain information represents a sub-chain between virtualized functions (VF) in the terminal or a sub-chain between other terminals.

5. The method of claim 1, wherein the step for determining the sub-chain information includes steps of: receiving, by the terminal, a sub-chain determination request from the controller; determining a sub-chain based on one or more among the SFC information, information on the terminal and other terminals, and information on virtualized functions (VF) in the terminal; and transmitting information on the determined sub-chain to the controller.

6. The method of claim 1, wherein the received sub-chain information includes information on a sub-chain determined by the controller by considering one or more among the SFC information, information on the terminal and other terminals, and information on virtualized functions (VF) in the terminal.

7. A terminal that acquires service function chain (SFC) information, the terminal comprising: a transceiver that transfers, to a controller, terminal state information and/or terminal configuration information and receives SFC information, determined by the controller, by considering the terminal state information and/or the terminal configuration information, wherein the SFC information includes logical path information of a virtualized network function (VNF), the terminal also including a processor for receiving sub-chain information, determined by the controller, based on the SFC information, or determining the sub-chain information based on the SFC information.

8. The terminal of claim 7, wherein the VNF includes a VNF that performs a control plane (CP) function and a VNF that performs a user plane (UP) function that are within a network.

9. The terminal of claim 8, wherein the VNF that performs the CP function is a virtualization of control signal processing and transmission functions of MME (Mobility Management Entity), S-GW (Serving Gateway), and P-GW (Packet Data Network Gateway), and the VNF that performs the UP function is a virtualization of user data processing and transmission functions of S-GW (Serving Gateway) and P-GW (Packet Data Network Gateway).

10. The terminal of claim 7, wherein the sub-chain information represents a sub-chain between virtualized functions (VF) in the terminal or a sub-chain between other terminals.

11. The terminal of claim 7, wherein the determination of the sub-chain information by the processor includes: receiving a sub-chain determination request from the controller through the transceiver; determining a sub-chain based on one or more among the SFC information, information on the terminal and other terminals, and information on the virtualized functions (VF) in the terminal; and transmitting information on the determined sub-chain to the controller through the transceiver.

12. The terminal of claim 7, wherein the received sub-chain information includes information on a sub-chain determined by the controller by considering one or more among the SFC information, information on the terminal and other terminals, and information on virtualized functions (VF) in the terminal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a structural diagram of an evolved mobile communication network.

(2) FIG. 2 is an exemplary diagram illustrating architectures of a general E-UTRAN and a general EPC.

(3) FIG. 3 is an exemplary diagram illustrating a structure of a radio interface protocol on a control plane between UE and eNodeB.

(4) FIG. 4 is another exemplary diagram illustrating a structure of a radio interface protocol on a user plane between the UE and a base station.

(5) FIG. 5a is a flowchart illustrating a random access process in 3GPP LTE.

(6) FIG. 5b illustrates a connection process in a radio resource control (RRC) layer.

(7) FIG. 6 is an expected structural view of a core network for the next-generation mobile communication;

(8) FIG. 7 shows a conceptual example of network virtualization;

(9) FIG. 8 shows an example of an NFV framework proposed by ETSI NFV ISG;

(10) FIG. 9 is an illustration of a service function chain (SFC) according to virtualization of the next-generation mobile communication;

(11) FIG. 10 shows an example in which a UE is considered/managed when determining a service function chain (SFC) according to one disclosure of the present specification;

(12) FIG. 11 shows an example in which virtual functions (VF) within a UE are considered/managed when determining a service function chain (SFC) according to another disclosure of the present specification;

(13) FIG. 12 shows an example in which a number of UEs are considered/managed when determining a service function chain (SFC) according to yet another disclosure of the present specification;

(14) FIG. 13 shows a process of determining a service function chain (SFC) by taking UE/terminal state information into consideration, in the example shown in FIG. 11;

(15) FIG. 14 shows a process of determining a service function chain (SFC) by taking UE/terminal state information into consideration, in the example shown in FIG. 12; and

(16) FIG. 15 is a block diagram of the components of a UE 100 and network node according to an embodiment of the present invention.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

(17) The presented invention is described in light of UMTS (Universal Mobile Telecommunication System) and the EPC (Evolved Packet Core), but not limited to such communication systems, and may be rather applicable to all communication systems and methods to which the technical spirit of the presented invention may apply.

