JP2024031529A - Control apparatus, control method, and program - Google Patents

Abstract

To provide a control apparatus and method for improving cache efficiency.SOLUTION: One or more control apparatuses as a physical computer on a telco cloud, includes a first processing unit (MEC-CDN control unit) which controls a network configuration of a plurality of cache servers constituting a MEC-CDN (Multi-access Edge Computing-enabled Contents Delivery Network) connected to a core network of a mobile communication network. The cache server includes a reverse proxy that relays a user access to a content, and a cache storage that is a memory region capable of storing the content temporally. The reverse proxy accesses to the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage. The first processing unit divides the virtual network or couples the plurality of virtual networks.SELECTED DRAWING: Figure 9

Description

The present invention relates to a control device, a control method, and a program.

In recent mobile communication networks, attention has been paid to locating computing resources (MEC: Multi-access Edge Computing) near user terminals (UE: User Equipment) and utilizing MEC. By distributing data from an MEC that is geographically close to the user terminal, it is possible to reduce network load and delay compared to the case where data is distributed from a server located on the Internet.

Various technologies related to MEC have been developed. For example, Patent Document 1 listed below discloses a technique for communicating user access to a backup secondary edge server instead of a normally used primary edge server due to congestion or failure of the edge server.

JP2019-041266A

However, the technology described in Patent Document 1 has only recently been developed, and there is still room for improvement from various viewpoints. For example, there is still room for improvement in cache efficiency.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a mechanism that can further improve cache efficiency.

In order to solve the above problems, according to one aspect of the present invention, a plurality of caches constituting an MEC-CDN (Multi-access Edge Computing-enabled Contents Delivery Network) connected to a core network of a mobile communication network are provided. The cache server includes a first processing unit that controls a network configuration of the server, and the cache server includes a reverse proxy that relays user access to the content, and a cache storage that is a storage area that can temporarily store the content. and the reverse proxy accesses the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage, and the first processing unit divides the virtual network, or divides the virtual network into a plurality of A controller is provided that couples the virtual networks.

Further, in order to solve the above problems, according to another aspect of the present invention, a third process for managing information regarding a plurality of cache servers configuring an MEC-CDN connected to a core network of a mobile communication network. and a fourth processing unit that adds a new cache server based on an index related to cache processing in the plurality of cache servers that constitute the MEC-CDN, and the third processing unit adds a new cache server. A control device is provided that, when the cache server is added, registers information regarding the newly added cache server.

Moreover, in order to solve the above-mentioned problem, according to another aspect of the present invention, there is provided a control method executed by a computer, wherein the control method includes an MEC- controlling the network configuration of a plurality of cache servers forming a CDN (Multi-access Edge Computing-enabled Contents Delivery Network), wherein the cache server includes a reverse proxy that relays user access to content, and a reverse proxy that relays user access to content; a cache storage which is a storage area that can temporarily store the data, the reverse proxy accesses the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage, and the reverse proxy accesses the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage, A control method is provided in which controlling the network configuration of the plurality of cache servers configuring the MEC-CDN includes dividing the virtual network or combining the plurality of virtual networks.

Moreover, in order to solve the above-mentioned problem, according to another aspect of the present invention, there is provided a control method executed by a computer, wherein the control method includes an MEC- The method includes: managing information regarding a plurality of cache servers constituting a CDN; and adding a new cache server based on an index related to cache processing in a plurality of cache servers constituting the MEC-CDN. , managing information regarding the plurality of cache servers configuring the MEC-CDN includes, when a new cache server is added, registering information regarding the newly added cache server; A control method is provided.

Further, in order to solve the above problems, according to another aspect of the present invention, a computer is connected to a core network of a mobile communication network using an MEC-CDN (Multi-access Edge Computing-enabled Contents Delivery Network). The cache server functions as a first processing unit that controls the network configuration of a plurality of cache servers that constitute the cache server, and the cache server includes a reverse proxy that relays user access to content, and a storage area that can temporarily store the content. a cache storage, the reverse proxy accesses the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage, and the first processing unit A program is provided for dividing a plurality of virtual networks or for combining a plurality of said virtual networks.

Moreover, in order to solve the above-mentioned problem, according to another aspect of the present invention, a computer is configured to manage information regarding a plurality of cache servers constituting an MEC-CDN connected to a core network of a mobile communication network. The third processing unit functions as a third processing unit and a fourth processing unit that adds a new cache server based on an index related to cache processing in a plurality of cache servers forming the MEC-CDN, and the third processing unit provides a program that, when a new cache server is added, registers information regarding the newly added cache server.

As explained above, according to the present invention, a mechanism capable of further improving cache efficiency is provided.

FIG. 2 is a diagram for explaining an example of a network configuration within a communication carrier including a mobile communication network. 1 is a diagram illustrating an example of a configuration of the Internet and a CDN configured on the Internet; FIG. FIG. 2 is a diagram illustrating an example of an arrangement position of an MEC in the intra-communications carrier network illustrated in FIG. 1. FIG. FIG. 2 is a diagram illustrating an example of a configuration of an MEC-CDN implemented on a teleco cloud. FIG. 2 is a diagram illustrating an example of access control from a UE to a cache server in MEC-CDN. It is a diagram showing an example of the configuration of a telecom cloud according to the first embodiment. It is a sequence diagram which shows an example of the flow of the cache server addition process performed in the teleco cloud based on the same embodiment. It is a sequence diagram which shows an example of the flow of the content acquisition process performed in the teleco cloud based on the same embodiment. It is a figure showing an example of the composition of the teleco cloud concerning a 2nd embodiment. FIG. 2 is a sequence diagram illustrating an example of the flow of virtual IP storage configuration control processing executed by the teleco cloud according to the embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Note that, in this specification and the drawings, components having substantially the same functional configurations are designated by the same reference numerals and redundant explanation will be omitted.

Further, in this specification and the drawings, elements having substantially the same functional configuration may be distinguished by using the same reference numerals followed by different alphabetic or numerical indices. For example, a plurality of elements having substantially the same functional configuration may be distinguished as devices 99A, 99B, 99-1, and 99-2 as necessary. However, if there is no particular need to distinguish between a plurality of elements having substantially the same functional configuration, the index will be omitted and only the same reference numerals will be given. For example, devices 99A, 99B, 99-1, and 99-2 are simply referred to as device 99 when there is no need to distinguish them.

<1. Prerequisite technology>
In recent years, in intra-communication carrier networks including mobile communication networks, attention has been paid to placing MECs close to UEs and utilizing MECs. A carrier network including a mobile communication network is provided by a mobile network operator (MNO: Mobile Network Operator). At present, a 5th Generation Mobile Communication System (5G) is used as an example of a mobile communication system. 5G is implemented based on the 3GPP (3rd Generation Partnership Project, registered trademark) mobile communication system reference architecture. 3GPP is an organization that standardizes wireless communication systems that satisfy the regulations "IMT-2020" set by the International Telecommunication Union (ITU). An example of the configuration of a carrier network including a mobile communication network will be described below with reference to FIG. 1.

(1) Example of an intra-communication carrier network configuration including a mobile communication network FIG. 1 is a diagram for explaining an example of an intra-communication carrier network configuration including a mobile communication network. As shown in FIG. 1, the intra-communication carrier network 1 includes a central DC (Data Center) 11, a regional DC 12, a GC (Group Unit Center) 13, and a BS (Base Station) 14. A communication carrier network 1 is connected to the Internet 2 via an Internet 2 connection service provided by an ISP (Internet Service Provider). In addition, the intra-communication carrier network 1 connects to the intra-communication carrier network 1 and the Internet 2, and connects to the UE (User Equipment) 3 used by a user who has a contract for a service that provides data communication over the connection. , connected.

