CN108200206A - A kind of ICN Seamless Mobile systems based on SDN frameworks - Google Patents

Abstract

The invention discloses a kind of ICN Seamless Mobile systems based on SDN frameworks, and the producer is corresponding with the mobile terminal that consumer carries to be denoted as first movement terminal and the second mobile terminal；When first movement terminal or the second mobile terminal are mobile and switch access point, edge switch corresponding to new access point can not match corresponding ID, so as to be transmitted to POF controllers, session management module and/or content managing module determine session information with POF controllers, and path planning issues flow table again；Later, first movement terminal matches mobile logo position according to the request received, and the content cached during loopback first movement terminal or the second mobile terminal mobile handoff, the second mobile terminal are handled the content received according to the serial number of content-data block.Seamless Mobile can be realized by the system, user is allow to restore the data lost due to mobile handoff process on demand.

Description

An ICN seamless mobile system based on SDN architecture

technical field

The invention relates to the field of communication technology, in particular to an ICN seamless mobile system based on SDN architecture.

Background technique

With the popularization of network applications in the field of production and life, the Internet has become an important cornerstone of economic and social development. The rise of broadband networks, especially the mobile Internet, has triggered explosive growth in users' demand for online content access. At the same time, the foreseeable 4G network used at this stage will be replaced by a more advanced 5G network. However, the initial design of the Internet is to support Host-to-Host, that is, host-to-host communication. When distributing and disseminating massive content, the IP end-to-end communication mode centered on the host address exposes problems in resource allocation and security. , controllability, especially the limitations of service quality. Due to the core position of content in Internet applications, the development of a new content-centric Internet architecture has become a general trend. Existing research refers to this type of architecture as Information-Centric Networking (ICN), as a new type of information-centric network. The center's network architecture, ICN's goal is to replace the existing IP network to meet people's growing network needs.

ICN is a new network structure that identifies the name of the data object rather than the location of the host. The related operations of the network are not related to the location identifier (IP address) but are bound to the name of the data object content. Contrary to the current TCP/IP model based on the sender, ICN transmission is based on the publish-subscribe information transfer process. Addressable interfaces that are not limited to networks. The sending of the data packet is triggered by the user request, and the user request is routed through the naming method, and the node with the cache will cache the passed content, and transfer the data through the reverse path of the corresponding interest request. In addition, since ICN is object-based, the security of information is only related to the content object itself, so the security of the ICN network can be separated from data integrity and confidentiality to achieve a new and more reasonable security model. In view of the above description, ICN is a new network structure that perfectly fits the future 5G network.

On the other hand, software-defined networking (Software-Defined Networking, SDN) separates the forwarding plane from the control plane. While giving the control plane greater flexibility, the forwarding plane can support more and more complex protocols. The current SDN standard OpenFlow1.X is still oriented to the IP protocol, so these studies can only stay in the imagination stage. The protocol-oblivious forwarding protocol (Protocol-Oblivious Forwarding, POF) is Huawei's extension to the OpenFlow protocol, and it is also a candidate component of the OpenFlow2.0 standard that is brewing. At present, the POF project already has physical equipment that can be used for actual network deployment, making it possible to study the 5G-ICN fusion system at the network layer with a realistic basis.

Among existing mobility support schemes:

1. The mechanism for discovering movement is not clearly given: some schemes default that the terminal can sense that it has moved when accessing or providing content, and actively exchange messages and data between the front and rear access points to achieve seamless mobility. However, due to mobility management Content access and content access belong to two levels, without direct communication, this default prerequisite does not hold.

2. There is no quantitative and reliable caching mechanism: In some solutions, when consumers fail to obtain content, they report to the control plane, and the control plane checks the routing path hop by hop, finds out the problem, and reconstructs and restarts the route. The time from failure to restart is uncertain, and there is no quantitative and reliable cache for the lost content during the period, so it is difficult to achieve seamless movement.

Contents of the invention

The purpose of the present invention is to provide an ICN seamless mobile system based on SDN architecture, which can realize seamless mobile and enable users to restore data lost due to the mobile handover process on demand.

The purpose of the present invention is achieved through the following technical solutions:

An ICN seamless mobile system based on SDN architecture, a POF controller, a session management module, a content management module and several edge switches set in the ICN core network control domain;

The mobile terminals carried by the producer and the consumer are correspondingly recorded as the first mobile terminal and the second mobile terminal; the first mobile terminal and the second mobile terminal respectively access the ICN core network control domain through the edge switch through the access point;

When the first mobile terminal or the second mobile terminal moves and switches the access point, the edge switch corresponding to the new access point cannot match the corresponding ID, so it forwards it to the POF controller, and the POF controller cooperates with the session management module and /or the content management module determines the session information, and re-plans the path to send the flow table; after that, the first mobile terminal matches the mobile identification bit according to the received request, and sends back the first mobile terminal or the second mobile terminal during the mobile handover process For the cached content, the second mobile terminal processes the received content according to the sequence number of the content data block.

It can be seen from the above-mentioned technical solution provided by the present invention that the access network and the core network, the control plane and the user plane are kept independent, relying on switches and controllers supporting the POF protocol, and based on the inherent communication mechanism of the ICN protocol, it can be found in the shortest time Whether the terminal moves when accessing or providing content; at the same time, quantitative and reliable seamless movement is realized through the periodic continuous cache of the producer.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For Those of ordinary skill in the art can also obtain other drawings based on these drawings on the premise of not paying creative work.