(18) The technical terms used herein are used to merely describe specific embodiments and should not be construed as limiting the presented invention. Further, the technical terms used herein should be, unless defined otherwise, interpreted as having meanings generally understood by those skilled in the art but not too broadly or too narrowly. Further, the technical terms used herein, which are determined not to exactly represented the spirit of the invention, should be replaced by or understood by such technical terms as being able to be exactly understood by those skilled in the art. Further, the general terms used herein should be interpreted in the context as defined in the dictionary, but not in an excessively narrowed manner.

(19) Furthermore, the expression of the singular number in the specification includes the meaning of the plural number unless the meaning of the singular number is definitely different from that of the plural number in the context. In the following description, the term ‘include’ or ‘have’ may represented the existence of a feature, a number, a step, an operation, a component, a part or the combination thereof described in the specification, and may not exclude the existence or addition of another feature, another number, another step, another operation, another component, another part or the combination thereof.

(20) The terms ‘first’ and ‘second’ are used for the purpose of explanation about various components, and the components are not limited to the terms ‘first’ and ‘second’. The terms ‘first’ and ‘second’ are only used to distinguish one component from another component. For example, a first component may be named as a second component without deviating from the scope of the presented invention.

(21) It will be understood that when an element or layer is referred to as being “connected to” or “coupled to” another element or layer, it can be directly connected or coupled to the other element or layer or intervening elements or layers may be presented. In contrast, when an element is referred to as being “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers presented.

(22) Hereinafter, exemplary embodiments of the presented invention will be described in greater detail with reference to the accompanying drawings. In describing the presented invention, for ease of understanding, the same reference numerals are used to denote the same components throughout the drawings, and repetitive description on the same components will be omitted. Detailed description on well-known arts which are determined to make the gist of the invention unclear will be omitted. The accompanying drawings are provided to merely make the spirit of the invention readily understood, but not should be intended to be limiting of the invention. It should be understood that the spirit of the invention may be expanded to its modifications, replacements or equivalents in addition to what is shown in the drawings.

(23) In the drawings, user equipments (UEs) are shown for example. The UE may also be denoted a terminal or mobile equipment (ME). The UE may be a laptop computer, a mobile phone, a PDA, a smart phone, a multimedia device, or other portable device or may be a stationary device, such as a PC or a car-mounted device.

Definition of Terms

(24) For better understanding, the terms used herein are briefly defined before going to the detailed description of the invention with reference to the accompanying drawings.

(25) An UMTS is an abbreviation of a Universal Mobile Telecommunication System, and it refers to the core network of the 3rd generation mobile communication.

(26) UE/MS is an abbreviation of User Equipment/Mobile Station, and it refers to a terminal device.

(27) An EPS is an abbreviation of an Evolved Packet System, and it refers to a core network supporting a Long Term Evolution (LTE) network and to a network evolved from an UMTS.

(28) A PDN is an abbreviation of a Public Data Network, and it refers to an independent network where a service for providing service is placed.

(29) A PDN-GW is an abbreviation of a Packet Data Network Gateway, and it refers to a network node of an EPS network which performs functions, such as the allocation of a UE IP address, packet screening & filtering, and the collection of charging data.

(30) A Serving gateway (Serving GW) is a network node of an EPS network which performs functions, such as mobility anchor, packet routing, idle mode packet buffering, and triggering an MME to page UE.

(31) A Policy and Charging Rule Function (PCRF): The node of an EPS network which performs a policy decision for dynamically applying QoS and a billing policy that are different for each service flow.

(32) A NodeB is an eNodeB of a UMTS network and installed outdoors. The cell coverage of the NodeB corresponds to a macro cell.

(33) An eNodeB is an eNodeB of an Evolved Packet System (EPS) and is installed outdoors. The cell coverage of the eNodeB corresponds to a macro cell.

(34) An (e)NodeB is a term that denotes a NodeB and an eNodeB.

(35) An MME is an abbreviation of a Mobility Management Entity, and it functions to control each entity within an EPS in order to provide a session and mobility for UE.