The central DC 11, regional DC 12, and GC 13 are data centers. The central DC 11 is a high-level data center, the regional DC 12 is a middle-level data center, and the GC 13 is a low-level data center. One or more regional DCs 12 are arranged under one regional DC 12, one or more GCs 13 are arranged under one regional DC 12, and one or more BSs 14 are connected to one GC 13. The upper data center and the lower data center are connected via a network. These data centers are geographically dispersed.

The BS 14 is a device that is wirelessly connected to a UE 3 located within a range that can transmit and receive wireless signals to and from the BS 14, and transmits and receives wireless signals between the UE 3 and the wirelessly connected UE 3. The BS 14 relays communication between the wirelessly connected UE 3 and the central DC 11, regional DC 12, GC 13, or the Internet 2.

UE3 is a user terminal operated by a user. UE3 may be any information processing device such as a smartphone or a PC (Personal Computer). UE3 wirelessly connects to connectable BS14. UE3 is a source of user access to content such as videos.

The connection points between the mobile communication network included in the intra-communication carrier network 1 and the Internet 2 are consolidated. That is, the Internet 2 is connected to the central DC 11 of the intra-communication carrier network 1. Communication between central DC 11 and UE 3 is performed via regional DC 12, GC 13, and BS 14. As the topology of the network connecting these devices, a ring structure, peer-to-peer connection, or the like may be adopted. Hereinafter, the side of the intra-communication carrier network 1 that is closer to the central DC 11 will also be relatively referred to as the center side. On the other hand, the side of the intra-communication carrier network 1 that is closer to the BS 14 is also relatively referred to as the edge side.

Contents Delivery Network (CDN) is a major use case that utilizes MEC. Therefore, an example of the configuration of the Internet 2 and a CDN configured on the Internet 2 will be described with reference to FIG. 2.

(2) Configuration example of CDN FIG. 2 is a diagram showing an example of the configuration of the Internet 2 and a CDN configured on the Internet 2. As shown in FIG. 2, the Internet 2 includes an ISP 15, an IX (Internet eXchange) 16, and a DC 17. Connection between the mobile communication network included in the intra-communication carrier network 1 and the Internet 2 is provided by the ISP 15. The Internet 2 is a collection of individual autonomous systems (AS). ISP15 also forms one AS. Connection forms between ASs on the Internet 2 include peering and transit. Peering is a form in which ASs connect with each other and directly exchange each other's traffic without passing through another network. There are two types of peering: a connection via the IX 16 (also referred to as public peering) and a direct connection not via the IX 16 (also referred to as private peering). Transit is a form in which one autonomous system provides connectivity to the entire Internet 2 to another.

In a CDN configured on the Internet 2, the origin server 19 is placed in a DC 17 that is close to the company's own equipment or to each major ISP 15. The cache server 18 is mainly located at the ISP 15 close to the user. The origin server 19 is a server that stores original data of content. The cache server 18 is a server that temporarily stores (that is, caches) content acquired from the origin server 19. More specifically, the cache server 18 is a reverse proxy with a cache function, and temporarily stores the relayed data in cache storage. By distributing content from the cache server 18 located on the edge side, it is possible to suppress the access load on the origin server 19 and the network load on the network path from the origin server 19 to the ISP 15.

In contrast to the above-described CDN configured on the Internet 2, a CDN utilizing MEC is also referred to as an MEC-CDN (MEC-enabled CDN). The MEC-CDN will be explained below with reference to FIG. 3.

(3) Configuration example of MEC-CDN FIG. 3 is a diagram showing an example of the arrangement position of the MEC 20 (20-1 to 20-3) in the intra-communication carrier network 1 shown in FIG. In the example shown in FIG. 3, the MEC 20-1 is placed in the central DC 11, the MEC 20-2 is placed in the regional DC 12, and the MEC 20-3 is placed in the GC 13.

The MEC 20 is a computing resource placed in a data network (DN) connected to a core network of a mobile communication network included in the intra-communication carrier network 1. The MEC 20 is located closer to the UE 3 than the Internet 2. A cache server 30 is arranged in the MEC 20. Specifically, a cache server 30-1 is placed in the MEC 20-1, a cache server 30-2 is placed in the MEC 20-2, and a cache server 30-3 is placed in the MEC 20-3. The configuration of cache server 30 is similar to that of cache server 18. A plurality of cache servers 30 connected to the core network constitute the MEC-CDN.

In recent years, the implementation of the intra-communication carrier network 1 including the core network of a mobile communication network has been transitioning to implementation on a virtual machine such as a Telco Cloud managed by the communication carrier. It is easy to imagine that data transmission based on the IP protocol will be performed closer to the edge on the teleco cloud. This means that the MEC 20 can be distributed and placed closer to the UE 3. However, since the MEC 20 closer to the UE 3 has fewer UEs 3 with which it can communicate via the core network of the mobile communication network, it typically has a configuration with fewer available resources.

A virtual machine is a computer that uses software to implement the same functions as a physical computer, including arithmetic circuits such as a CPU (Central Processing Unit) and storage media such as an SSD (Solid State Drive). runs on any computer. Each component on the teleco cloud runs on one or more controllers that are physical computers.

The configuration of the MEC-CDN implemented on the teleco cloud will be described below with reference to FIG. 4.

FIG. 4 is a diagram showing an example of the configuration of MEC-CDN implemented on the teleco cloud. As shown in FIG. 4, in the teleco cloud 100, a 5G network 5, an intranet network 4, one or more MEC hosts 110 (110A and 110B), and a management host 120 are implemented on virtual machines. MEC host 110 is an implementation of MEC 20 shown in FIG. The management host 120 manages one or more MECs 20 placed in the teleco cloud 100.

The MEC host 110 corresponds to the MEC 20 shown in FIG. MEC host 110 includes MEC platform 111 and MEC application 112. Note that illustration of the MEC platform 111 and MEC application 112 included in the MEC host 110B is omitted.

The MEC platform 111 performs life cycle management of the MEC application 112. That is, the MEC platform 111 instantiates the MEC application 112 or deletes the instance of the MEC application 112. Instantiation of MEC application 112 is performed using resources within MEC host 110. An example of resources within MEC host 110 is storage space and computing power. The MEC platform 111 performs life cycle management of the MEC application 112 based on control by the MEC platform management section 121.

The MEC application 112 corresponds to the cache server 30 shown in FIG. The "cache server" that appears in the following description refers to the MEC application 112 unless otherwise specified. MEC application 112 includes reverse proxy 113 and cache storage 114.

Cache storage 114 is a storage area that can cache content.

Reverse proxy 113 relays user access to content. As an example, regarding user access to content cached in the cache storage 114, the reverse proxy 113 obtains the content cached in the cache storage 114 and sends it to the UE3. As another example, regarding user access to content that is not cached in the cache storage 114, the reverse proxy 113 acquires the content from the outside, caches it in the cache storage 114, and transmits it to the UE3.

Here, the reverse proxy 113 is a server located within the DN in the 5G system architecture. Reverse proxy 113 is connectable from UE 3 via 5G network 5 . Furthermore, the reverse proxy 113 can be connected to the Internet 2 via the internal network 4 . The connection of the reverse proxy 113 to the Internet 2 via the internal network 4 is also referred to as local breakout. The local breakout is used as a communication path when acquiring content from the cache server 18 or origin server 19 on the Internet 2 shown in FIG. Reverse proxy 113 may obtain content that is not cached in cache storage 114 from outside via local breakout.