(36) A session is a passage for data transmission, and a unit thereof may be a PDN, a bearer, or an IP flow unit. The units may be classified into a unit of the entire target network (i.e., an APN or PDN unit) as defined in 3GPP, a unit (i.e., a bearer unit) classified based on QoS within the entire target network, and a destination IP address unit.

(37) A PDN connection is a connection from UE to a PDN, that is, an association (or connection) between UE represented by an IP address and a PDN represented by an APN. It means a connection between entities (i.e., UE-PDN GW) within a core network so that a session can be formed.

(38) UE context is information about the situation of UE which is used to manage the UE in a network, that is, situation information including an UE ID, mobility (e.g., a current location), and the attributes of a session (e.g., QoS and priority)

(39) NAS (Non-Access-Stratum): A higher stratum of a control plane between a UE and an MME. The NAS supports mobility management, session management, IP address management, etc., between the UE and the network.

(40) PLMN: as an abbreviation of Public Land Mobile Network, means a network identification number of a mobile communication provider. In roaming case of the UE, the PLMN is classified into a home PLMN (HPLMN) and a vistied PLMN (VPLMN).

(41) A virtual machine (VM): a virtual computer generated by the virtualization technology.

(42) A virtual network (VN): a virtual network produced by applying the SDN technology to network devices produced by various manufacturers.

(43) Software defined networking (SDN): a scheme responsible for the control plane of all of network devices in a central controller in order to assign programmability to the network devices.

(44) A service function (SF): a component function responsible for network services and processes a single packet or traffic. A corresponding component denotes only a logical entity according to each function, and an instance for an actual operation is mounted and executed in a software-shared network resource or physical-dedicated equipment. One or more instances may be present with respect to one service function.

(45) A virtual network function (VNF): a virtual network function operated in a virtual machine and has a meaning similar to an SF.

(46) A service function chain (SFC): a logical path indicating that a received packet or traffic will be processed by which service function according to which sequence. A service chain is defined according to a network service policy. Each chain is selected depending on a traffic classification function.

(47) A service function path (SFP): denotes an instance of a logically defined service chain. This is a path along which a network packet and traffic is actually delivered as the results of mapping a logical service chain to a service function instance, a physical service node, etc. on an actual network.

(48) ETSI NFV ISG: an abbreviation of European Telecommunications Standards Institute Network Function Virtualization Industry Specification Group.

(49) Network function virtualization (NFV): a scheme in which a network function implemented in hardware in a conventional technology using virtualization technology in servers for common purposes is operating on a virtual machine

(50) Network function virtualization infrastructure (NFVI): all of types of infrastructure, such as a processor, memory, a network, and a hypervisor present to provide a virtual machine and a virtual network

(51) A network function (NF): denotes equipment responsible for network-related services, for example, an optimizer, a firewall, a network address translator (NAT), and a gateway.

(52) A virtual infrastructure manager (VIM): a management domain that controls and manages the NFVI.

(53) A virtual network function component (VNFC): a network function of a small unit that forms one VNF.

(54) A VNF forwarding graph (VNFFG): the chaining of VNFs configured to provide a general network service. An actual flow passes along a corresponding path. The VNFFG has a meaning similar to the SFC.

(55) <Core Network for Next-Generation Mobile Communication>

(56) Meanwhile, the next-generation mobile communication, so-called 5th-generation mobile communication, is expected to provide data services with a minimum speed of 1 Gbps. Hence, it is expected that mobile communication core networks will have more overload.

(57) Thus, there is an urgent need for the re-design of core networks in the so-called 5th-generation mobile communication.

(58) FIG. 6 is an expected structural view of a core network for the next-generation mobile communication.

(59) As can be seen with reference to FIG. 6, a UE may be connected to a core network over a next-generation RAN (Radio Access Network). The next-generation core network may include a (Control Plane) CP function node and a UP (User Plane) function node. The CP function node is a node that manages UP function nodes and RAN, which sends and receives a control signal. The CP function node performs all or some of the functions of MME of the fourth-generation mobile communication and all or some of the control plane functions of S-GW and P-GW. The UP function node is a type of gateway by which user data is sent and received. The UP function node may perform all or some of the user plane functions of S-GW and P-GW of the fourth-generation mobile communication.

(60) An AF (Application Function) node is an application server that is located within a DN (Data Network).