Note that the reverse proxy 113 acquires cached content from the cache storage 114 connected to the reverse proxy 113, or causes the cache storage 114 to cache content acquired from the outside via local breakout. In the example shown in FIG. 4, a reverse proxy 113 and a cache storage 114 installed in the same MEC host 110 are connected.

The management host 120 includes an MEC platform management section 121, a MEC-CDN access control section 122, and an OSS/BSS (Operation Support Systems/Business Support Systems) 123.

The MEC platform management unit 121 is an example of a fourth processing unit that manages the operations of the plurality of MEC hosts 110 that operate the plurality of cache servers that constitute the MEC-CDN. For example, the MEC platform management unit 121 controls the life cycle of the MEC application 112 via the MEC platform 111. Note that in FIG. 4, illustration of connections between the MEC platform management unit 121 and MEC hosts 110 other than the MEC host 110A is omitted.

The MEC-CDN access control unit 122 is an example of a second processing unit that controls user access to content cached in a plurality of cache storages 114 included in a plurality of cache servers configuring the MEC-CDN. Specifically, the MEC-CDN access control unit 122 performs name resolution in the MEC-CDN. For example, the MEC-CDN access control unit 122 stores the IP addresses of each component (eg, reverse proxy 113 and cache storage 114) on the MEC-CDN. Then, the MEC-CDN access control unit 122 distributes user access to the plurality of reverse proxies 113.

The OSS/BSS 123 makes a request regarding the MEC application 112 to the MEC platform management unit 121. The OSS/BSS 123 requests the MEC platform management unit 121 to instantiate MEC applications 112 implemented for various uses such as, for example, a cache server of the MEC-CDN. In addition to a cache server, the MEC application 112 may be used to perform high-speed processing of part of the calculation processing of the UE 3 using the resources of the MEC host 110.

Next, access control to the cache server will be explained with reference to FIG. 5.

FIG. 5 is a diagram showing an example of access control from the UE3 to the cache server in the MEC-CDN. In FIG. 5, among the components shown in FIG. 4, components that have little involvement in access control are omitted. As shown in FIG. 5, an intra-communication carrier DNS (Domain Name System) 130 is arranged in the intra-network 4 within the teleco cloud 100. On the other hand, a MEC-CDN access control unit 122 is arranged in the management host 120. The intra-communications carrier DNS 130 performs name resolution on the telecom cloud 100. On the other hand, the intra-communications carrier DNS 130 delegates name resolution processing to the MEC-CDN access control unit 122 for domain names operated by the MEC-CDN. That is, the MEC-CDN access control unit 122 performs name resolution for domain names operated by the MEC-CDN. In particular, the MEC-CDN access control unit 122 distributes user access to a plurality of reverse proxies 113 during name resolution.

Note that in FIGS. 4 and 5, the MEC-CDN access control unit 122 is located within the management host 120, but the present invention is not limited to such an example. The MEC-CDN access control unit 122 may be implemented as an MEC application with a function different from that of the MEC application 112.

An example of the configuration of the MEC-CDN has been described above.

The advantages of configuring the MEC-CDN include reducing the amount of communication to the Internet 2 side and shortening the time for data transfer to the UE 3 by distributing content from a cache server closer to the UE 3. The cache efficiency tends to improve as more cache servers are placed in the MEC host 110 on the center side. This is because the MEC host 110 on the center side has a larger amount of available resources and a larger number of accessible UEs 3. On the other hand, cache efficiency tends to decrease as the cache server is placed in the MEC host 110 on the edge side. This is because the MEC host 110 on the edge side has a smaller amount of available resources and a smaller number of accessible UEs 3.

However, if there is no cache hit in the cache server, the content is acquired from the Internet 2 side via local breakout. In that case, in addition to communication with the ISP 15 shown in FIG. 2, peering or transit communication for acquiring content from the cache server 18 or origin server 19 will occur.

<2. Technical issues>
In MEC-CDN, a decrease in cache efficiency in a cache server means that communication for acquiring data from the Internet 2 due to local breakout increases. Furthermore, an increase in communication for acquiring data from the Internet 2 due to local breakout may cause congestion on the Internet 2. As a result, communication costs become high for businesses providing MEC-CDN.

Further, the OSS/BSS 123 makes various requests to the MEC platform management section 121. Therefore, available resources within the MEC host 110 change over time. Therefore, it has been difficult to ensure a size of the cache storage 114 that is suitable for access from the UE 3, especially in the edge-side cache server. This caused a decline in cache efficiency.

<3. Technical features>
<3.1. First embodiment>
(1) Configuration FIG. 6 is a diagram showing an example of the configuration of the telecom cloud 100 according to the present embodiment. Hereinafter, the characteristic configuration of this embodiment will be described with reference to FIG. 6. Note that configurations not specifically mentioned below are the same as the configurations described as the underlying technology with reference to FIGS. 1 to 5.

As shown in FIG. 6, a virtual IP storage network section 125 is arranged in the intranet network 4. The virtual IP storage network unit 125 is a virtual network that provides connectivity between the reverse proxy 113 and the cache storage 114. The reverse proxy 113 then accesses the cache storage 114 via the virtual IP storage network section 125. Specifically, the virtual IP storage network unit 125 stores the IP address of the cache storage 114 and performs routing regarding access from the reverse proxy 113 to the cache storage 114.

Here, as shown in FIG. 6, in this embodiment, the reverse proxy 113 and cache storage 114 on the same MEC host 110 are not directly connected. On the other hand, reverse proxy 113 and cache storage 114 are connected via virtual IP storage network section 125. Therefore, the reverse proxy 113 accesses any cache storage 114 via the virtual IP storage network section 125.

Furthermore, in the example shown in FIG. 6, the virtual IP storage network unit 125 connects all of the multiple reverse proxies 113 and all of the multiple cache storages 114 located in the multiple MEC hosts 110 that configure the MEC-CDN. , providing connectivity. Therefore, the reverse proxy 113 can access any cache storage 114 making up the MEC-CDN via the virtual IP storage network section 125. One or more cache storages 114 included in one or more cache servers configuring the MEC-CDN and whose connectivity is provided by the virtual IP storage network unit 125 are hereinafter collectively referred to as virtual IP storage. In this embodiment, the virtual IP storage can be accessed from any reverse proxy 113. Therefore, in any cache server, it becomes easy to secure the size of the virtual IP storage suitable for access from UE3.

As shown in FIG. 6, MEC host 110 includes MEC platform 111 and MEC application 112. The MEC application 112 includes a reverse proxy 113, a cache storage 114, and a virtual IP storage client 115. Note that illustration of the MEC platform 111, MEC application 112, and virtual IP storage client 115 included in the MEC host 110B is omitted.

The virtual IP storage client 115 is connected to the virtual IP storage management unit 124. The virtual IP storage client 115 then provides access to the virtual IP storage from the reverse proxy 113. The virtual IP storage client 115 requests the virtual IP storage management unit 124 to add/delete content in the cache storage 114.

As shown in FIG. 6, the management host 120 includes an MEC platform management section 121, a MEC-CDN access control section 122, an OSS/BSS 123, and a virtual IP storage management section 124. The virtual IP storage management unit 124 is connected to the virtual IP storage client 115, the MEC platform management unit 121, and the virtual IP storage network unit 125.

The MEC platform management unit 121 adds a new cache server or deletes an existing cache server. Specifically, the MEC platform management unit 121 instantiates a new MEC application 112 on the virtual machine to add a new cache server. On the other hand, the MEC platform management unit 121 deletes the instance of the MEC application 112 from the virtual machine by deleting the existing cache server. According to this configuration, it becomes possible to dynamically change the configuration of the MEC-CDN.

In particular, the MEC platform management unit 121 adds or deletes cache servers based on indicators related to cache processing in a plurality of cache servers making up the MEC-CDN. The index regarding cache processing here may be related to cache efficiency, and the MEC platform management unit 121 may add or delete a cache server using a deterioration in cache efficiency as a trigger. Specifically, cache efficiency may be calculated based on at least one of cache hit rate and latency. According to this configuration, it is possible to dynamically change the configuration of the MEC-CDN and improve cache efficiency.

The virtual IP storage management unit 124 is an example of a third processing unit that manages information regarding a plurality of cache servers that constitute the MEC-CDN. More simply, the virtual IP storage management unit 124 manages information regarding virtual IP storage. Specifically, the virtual IP storage management unit 124 stores and updates a cache server placement list, a storage management list, a content cache list, and a content placement list.

The cache server placement list is a list that includes information indicating the placement of a plurality of cache servers constituting the MEC-CDN in the intra-communication carrier network 1. The cache server placement list reflects the configuration of the user plane of the 5G network 5. Note that the user plane refers to user data transmission and reception processing. Table 1 shows an example of the cache server placement list.

As shown in Table 1, the cache server placement list may include "position", "address", and "node type" as items. “position” is identification information indicating the location of the cache server, such as the central DC 11, regional DC 12, or GC 13. In particular, the initial letter "R" indicates region DC12. The initial letter "G" indicates GC13. “Address” is an address used when connecting from the UE 3 to the cache server via the 5G network 5. "Node type" indicates the type of cache server. In particular, "R" indicates a root node and "L" indicates a leaf node. A leaf node is a cache server placed on the edge side. The root node is a cache server placed on the center side. The root node is the physical location and network decomposition point for user access control.

The cache server placement list has been explained above. Next, the storage management list will be explained.

The storage management list is a list that includes information on a plurality of cache storages 114 included in a plurality of cache servers configuring the MEC-CDN. Table 2 shows an example of the storage management list.

As shown in Table 2, the storage management list may include "storage ID," "position," "Address," "total size," "free size," and "reserved size" as items. “Storage ID” is identification information of the cache storage 114 in the MEC-CDN. "position" and "address" are as explained above with reference to Table 1. “Total size” is the total size of cache storage 114. “Free size” is the free capacity of the cache storage 114. "Reserved size" is reserved capacity. Note that the reserved capacity here indicates the total size of content that has been acquired through local breakout.

The storage management list has been explained above. Next, the content cache list will be explained.

The content cache list is a list containing information about content cached in a plurality of cache storages 114 included in a plurality of cache servers configuring the MEC-CDN. Table 3 shows an example of the content cache list.

As shown in Table 3, the content cache list may include "content ID", "TTL", "last update time", and "last access time" as items. "Content ID" is identification information uniquely assigned to content cached in the virtual IP storage. It is assumed that the "content ID" has already been assigned when the user accesses the content from the UE3. "TTL" is an abbreviation for "Time to Live" and indicates the expiration date of cached content. "Last update time" is the date and time when the cached content was last updated. For example, after the time elapsed since the "last update time" reaches a "TTL", it may be necessary to check whether the content has been updated via a local breakout. "Last access time" is the date and time when the cached content was last accessed. For example, when a predetermined period of time has passed since the "last access time", cached content is deleted.

The virtual IP storage management unit 124 may create a content cache list for each root node. Further, the virtual IP storage management unit 124 may manage the cached contents by ordering them based on time information such as "last update time". As an example, when the free space of the cache storage 114 decreases, the virtual IP storage management unit 124 may delete caches in order from the lowest content on the content cache list.

The content cache list has been explained above. Next, the content arrangement list will be explained.

The content placement list is a list that includes information indicating cache positions of content in a plurality of cache storages 114 included in a plurality of cache servers configuring the MEC-CDN. Table 4 shows an example of the content arrangement list.

As shown in Table 4, the content placement list may include "content ID," "storage ID," "content path," "content size," and "status" as items. The “content ID” is as explained above with reference to Table 3. “Storage ID” is identification information of the cache storage 114 as the cache destination. “Content path” is the storage location of the content in the cache storage 114 as the cache destination. "Content size" is the size of cached content. "Status" is the cache state of the content. The cache status includes "Create" indicating that the data is being acquired, "Store" indicating that the data has been saved, "Update" indicating that the data is being updated, and "Delete" indicating that the data is being deleted. Depending on the cache state, access permission to the content is controlled, and the "reserved size" in the storage management list shown in Table 2 is changed.

The cache server placement list, storage management list, content cache list, and content placement list managed by the virtual IP storage management unit 124 have been described above. Note that the cache server placement list may also be managed by the MEC-CDN access control unit 122. This is because it is used during name resolution in MEC-CDN. Of course, the MEC-CDN access control unit 122 may refer to the cache server placement list managed by the virtual IP storage management unit 124 during name resolution.

The virtual IP storage management unit 124 updates the cache server placement list, storage management list, content cache list, or content placement list when a change occurs in the configuration of the MEC-CDN or the content cache state. As an example, when a new cache server is added, the virtual IP storage management unit 124 may register information regarding the newly added cache server. As another example, when an existing cache server is deleted, the virtual IP storage management unit 124 may delete information regarding the deleted cache server. As another example, the virtual IP storage management unit 124 may update the cache server placement list in response to movement of the MEC host 110 or the cache server. As another example, the virtual IP storage management unit 124 may update the content cache list and the content placement list when a content cache is added, deleted, or updated in the cache storage 114. According to this configuration, it is possible to keep the cache server placement list, storage management list, content cache list, and content placement list up to date.

The virtual IP storage management unit 124 transmits information indicating whether or not there is a valid cache for the content to the reverse proxy 113 when the reverse proxy 113 relays user access to the content. For example, the virtual IP storage management unit 124 refers to the content cache list, determines whether there is a valid cache for the content, and transmits the determination result to the reverse proxy 113. The reverse proxy 113 acquires the content from the virtual IP storage if the virtual IP storage has a valid cache of the content. On the other hand, the reverse proxy 113 retrieves the content via local breakout if there is no valid cache of the content in the virtual IP storage.

The virtual IP storage management unit 124 may transmit information indicating the cache location of the content as well as information indicating whether there is a valid cache for the content to the reverse proxy 113 that relays user access to the content.

Specifically, if there is a valid cache for the content, the virtual IP storage management unit 124 sends information indicating the cache storage 114 caching the content to the reverse proxy 113 as information indicating the cache location of the content. You may. For example, the virtual IP storage management unit 124 refers to the storage management list and the content placement list and transmits the IP address and content path of the cache storage 114 caching the content to the reverse proxy 113. Based on such information, the reverse proxy 113 can obtain the cached content and send it to the user access source UE3.

On the other hand, if there is no valid cache for the content, the virtual IP storage management unit 124 converts information indicating the cache storage 114 that should cache the content acquired via local breakout into information indicating the cache location of the content. , and sends it to the reverse proxy 113. The cache location here is the cache storage 114 where content obtained via local breakout should be cached. The reverse proxy 113 transmits the content acquired via local breakout to the UE 3 that is the user access source, and causes the content to be cached in the cache storage 114 specified by the virtual IP storage management unit 124 . According to this configuration, it becomes possible to appropriately control the cache location of content.

At that time, the virtual IP storage management unit 124 determines whether the content has been acquired via local breakout based on at least one of the distance from the UE 3, which is the source of user access to the content, and the free space of the cache storage 114. A cache storage 114 may be selected to cache the content. For example, the virtual IP storage management unit 124 refers to the cache server placement list and the storage management list and selects the cache storage 114 that is closer to the UE 3 and has more free space. According to this configuration, it is possible to cache the content in an appropriate cache storage 114.