(61) <Network Virtualization>

(62) Currently, various network functions (NF) such as a core network (e.g., S-GW, MME, and P-GW) and other network entities (e.g., firewall (FW), a load balancer, and an optimizer) are used in network operation.

(63) However, in the next-generation mobile communication, the entities on the core network may be virtualized by a virtual machine (VM).

(64) FIG. 7 shows a conceptual example of network virtualization.

(65) As shown in FIG. 7, entities (e.g., S-GW, MME, and P-GW) on a core network for the fourth-generation mobile communications or entities (e.g., a CP function and UP functions) on a core network for the fifth-generation mobile communication may be virtualized by a virtual machine (VM). Specifically, a virtual machine may be run on a hardware resource pool, which is a set of hardware (HW), to operate virtual S-GW, MME, and P-GW or virtual CP and UP functions.

(66) Moreover, network entities such as a firewall (FW), a load balancer, and an optimizer may be virtualized by the virtual machine.

(67) Such network virtualization is under discussion in various terms, each of which will be described below.

(68) I. Proposal made by IETF

(69) The IETF (Internet Engineering Task Force) has studied SDN (Software Defined Network) and NFV (Network Function Virtualization) and suggested a service function chain (SFC).

(70) To understand the service function chain (SFC), it is necessary to learn a service function SF. The service function (SF) is a component function that constitutes a network, which processes a single packet or traffic. At this time, the corresponding component only refers to a logical entity for each function, and an instance for actual operation is onboarded and executed on a hardware resource shared by software, and one or more instances may exist for a single service function. Therefore, the service function chain (SFC) is an ordered set of service functions (SF) required for a particular service. That is, the service function chain (SFC) is a logical path that indicates which service function (SF) processes a received packet or traffic in which sequence.

(71) Meanwhile, a service node (SN) is an element entity that is connected to the network, where one or more service function instances are onboarded and executed. A service function receives traffic from the network via a corresponding node and sends processed traffic to the network.

(72) II. Proposal made by ETSI NFV ISG

(73) NFV ISG of ETSI (European Telecommunications Standards Institute) proposes a network function virtual (NFV) to provide a flexible and fast network service.

(74) FIG. 8 shows an example of an NFV framework proposed by ETSI NFV ISG.

(75) Referring to FIG. 8, an NFV framework includes a network function virtual infrastructure (NFVI), a VNF domain, and NVF management and orchestration. The NFVI includes various physical hardware resources (e.g., a CPU, storage, and a network) and a virtualization layer for virtualizing the hardware resources. The NFVI includes virtualized hardware resources (that is, a virtual CPU, virtual storage, and a virtual network).

(76) The VNF domain includes a plurality of virtualized network functions (VNF).

(77) <Introduction of Virtualization in Next-Generation Mobile Communication>

(78) In 3GPP-based next-generation mobile communication, so-called fifth-generation mobile communication, a UP function node and CP function node within a core network are expected to be virtualized.

(79) FIG. 9 is an illustration of a service function chain (SFC) according to virtualization of the next-generation mobile communication.

(80) As can be seen with reference to FIG. 9, a service function chain (SFC) in which VNFs are defined in a meaningful sequence may be formed to send data of a user plane UP or send a signal of a control plane CP.

(81) The SFC controller (or SDN controller) 600 shown in the drawing may selectively control each VNF, and check and control each VNF's state and the network state. The SFC controller may determine the meaningful sequence of the service chain, based on each VNF's state and the network state.

(82) <Objective Pursued by the Disclosure of the Present Specification>

(83) In the aforementioned SDN/NFV, a service function chain (SFC) is determined by dynamically taking the state of each service function (SF)/virtualized network functions (VNF) into consideration, in order to carry user plane data. However, the UE (or terminal)'s environment or state was not taken into consideration, even though the UE (or terminal) is an entity that receives service. Particularly, 5G network environments are evolving towards satisfying various service requirements of the UE (or terminal), so there is a need to take the UE (or terminal)'s environment or state into consideration.

(84) Accordingly, an objective of the disclosure of the present specification is to propose a method of determining a service function chain (SFC) by taking the UE (or terminal)'s environment or state into consideration.

Disclosure of the Present Specification

(85) According to the disclosure of the present specification, there is provided a method that manages and controls a UE (or terminal) in the same manner as VNF when determining a service function chain (SFC).

(86) FIG. 10 shows an example in which a UE is considered/managed when determining a service function chain (SFC) according to one disclosure of the present specification.

(87) Referring to FIG. 10, unlike FIG. 9, a UE 100 and an SFC controller 600 are connected by a dotted line. The dotted line indicates that the SFC controller 600 considers and manages the UE (or terminal) 100 when determining a service function chain (SFC). By considering the UE (or terminal) 100, efficiency can be achieved in the following examples.

(88) For instance, let's assume a scenario where a user with a UE gets on a train or the UE is mounted within the train. In this case, the UE has information on instantaneous speed and directionality. Such information may serve as important information when determining the location of a mobile anchor or whether to reselect the mobile anchor or not. Accordingly, the SFC controller will take the aforementioned information of the UE (or terminal) into consideration when determining a service function chain (SFC).

(89) In another example, configuration information of a single UE may vary depending on the possibility of cooperative communication with a number of sensors around the UE or other terminals. In an e-health scenario, monitors, sensors, etc. capable of direct/indirect communication (e.g., D2D (device-to-device) communication) with neighboring UEs may depend on whether the UE is at home or in a hospital. Thus, the UE may provide the SFC controller with configuration information on its surroundings in a particular environment at a particular time, and the SFC controller may determine which codec is suitable for each UE's monitor and sensor or whether to employ a security module or not, when determining a service function chain (SFC).

(90) As another example of cooperative communication between UEs, an e-class scenario for an educational institution such as a school may be taken into consideration. The performance, screen size, etc. of a teacher's monitor and device may be different from the performances, screen sizes, etc. of students' UEs. Accordingly, configuration information on the surroundings may be provided to the controller under an environment premised on dynamical interactions between UEs, and the SFC controller may determine a proper service function chain (SFC). Particularly, as long as a security scheme based on biological information such as fingerprints, iris scans, etc. is used, the SFC controller may determine a codec suitable for each sensor and determine whether to employ a security module or not.

(91) As yet another example of cooperative communication, a V2X scenario for cooperation between a number of sensors and a UE within a vehicle may be taken into consideration. Specifically, let's assume a scenario where a UE a user in a vehicle carries communicates with a sensor, a screen monitor, etc. in the vehicle and therefore provides an infortainment service. In this scenario, when configuration information on the surroundings which vary with dynamical environment and time is provided, the SFC controller may determine a proper service function chain (SFC). In this case, too, as long as a security scheme based on biological information such as fingerprints, iris scans, etc. is used, the SFC controller may determine a codec suitable for each sensor and determine whether to employ a security module or not.

(92) In the above, the information the UE provides to the SFC controller may be provided to the network as direct values—that is, absolute values of speed, direction, sensor name, and sensor capability. Alternatively, the information the UE provides to the SFC controller may be provided as an implicative value, based on predefined configuration information. For example, for an up-train travelling at 100 km/hour or higher, the UE may provide a value of 01 as speed information and a value of 11 as direction information, depending on predefined configuration information and format.

(93) Alternatively, in a case where information can be grouped by a combination of various configurations, grouped information may be provided as a meaningful value. For example, for an up-train travelling at 100 km/hour or higher, information is grouped according to a combination of configurations, allowing the UE to provide a value 1. Moreover, for a sensor capable of measuring body temperature and heartbeat, information is grouped according to a combination of configurations, allowing the UE to provide a value 2.

(94) FIG. 11 shows an example in which virtual functions (VF) within a UE are considered/managed when determining a service function chain (SFC) according to another disclosure of the present specification.

(95) As can be seen with reference to FIG. 11, virtual functions (VF) may exist within a UE 100, and some of the virtual functions (VF) may constitute a sub-chain, like a network. For example, it may not be necessary for a 5G mobile communication system to perform UE IP address allocation or user plane session management. That is, the UE may be non-IP, and the UE is expected to be capable of data transmission through the control plane. Thus, the UE may require IP address management or not depending on the service it uses, and functions for IP address management may be included in the service function chain (SFC) or not. The UE may determine internally required virtual functions (VF) (to this end, the UE may internally have a control function), and or may determine the service function chain (SFC) via communication with the SFC controller 600. Moreover, particular information from each module may be provided to the network and taken into consideration when determining the service function chain (SFC).