(2) Processing - Cache server addition processing An example of the flow of processing when adding a cache server will be described below with reference to FIG.

FIG. 7 is a sequence diagram showing an example of the flow of cache server addition processing executed in the teleco cloud 100 according to the present embodiment. This sequence involves the OSS/BSS 123, the MEC platform management section 121, the MEC platform 111, the MEC-CDN access control section 122, the MEC host 110, the virtual IP storage management section 124, and the virtual IP storage network section 125. Note that the explanation of messages indicated by broken lines in this sequence may be omitted. The message is a response to the message sent and received in the previous stage, and includes processing results based on the message sent and received in the previous stage.

First, the OSS/BSS 123 transmits a request to add the MEC application 112 to the MEC platform management unit 121 (step S102). For example, the OSS/BSS 123 sends an additional request for the MEC application 112, triggered by detecting a decrease in cache efficiency in the MEC-CDN.

Next, upon receiving the request to add the MEC application 112, the MEC platform management unit 121 transmits a request to instantiate the MEC application 112 to the MEC platform 111 (step S104). At least one of the MEC platform management unit 121 and the MEC platform 111 determines the address of the reverse proxy 113 and the size of the cache storage 114 according to the resource status of the MEC.

Next, upon receiving the request to add the MEC application 112, the MEC platform 111 secures various resources necessary for instantiating the MEC application 112 on the MEC host 110 (step S106).

Then, the MEC platform 111 starts up the reverse proxy 113, cache storage 114, and virtual IP storage client 115 (steps S108, S110, and S112).

Next, the virtual IP storage client 115 transmits storage information to the virtual IP storage management unit 124 (step S114). The storage information includes, for example, various information to be input into the storage management list.

Next, the virtual IP storage management unit 124 transmits a configuration change request requesting to change the network configuration of the virtual IP storage to the virtual IP storage network unit 125 (step S116). The configuration change request is information requesting to change the network configuration on the internal network 4 so that the added cache storage 114 can communicate with the virtual IP storage network section 125. For example, the configuration change request includes the IP address of the activated cache storage 114.

Next, the virtual IP storage network unit 125 changes the network configuration of the virtual IP storage based on the configuration change request (step S118). Specifically, the virtual IP storage network unit 125 stores the IP address of the activated cache storage 114 and provides connectivity to the activated cache storage 114.

Next, if the network configuration is successfully changed and the added cache storage 114 can be referenced between the cache servers, the virtual IP storage management unit 124 stores information about the added cache storage 114 in the storage management list. (Step S120).

Next, the MEC platform management unit 121 transmits a cache server activation notification to the MEC-CDN access control unit 122 (step S122). The cache server activation notification includes information on the activated MEC application 112.

Next, the MEC-CDN access control unit 122 updates the cache server placement list based on the cache server activation notification (step S124). For example, the MEC-CDN access control unit 122 adds information about the activated cache server to the cache server placement list.

Furthermore, the MEC platform management unit 121 transmits a cache server activation notification to the virtual IP storage management unit 124 (step S126).

Next, the virtual IP storage management unit 124 updates the cache server placement list based on the cache server activation notification (step S128). For example, the virtual IP storage management unit 124 adds information about the activated cache server to the cache server placement list.

- Content Acquisition Process Hereinafter, with reference to FIG. 8, an example of a process flow when the UE3 accesses the MEC-CDN and acquires content will be described.

FIG. 8 is a sequence diagram showing an example of the flow of content acquisition processing executed in the telecom cloud 100 according to the present embodiment. This sequence includes the UE 3, intra-communications carrier DNS 130, MEC-CDN access control unit 122, MEC platform management unit 121, reverse proxy 113, virtual IP storage management unit 124, virtual IP storage network unit 125, cache storage 114, and Origin server 19 is involved. Note that the explanation of messages indicated by broken lines in this sequence may be omitted. The message is a response to the message sent and received in the previous stage, and includes processing results based on the message sent and received in the previous stage.

This sequence assumes the following: That is, it is assumed that an IPv4 private address (10.255.255.255/8) is assigned in the intranetwork 4 in the teleco cloud 100. It is assumed that there is an intra-communications carrier DNS 130 that performs name resolution in the telecom cloud 100, and that the intra-communications carrier DNS 130 is compatible with EDNS0 (Extension Mechanisms for DNS version 0). It is assumed that the intra-communications carrier DNS 130 delegates name resolution to the MEC-CDN access control unit 122 for domain names operated by the MEC-CDN. It is assumed that the MEC-CDN access control unit 122 can obtain from the MEC platform management unit 121 a list of MEC hosts 110 that can be accessed by the UE 3 via the 5G network 5.

In addition, if the MEC platform 111 is implemented in accordance with "ESTI GS MEC 013, MEC; Location API", information indicating the geographical location of UE3 such as "AccessPointID" and "ZoneID" is based on the IP address of UE3. Identification information can be obtained. Then, based on the "AccessPointID" and "ZoneID", it is possible to obtain the distances from the UE3 to the MEC host 110 and the MEC host 110 that are accessible from the UE3.

As shown in FIG. 8, the UE 3 transmits a name resolution request to the intra-communications carrier DNS 130 (step S202). The name resolution request includes, for example, the domain name of the content that UE3 attempts to access.

Next, the intra-communications carrier DNS 130 delegates name resolution processing to the MEC-CDN access control unit 122 (step S204). As an example, the intra-communications carrier DNS 130 transmits the name resolution request received from the UE 3 to the MEC-CDN access control unit 122. As another example, the intra-communications carrier DNS 130 responds to the UE3 with a domain name different from the domain name received from the UE3, and the UE3 sends a name resolution request based on the responded domain name to the MEC-CDN access control unit. 122.

Next, the MEC-CDN access control unit 122 transmits a cache server search request to the MEC platform management unit 121 (step S206-1), and obtains a list of cache servers accessible by the UE3 (step S206-1). 2). The cache server search request includes the subnet in which UE3 is included, which can be obtained from the query of the name resolution request. The MEC platform management unit 121 searches for a list of cache servers that can be accessed by the UE3 based on the subnet in which the UE3 is included, and sends the search results to the MEC-CDN access control unit 122.

Next, the MEC-CDN access control unit 122 selects one cache server from the list of cache servers (step S208). There are various strategies for the MEC-CDN access control unit 122 to select a cache server, such as round robin and edge side priority.

Next, the MEC-CDN access control unit 122 transmits the address of the reverse proxy 113 of the selected cache server to the intra-communication carrier DNS 130 (step S209-1).

Next, the intra-communication carrier DNS 130 transmits the received address of the reverse proxy 113 to the UE 3 (step S209-2).

Next, UE3 accesses reverse proxy 113 based on the received address and transmits a content request (step S210). The content request is information requesting to transmit content, and includes, for example, identification information of the content.

Next, the reverse proxy 113 makes an inquiry to the virtual IP storage management unit 124 via the virtual IP storage client 115 for information on the storage to be accessed (step S212). Here, the reverse proxy 113 makes an inquiry regarding the content related to the content request received from the UE3.

Next, the virtual IP storage management unit 124 refers to the content cache list and checks whether there is a valid cache for the target content (step S214). As an example, if the content cache list has the "content ID" of the target content and the current time is within "last update time" + "TTL", the virtual IP storage management unit 124 determines that there is a valid cache. do. As another example, if the content cache list does not include the "content ID" of the target content, the virtual IP storage management unit 124 determines that there is no valid cache. As another example, if the content cache list has the "content ID" of the target content, but the current time has passed "last update time" + "TTL", the virtual IP storage management unit 124 may not have a valid cache. It is determined that there is no such thing. As another example, the virtual IP storage management unit 124 determines that there is no valid cache when the status of the target content in the content placement list is "Delete".