(96) FIG. 12 shows an example in which a number of UEs are considered/managed when determining a service function chain (SFC) according to yet another disclosure of the present specification.

(97) As shown in FIG. 12, when UEs perform cooperative communication using communication technologies such as D2D, WLAN, and Bluetooth, the SFC controller may determine the service function chain (SFC) by taking such cooperative communication into consideration. Each terminal may be a device such as a sensor or monitor that cannot be connected directly to the SFC controller, i.e., that is incapable of wireless communication with a mobile communication core network. In this case, all the UEs may be connected to the SFC controller, or a representative UE alone may be connected to the SFC controller.

(98) The SFC controller may view each terminal as a virtual function (VF) and take this into consideration when determining the entire service function chain (SFC).

(99) FIG. 13 shows a process of determining a service function chain (SFC) by taking UE/terminal state information into consideration, in the example shown in FIG. 11.

(100) First, VNF #1 (e.g., UP function) and VNF #2 (e.g., CP function) may transmit their state information and network environment information to the SFC controller 600 periodically or when an event occurs. A business operator policy database (DB) (e.g., PCRF) transmits an operator policy (e.g., a business operator policy on session management) to the SFC controller 600 periodically or when an event occurs. A subscriber information DB (e.g., HSS) transmits subscriber information to the SFC controller 600 periodically or when an event occurs.

(101) Meanwhile, the UE/terminal 100 transmits state information (e.g., load information, capacity information, etc.) and configuration information (e.g., available sensor information, software type information, and activation information) of internal VFs to the SFC controller 600 periodically or when an additional event occurs. In this case, the UE/terminal 100 may aggregate information from the internal VFs and then send it, or each VF may send its information to the SFC controller 600. When the UE/terminal 100 aggregates and sends the information, the UE/terminal 100 may process/select the information and then send it.

(102) Then, the SFC controller 600 determines a service function chain (SFC) and information the UE/terminal 100 about this. Alternatively, the SFC controller 600 may transmit information on the service function chain (SFC) to a representative VF in the UE/terminal 100. Then, the representative VF in the UE/terminal 100 may transmit it to other VFs.

(103) Meanwhile, the SFC controller 600 may perform the determination and update of a sub-chain between the internal VFs, as well as the determination and update of the service function chain (SFC). That is, the SFC controller 600 may assume that the sub-chain between the internal VFs in the UE/terminal 100, too, is part of the service function chain (SFC). In this case, the SFC controller 600 may determine the sub-chain within a range that the business operator policy and the subscriber policy permit. Particularly, the sub-chain is determined to reduce delay or increase the availability of network resources, by considering the possibility of resource utilization.

(104) According to Option 1 shown in the drawing, the SFC controller 600 may determine the sub-chain and then inform the UE/terminal 100 about this. Alternatively, the SFC controller 600 may transmit information on the sub-chain to each VF in the UE/terminal 100.

(105) According to Option 2 shown in the drawing, the SFC controller 600 may decide that there is a need to determine a sub-chain, and actually entrust/request the UE/terminal 100 with/for the sub-chain. The SFC controller 600 normally performs central control, but, if the network range is wide, manage the sub-chain through distributed control, thereby ensuring the independence of the sub-chain and improving flexibility and efficiency. That is, the UE/terminal 100 may determine the sub-chain based on one or both of the received service function chain (SFC) information and its VF information and transmit information on the determined sub-chain to the SFC controller 600. Alternatively, the representative VF, among the VFs in the UE/terminal 100, may determine a sub-chain and transmit information on the sub-chain to other VFs and the SFC controller 600.

(106) In a case where the sub-chain information is determined and then transmitted to the SFC controller 600 by the UE/terminal 100 or the representative VF in the UE/terminal 100, the sub-chain information may act as another factor that alters the entire service function chain (SFC).

(107) If the configuration information of the UE/terminal 100 is frequently changed but not transmitted to the SFC controller 600 in real time, Option 2 may be more useful than Option 1.

(108) While the above description has been given with respect to a sub-chain between VFs in the UE/terminal 100, the description may also apply to a sub-chain in some part of the network.