Next, the virtual IP storage management unit 124 selects the cache storage 114 (step S216). Here, if it is determined in step S214 that there is a valid cache, the virtual IP storage management unit 124 selects the cache storage 114 that has a valid cache. On the other hand, if it is determined in step S214 that there is no valid cache, the virtual IP storage management unit 124 selects the cache storage 114 in which the content acquired via local breakout should be cached. At this time, the virtual IP storage management unit 124 may search the storage management list in order of distance (that is, order of proximity) based on the address of the reverse proxy 113. Then, the virtual IP storage management unit 124 may select the first cache storage 114 whose free capacity, obtained by subtracting the reserved capacity from the storage capacity, is equal to or larger than the content size.

Next, the virtual IP storage management unit 124 transmits information on the storage to be accessed to the reverse proxy 113 (step S217). For example, the virtual IP storage management unit 124 transmits information indicating whether there is a valid cache and the cache storage 114 selected in step S216 to the reverse proxy 113.

If there is no valid cache, the reverse proxy 113 acquires the content from the origin server 19 (or higher-level cache server) on the Internet 2 via local breakout (step S218). Next, the reverse proxy 113 stores the acquired content in the cache destination specified by the virtual IP storage management unit 124 in step S217 (step S220). At this time, the reverse proxy 113 accesses the cache storage 114 via the virtual IP storage network unit 125 and stores the content.

On the other hand, if there is a valid cache, the reverse proxy 113 acquires the content from the cache destination specified by the virtual IP storage management unit 124 in step S217 (step S222). At this time, the reverse proxy 113 accesses the cache storage 114 via the virtual IP storage network unit 125 and acquires the cached content.

After that, the reverse proxy 113 transmits the acquired content to the UE3 (step S224).

(3) Summary This embodiment has been described above. According to this embodiment, a plurality of cache storages 114 existing in a plurality of MEC hosts 110 can be handled as one virtual IP storage. Therefore, content cached in any one of the plurality of MEC hosts 110 can be used from any MEC host 110. As a result, it is expected that shortages of cache storage 114, especially on the edge side, will be avoided. Furthermore, it is expected to improve cache efficiency on the edge side in MEC-CDN.

<3.2. Second embodiment>
(1) Configuration In this embodiment, the configuration of the virtual IP storage is dynamically changed according to various parameters such as the number of accesses from the UE 3, cache hit rate, and network latency. Hereinafter, this embodiment will be described in detail with reference to FIG. 9.

FIG. 9 is a diagram showing an example of the configuration of the telecom cloud 100 according to the present embodiment. Hereinafter, the characteristic configuration of this embodiment will be described with reference to FIG. 9. Note that configurations not particularly mentioned below are assumed to be the same as the configurations described as the underlying technology or in the first embodiment.

In the example shown in FIG. 9, the virtual IP storage network unit 125 is divided into a virtual IP storage network unit 125A and a virtual IP storage network unit 125B. In this way, the telecom cloud 100 according to this embodiment may have a plurality of independent virtual IP storage network units 125. The virtual IP storage management unit 124 manages each of these multiple independent virtual IP storage network units 125.

An access analysis unit 126 is arranged within the intranet 4. The access analysis unit 126 acquires and analyzes access logs and latency information from the plurality of reverse proxies 113 included in the plurality of MEC hosts 110 constituting the MEC-CDN. The access log is a log when the UE 3 accesses the reverse proxy 113. For example, the access log includes information such as time, content, and information indicating whether or not a cache hit occurred for each user access. Latency information is information regarding the latency from when the reverse proxy 113 receives user access until it transmits the content. For example, the latency information may include the time when the UE3 sent the content request and the time when the content was received, and may be reported from the UE3 to the reverse proxy 113.

A MEC-CDN control unit 127 is arranged in the management host 120. The MEC-CDN control unit 127 is an example of a first processing unit that controls the network configuration of a plurality of cache servers that constitute the MEC-CDN. Specifically, the MEC-CDN control unit 127 divides the virtual IP storage network unit 125 or combines a plurality of virtual IP storage network units 125. In other words, the MEC-CDN control unit 127 divides virtual IP storage or combines divided virtual IP storage. According to this configuration, it is possible to dynamically change the configuration of the virtual IP storage network unit 125 (that is, the configuration of the virtual IP storage).

As an example, as shown in FIG. 9, MEC host 110A, MEC host 110B, and MEC host 110C are arranged on teleco cloud 100, and reverse proxies 113A to 113C and cache storage 114A to cache storage 114C are instantiated. shall be taken as a thing. Note that illustration of the MEC platform 111, MEC application 112, and virtual IP storage client 115 included in the MEC host 110B and the MEC host 110C is omitted. As shown in FIG. 9, the MEC-CDN control unit 127 may divide the virtual IP storage network unit 125 into a virtual IP storage network unit 125A and a virtual IP storage network unit 125B. Virtual IP storage network section 125A provides connectivity between reverse proxies 113A and 113B and cache storages 114A and 114B. The virtual IP storage network unit 125B provides connectivity between the reverse proxy 113C and the cache storage 114C. On the other hand, the MEC-CDN control unit 127 may combine the virtual IP storage network unit 125A and the virtual IP storage network unit 125B. The combined virtual IP storage network section 125 provides connectivity between the reverse proxies 113A, 113B, and 113C and the cache storages 114A, 114B, and 114C.

The MEC-CDN control unit 127 divides the virtual IP storage network unit 125 or divides the virtual IP storage network unit 125 or divides the virtual IP storage network unit 125 into multiple virtual IP storages, triggered by the fact that the index related to cache processing in the multiple cache servers that constitute the MEC-CDN no longer satisfies the service request. The storage network unit 125 is connected. The MEC-CDN control unit 127 may repeat dividing/combining the virtual IP storage network unit 125 until the service request is satisfied. With this configuration, it is possible to make the index regarding cache processing meet the service request again.

A service request is a request for an index related to cache processing. The index regarding cache processing may relate to at least one of cache hit rate and latency. According to this configuration, it is possible to optimize the configuration of the virtual IP storage from the viewpoint of at least one of cache hit rate and latency. Note that the service request may be set by the OSS/BSS 123. Then, the access analysis unit 126 may monitor whether the service request is satisfied.

Here, when a virtual IP storage including a large number of cache storages 114 is configured, although the cache hit rate improves, the latency worsens at the cost. Since the cache storages 114 are distributed along the network 1 of the carrier, the more cache storages 114 that make up the virtual IP storage, the more likely it is that long-distance communication across different GCs 13 will occur. be. On the other hand, when a virtual IP storage including a small number of cache storages 114 is configured, although latency is improved, the cache hit rate is degraded at the cost. From the above, it is desirable that a service request be set for both an index related to cache hit rate and an index related to latency. In that case, it becomes possible to optimize the balance between cache hit rate and latency.

The MEC-CDN control unit 127 may divide the virtual IP storage network unit 125 when the latency has worsened and the latency-related index no longer satisfies the service request. The more finely the virtual IP storage network section 125 is divided, the fewer the cache storages 114 that make up the virtual IP storage, and thus the latency is improved. On the other hand, the more virtual IP storage network sections 125 are combined, the more cache storages 114 that constitute the virtual IP storage increase, and thus the latency worsens. In this regard, with this configuration, it is possible to improve latency and satisfy service requests regarding latency.