(109) FIG. 14 shows a process of determining a service function chain (SFC) by taking UE/terminal state information into consideration, in the example shown in FIG. 12.

(110) Like what has been explained with reference to FIG. 13, VNF #1 (e.g., UP function) and VNF #2 (e.g., CP function) may transmit their state information and network environment information to the SFC controller 600 periodically or when an event occurs. A business operator policy database (DB) (e.g., PCRF) transmits an operator policy (e.g., a business operator policy on session management) to the SFC controller 600 periodically or when an event occurs. A subscriber information DB (e.g., HSS) transmits subscriber information to the SFC controller 600 periodically or when an event occurs.

(111) Meanwhile, the UEs/terminals 100a and 100b transmit their state information (e.g., load information, capacity information, etc.) and configuration information (e.g., available sensor information, software type information, and activation information) of internal VFs to the SFC controller 600 periodically or when an additional event occurs. In this case, the UEs/terminals 100a and 100b each may send their own information to the SFC controller, or the representative UE/terminal 100b may aggregate and send the information. When the representative UE/terminal 100b aggregates and sends the information, the representative UE/terminal 100b may process/select the information and then send it.

(112) Then, the SFC controller 600 determines a service function chain (SFC) and information the UEs/terminals 100a and 100b about this. Alternatively, the SFC controller 600 may transmit information on the service function chain (SFC) to the representative UE/terminal 100b. In this case, the representative UE/terminal 100b may transmit the information on the service function chain (SFC) to the other UE/terminal 100a.

(113) Meanwhile, the SFC controller 600 may perform the determination and update of a sub-chain between the UEs/terminals 100a and 100b, as well as the determination and update of the service function chain (SFC). That is, the SFC controller 600 may assume that the sub-chain between the UEs/terminals 100a and 100b, too, is part of the service function chain (SFC). In this case, the SFC controller 600 may determine the sub-chain within a range that the business operator policy and the subscriber policy permit. Particularly, the sub-chain is determined to reduce delay or increase the availability of network resources, by considering the possibility of resource utilization.

(114) According to Option 1 shown in the drawing, the SFC controller 600 may determine the sub-chain between the UEs/terminals 100a and 100b and then inform the UEs/terminals 100a and 100b about this. Alternatively, the SFC controller 600 may transmit information on the sub-chain to the representative UE/terminal 100b. Then, the representative UE/terminal 100b may transmit this to the other UE/terminal 100a

(115) According to Option 2 shown in the drawing, the SFC controller 600 may decide that there is a need to determine a sub-chain, and actually entrust/request the representative UE/terminal 100b with/for the sub-chain. The SFC controller 600 normally performs central control, but, if the network range is wide, manage the sub-chain through distributed control, thereby ensuring the independence of the sub-chain and improving flexibility and efficiency. That is, the representative UE/terminal 100b may determine the sub-chain based on one or both of the received service function chain (SFC) information and the information on the other UE/terminal 100a and transmit information on the determined sub-chain to the SFC controller 600 and the other UE/terminal 100a.

(116) In a case where the sub-chain information is determined and then transmitted to the SFC controller 600 by the representative UE/terminal 100b, the sub-chain information may act as another factor that alters the entire service function chain (SFC).

(117) While the above description has been given with respect to a sub-chain between the UEs/terminals 100a and 100b, the description may also apply to a sub-chain in some part of the network.

(118) What has been described so far may be implemented by hardware. This will be explained with reference to FIG. 15.

(119) FIG. 15 is a block diagram of the components of a UE 100 and network node according to an embodiment of the present invention.

(120) As shown in FIG. 18, the UE 100 includes a storage means 101, a controller 102, and a transceiver 103. The network node may be the SFC controller 600. The network node includes a storage means 601, a controller 602, and a transceiver 603.

(121) The storage means store the above-described method.

(122) The controllers control the storage means and the transceivers. Specifically, the controllers respectively execute the methods stored in the storage means. The controllers send the above-described signals through the transceivers.

(123) Although preferred embodiments of the present invention have been illustratively described, the scope of the present invention is not limited to only the specific embodiments, and the present invention may be modified, changed, or improved in various forms within the spirit of the present invention and a category written in the claims.