On the other hand, the MEC-CDN control unit 127 may combine the plurality of virtual IP storage network units 125 when the cache hit rate deteriorates and the index regarding the cache hit rate no longer satisfies the service request. The finer the virtual IP storage network unit 125 is divided, the fewer the cache storages 114 that make up the virtual IP storage, the lower the cache hit rate and the shorter the remaining cache time. On the other hand, as the virtual IP storage network units 125 are combined, the number of cache storages 114 configuring the virtual IP storage increases, so the cache hit rate increases and the cache remaining time increases. In this regard, according to this configuration, it is possible to improve the cache hit rate and satisfy the service request regarding the cache hit rate.

After dividing the virtual IP storage network unit 125 or after combining multiple virtual IP storage network units 125, the MEC-CDN control unit 127 may maintain the divided or combined state until a predetermined period of time has elapsed. . That is, after dividing or combining the virtual IP storage network unit 125, the MEC-CDN control unit 127 does not divide the virtual IP storage network unit 125 until a predetermined period of time has elapsed even if the index related to cache processing does not satisfy the service request. and not combined. As an example, assume that the virtual IP storage network unit 125 is divided into a virtual IP storage network unit 125A and a virtual IP storage network unit 125B. Immediately after the division, access from the reverse proxies 113A and 113B to the content stored in the cache storage 114C results in a cache miss. Therefore, the cache hit rate in reverse proxies 113A and 113B will temporarily decrease. However, it is assumed that the temporary decrease in the cache hit rate will recover as time passes. In this regard, with this configuration, it is possible to confirm that the service request has been satisfied after the temporary drop in the cache hit rate has recovered. In other words, it is possible to prevent a situation where the configuration of the virtual IP storage network section 125 is repeatedly changed in response to a temporary decrease in the cache hit rate.

The MEC-CDN control unit 127 may change the settings of the MEC-CDN access control unit 122 in accordance with the division or combination of the virtual IP storage network unit 125. Specifically, the MEC-CDN control unit 127 controls the MEC-CDN so that user access to content is distributed to the reverse proxy 113 connected to the cache storage 114 storing the content via the virtual IP storage network unit 125. Change the settings of the CDN access control unit 122. As an example, the MEC-CDN access control unit may generate a list that associates content identification information with the reverse proxy 113 connected to the cache storage 114 that stores the content via the virtual IP storage network unit 125. 122 may be registered. According to this configuration, it is possible to suppress a decrease in the cache hit rate due to a change in the configuration of the virtual IP storage network unit 125.

(2) Processing FIG. 10 is a sequence diagram showing an example of the flow of virtual IP storage configuration control processing executed by the teleco cloud 100 according to the present embodiment. This sequence involves the OSS/BSS 123, access analysis unit 126, reverse proxy 113, MEC-CDN control unit 127, virtual IP storage management unit 124, virtual IP storage network unit 125, and MEC-CDN access control unit 122. . Note that the explanation of messages indicated by broken lines in this sequence may be omitted. The message is a response to the message sent and received in the previous stage, and includes processing results based on the message sent and received in the previous stage.

As shown in FIG. 10, first, the OSS/BSS 123 sets a service request to the access analysis unit 126 (step S302). For example, the OSS/BSS 123 sets, as a service request, a lower limit value C _L of cache hit rate and an upper limit value L _U of latency that are allowed as a service.

Next, the reverse proxy 113 transmits the access log and latency information to the access analysis unit 126 (step S304).

Next, the access analysis unit 126 determines whether the service request is satisfied based on the information collected from the reverse proxy 113 (step S306). For example, the access analysis unit 126 calculates the cache hit rate, latency, and jitter, and determines whether the following formula (1) and the following formula (2) hold true.

Here, s is the index of the MEC host 110. That is, A corresponding to the MEC host 110A, B corresponding to the MEC host 110B, or C corresponding to the MEC host 110C is substituted for s. t is time. Cr(s,t) is the cache hit rate of the cache server on the MEC host 110(s) at time t. Lr(s, t) is the latency of the cache server on MEC host 110(s) at time t. Jm(s, t) is the maximum jitter value of the cache server on the MEC host 110(s) at time t.

In the initial settings of the virtual IP storage, all cache storages 114 are collectively defined as one virtual IP storage. Therefore, if the load on the virtual IP storage network unit 125 increases due to factors such as an increase in the number of users of the MEC-CDN, the latency of each cache server may deteriorate.

If it is determined that the service request is not satisfied, the access analysis unit 126 transmits the determination result to the MEC-CDN control unit 127 (step S308). The determination result here includes information indicating the target cache server and the calculation results of Formula (1) and Formula (2).

Next, the MEC-CDN control unit 127 determines the network configuration of the virtual IP storage based on the determination result received from the access analysis unit 126 (step S310). As an example, the MEC-CDN control unit 127 determines to divide the virtual IP storage network unit 125 if the above formula (2) regarding latency is not satisfied. As another example, the MEC-CDN control unit 127 determines to combine the virtual IP storage network unit 125 when the above formula (1) regarding the cache hit rate is not satisfied. Here, the above formula (2) is not satisfied, and it has been decided to divide the virtual IP storage network unit 125 into the virtual IP storage network unit 125A and the virtual IP storage network unit 125B shown in FIG. shall be taken as a thing.

Next, the MEC-CDN control unit 127 transmits a configuration change request to the virtual IP storage management unit 124 (step S312). The configuration change request includes information indicating the network configuration of the virtual IP storage determined in step S310.

Next, upon receiving the configuration change request, the virtual IP storage management unit 124 transmits the received configuration change request to the virtual IP storage network unit 125 (step S314).

Next, the virtual IP storage network unit 125 changes the network configuration of the virtual IP storage based on the received configuration change request (step S316). Specifically, the virtual IP storage network unit 125 includes a virtual IP storage network unit 125A that provides connectivity to the cache storage 114A and the cache storage 114B, and a virtual IP storage network unit 125B that provides connectivity to the cache storage 114C. , is divided into two parts. As a result, the only virtual IP storage in the cache server on the MEC host 110C is the cache storage 114C on the MEC host 110C.

Then, the MEC-CDN control unit 127 requests the MEC-CDN access control unit 122 to change the user access control settings in accordance with the configuration change of the virtual IP storage network unit 125 (step S318). Specifically, the MEC-CDN control unit 127 controls the MEC-CDN so that user access to content is distributed to the reverse proxy 113 connected to the cache storage 114 storing the content via the virtual IP storage network unit 125. Change the settings of the CDN access control unit 122.

By repeating the process described above, it is expected that the configuration of the virtual IP storage network unit 125 will be dynamically changed, and in conjunction with the access control by the MEC-CDN access control unit 122, the service request will be satisfied. . However, the access analysis unit 126 may resume checking whether the service request is satisfied after a predetermined period of time has passed since the configuration of the virtual IP storage network unit 125 was changed. This is to suppress excessive reaction to a temporary decrease in the cache hit rate.

(3) Summary As explained above, according to this embodiment, the configuration of the virtual IP storage network section 125 is dynamically divided or combined, and the allocation of user access by the MEC-CDN access control section 122 is dynamically performed. Be changed. As a result, it is expected that the decrease in the cache hit rate of the MEC-CDN can be kept to a small scale while improving the latency.

<4. Supplement>
Although preferred embodiments of the present invention have been described above in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person with ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea stated in the claims. It is understood that these also naturally fall within the technical scope of the present invention.

Although the first embodiment described above describes an example in which the cache storage 114 is arranged in the MEC host 110, the present invention is not limited to such an example. The present invention is also applicable to a configuration in which the cache storage 114 is located at an arbitrary position on the telecom cloud 100 (for example, within the intranet 4).

In the first embodiment described above, an example in which a cache server is arranged in the MEC host 110 has been described, but the present invention is not limited to such an example. The present invention is also applicable to a configuration in which a reverse proxy 113 is placed in the MEC host 110 and a shared cache storage 114 is placed in an arbitrary position on the telecom cloud 100.

In the first embodiment described above, an example has been described in which user access control to the cache server is executed using DNS, but the present invention is not limited to such an example. User access control to the cache server may be performed according to other access control methods, such as changing the domain name of the access destination in advance or redirecting to another URL.

Note that the series of processes performed by each device described in this specification may be realized using software, hardware, or a combination of software and hardware. A program constituting the software is stored in advance, for example, in a recording medium (specifically, a computer-readable non-temporary storage medium) provided inside or outside each device. For example, each program is read into the RAM when executed by a computer that controls each device described in this specification, and is executed by a processing circuit such as a CPU. The recording medium is, for example, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, or the like. Furthermore, the above computer program may be distributed, for example, via a network, without using a recording medium. Further, the above-mentioned computer may be an application-specific integrated circuit such as an ASIC, a general-purpose processor that executes functions by loading a software program, or a computer on a server used for cloud computing. Furthermore, a series of processes performed by each device described in this specification may be distributed and processed by multiple computers.

Further, the processes described using flowcharts and sequence diagrams in this specification do not necessarily have to be executed in the illustrated order. Some processing steps may be performed in parallel. Also, additional processing steps may be employed or some processing steps may be omitted.

1 Telecommunication carrier network 2 Internet 3 UE
4 In-network network 5 5G network 11 Central DC
12 Regional DC
13 GC
14 B.S.
15 ISP
16 IX
17 DC
18 Cache server 19 Origin server 20 MEC
30 Cache server 100 Teleco cloud 110 MEC host 111 MEC platform 112 MEC application 113 Reverse proxy 114 Cache storage 115 Virtual IP storage client 120 Management host 121 MEC platform management section 122 MEC-CDN access control section 123 OSS/BSS
124 Virtual IP storage management unit 125 Virtual IP storage network unit 126 Access analysis unit 127 MEC-CDN control unit 130 Telecommunications carrier internal DNS

Claims (20)

a first processing unit that controls a network configuration of a plurality of cache servers that configure a MEC-CDN (Multi-access Edge Computing-enabled Contents Delivery Network) connected to a core network of a mobile communication network;
Equipped with
The cache server is
a reverse proxy that relays user access to content;
cache storage, which is a storage area that can temporarily store the content;
including;
the reverse proxy accesses the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage;
The first processing unit divides the virtual network or combines the plurality of virtual networks.
Control device. The first processing unit divides the virtual network or combines the plurality of virtual networks based on an index related to cache processing in the plurality of cache servers forming the MEC-CDN.
The control device according to claim 1. The first processing unit divides the virtual network or divides the plurality of virtual networks, triggered by the fact that an index related to cache processing in the plurality of cache servers constituting the MEC-CDN no longer satisfies a service request. combine,
The index related to cache processing in the plurality of cache servers forming the MEC-CDN is related to at least one of cache hit rate and latency.
The control device according to claim 2. The first processing unit divides the virtual network using the indicator regarding latency as a trigger that no longer satisfies the service request, and divides the virtual network into multiple groups using the indicator regarding cache hit rate as a trigger that no longer satisfies the service request. combining the virtual networks;
The control device according to claim 3. After dividing the virtual network or combining the plurality of virtual networks, the first processing unit maintains the divided or combined state until a predetermined time elapses.
The control device according to claim 1. The control device further includes a second processing unit that controls user access to content cached in the plurality of cache storages included in the plurality of cache servers configuring the MEC-CDN,
The first processing unit changes the settings of the second processing unit in accordance with the division or combination of the virtual network.
The control device according to any one of claims 1 to 4. a third processing unit that manages information regarding a plurality of cache servers configuring the MEC-CDN connected to the core network of the mobile communication network;
a fourth processing unit that adds a new cache server based on an index related to cache processing in the plurality of cache servers forming the MEC-CDN;
Equipped with
The third processing unit registers information regarding the newly added cache server when the new cache server is added.
Control device. The cache server is
a reverse proxy that relays user access to content;
a cache storage which is a storage area in which the content can be cached;
including;
The fourth processing unit instantiates the new cache server on the virtual machine as adding the new cache server.
The control device according to claim 7. The third processing unit manages a cache server placement list including information indicating the placement of the plurality of cache servers forming the MEC-CDN in an intra-operator network including the mobile communication network.
The control device according to claim 7. The third processing unit manages a storage management list that includes information on a plurality of cache storages included in a plurality of cache servers forming the MEC-CDN.
The control device according to claim 8. The third processing unit manages a content cache list that includes information on content cached in the plurality of cache storages included in the plurality of cache servers configuring the MEC-CDN.
The control device according to claim 8. The third processing unit manages a content placement list that includes information indicating cache positions of content in the plurality of cache storages included in the plurality of cache servers configuring the MEC-CDN.
The control device according to claim 8. The third processing unit transmits information indicating whether or not there is a valid cache for the content to the reverse proxy when the reverse proxy relays user access to the content.
The control device according to claim 8. The third processing unit is configured to transmit information indicating the cache storage caching the content when there is a valid cache for the content, and to transmit information indicating the cache storage caching the content via local breakout when there is no valid cache for the content. sending information indicating the cache storage where the retrieved content should be cached to the reverse proxy;
The control device according to claim 13. The third processing unit may process the content acquired via local breakout based on at least one of a distance from a user terminal that is a source of user access to the content and an available capacity of the cache storage. selecting said cache storage to cache;
The control device according to claim 14. the reverse proxy accesses the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage;
The control device according to claim 8 or any one of claims 11 to 15. A control method performed by a computer, comprising:
The control method includes:
controlling the network configuration of a plurality of cache servers configuring a MEC-CDN (Multi-access Edge Computing - enabled Contents Delivery Network) connected to a core network of a mobile communication network;
including;
The cache server is
a reverse proxy that relays user access to content;
cache storage, which is a storage area that can temporarily store the content;
including;
the reverse proxy accesses the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage;
Controlling the network configuration of the plurality of cache servers configuring the MEC-CDN includes dividing the virtual network or combining the plurality of virtual networks,
Control method. A control method performed by a computer, comprising:
The control method includes:
Managing information regarding a plurality of cache servers configuring an MEC-CDN connected to a core network of a mobile communication network;
Adding a new cache server based on an index related to cache processing in the plurality of cache servers forming the MEC-CDN;
including;
Managing information regarding the plurality of cache servers configuring the MEC-CDN includes, when a new cache server is added, registering information regarding the newly added cache server.
Control method. computer,
a first processing unit that controls a network configuration of a plurality of cache servers that configure a MEC-CDN (Multi-access Edge Computing-enabled Contents Delivery Network) connected to a core network of a mobile communication network;
function as
The cache server is
a reverse proxy that relays user access to content;
cache storage, which is a storage area that can temporarily store the content;
including;
the reverse proxy accesses the cache storage via a virtual network that provides connectivity between the reverse proxy and the cache storage;
The first processing unit divides the virtual network or combines the plurality of virtual networks.
program. computer,
a third processing unit that manages information regarding a plurality of cache servers configuring the MEC-CDN connected to the core network of the mobile communication network;
a fourth processing unit that adds a new cache server based on an index related to cache processing in the plurality of cache servers forming the MEC-CDN;
function as
The third processing unit registers information regarding the newly added cache server when the new cache server is added.
program.

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