FIG. 1 is a schematic structural diagram of an ICN seamless mobile system based on an SDN architecture provided by an embodiment of the present invention;

FIG. 2 is a schematic diagram of an application scenario of an ICN seamless mobile system based on an SDN architecture provided by an embodiment of the present invention;

FIG. 3 is a flowchart of a second mobile terminal seamlessly acquiring content according to an embodiment of the present invention;

FIG. 4 is a flow chart of seamlessly providing content by a first terminal according to an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The embodiment of the present invention provides an ICN seamless mobility system based on the SDN architecture, which is a solution based on the POF controller and the IN routing of the switch, which can minimize the loss of access content during the communication process. In order to reduce the system load, seamless mobility should only be aimed at mobile terminals that are performing services, and this mechanism will not be triggered when terminals without services move. In order to realize this solution, in the embodiment of the present invention, it is considered that the ID of the content is self-generated and self-verified according to a unified rule, and the content is divided into data blocks for transmission, and numbered in sequence; create an ID for each service that needs to realize seamless mobility For the session, each maintains a buffer for the producer and the consumer (corresponding to the first mobile terminal and the second mobile terminal). From the beginning of the creation of the session service, the first mobile terminal slides and caches the sent data according to the specified period for the return Potentially lost content is used by the second mobile terminal to further process the received packets in the cache. In addition, during the session continuation phase, consumers periodically send requests to the control plane, and producers periodically send content publishing messages to the control plane. Set the content maintenance flow table in: POF-SW does not forward the content publishing message to the control plane every time after receiving the content release message, but forwards it to the control plane after a certain number of times or a certain period of time, and the control plane performs mobile perception based on this.

The schematic diagrams of the architecture and application scenarios of the above-mentioned system provided by the embodiments of the present invention are shown in FIGS. 1-2 respectively. The system can contain multiple ICN core network control domains, as well as a global system for global analysis.

Each ICN core network control domain includes POF controller (POF-Ctrl), session management module (SM), content management module (CM) and several edge switches.

The functions of each device in the above system are as follows: GNCAR realizes the domain resolution of the global object (only managed to the domain level); the content management module (CM) controls the content management and address resolution in the domain (accurate to the switch port); POF controller (POF -Ctrl) for path planning, topology management, and delivery of flow tables; the session management module (SM) controls session management in the domain; the edge switch forwards messages from access devices.

The interfaces and parameters involved in the above system are as follows: 1. Three types of messages: content release, request content (Interest packet), and return data (both including content ID, sender ID, switch ID and port). 2. Interface protocol: 1) Consumer vs SW; 2) SW vs Ctrl; 3) Ctrl vs SM; 4) SM vs CM; 5) CM vs GNCAR; 6) SW vs Producer.

In the embodiment of the present invention, the corresponding mobile terminals carried by the producer and the consumer are recorded as the first mobile terminal and the second mobile terminal; The switch POF-SW) is connected to the ICN core network control domain. The access point may be a WIFI access point or a base station or other types of access points.

In the embodiment of the present invention, when the first mobile terminal or the second mobile terminal moves and switches the access point, the edge switch corresponding to the new access point cannot match the corresponding ID, so the ID is forwarded to the POF controller, which is controlled by the POF The device cooperates with the session management module and/or the content management module to determine the session information, and re-plans the path to send the flow table; after that, the first mobile terminal matches the mobile identification bit according to the received request, and sends back the first mobile terminal or the second The mobile terminal moves the cached content during the switching process, and the second mobile terminal processes the received content according to the sequence number of the content data block.

The above process is actually divided into two situations:

1. The second mobile terminal seamlessly acquires content while moving

When the second mobile terminal carried by the consumer moves and switches access points, the process of seamlessly acquiring content is as follows:

After the second mobile terminal moves and switches the access point, the edge switch corresponding to the new access point cannot match the content ID of the Interest packet sent by the second mobile terminal, thereby forwarding the Interest packet to the POF controller;

The POF controller is identified as a conversational service, and queries the session management module; the session management module feeds back the session information of the conversational service to the controller; the session information includes: ID and address of the first mobile terminal; the POF controller according to After receiving the session information, re-plan the path and send the flow table, and set the mobile identification bit in the interest packet and forward it to the corresponding edge switch; the edge switch forwards the interest packet according to the flow table; the first mobile terminal according to the received interest packet to match the mobile identification bit, and send back the content cached during the mobile switching process of the second mobile terminal, and then send back the subsequent content; the second mobile terminal processes the received content according to the sequence number of the content data block.

2. The first mobile terminal seamlessly provides content while moving.

When the first mobile terminal carried by the producer moves and switches access points, the process of providing content seamlessly is as follows:

After the first mobile terminal moves and switches the access point, the first mobile terminal publishes the content, and the edge switch corresponding to the new access point cannot match the content ID, thus forwarding it to the POF controller;

After the POF controller recognizes that the content is published, it transfers it to the content management module; the content management module queries the content entry and finds that the content is associated with a session, then queries the session management module; the session information queried by the session management module is transmitted to the POF through the content management module controller; the POF controller re-plans the path to send the flow table according to the received session information, and constructs an interest packet related to the session, sets the mobile identification bit in the interest packet and forwards it to the corresponding edge switch; the edge switch follows the The flow table forwards the interest packet; the first mobile terminal matches the mobile identification bit according to the received interest packet, and returns the content cached during the mobile switching process of the first mobile terminal, and then returns the subsequent content; the second mobile terminal according to the content data The sequence number of the block to process the received content.

As mentioned above, in order to reduce the system load, seamless mobility is only for the first mobile terminal and the second mobile terminal that are executing services; create a session for each service that needs to realize seamless mobility, and for the first mobile terminal and the second mobile terminal Each of the two mobile terminals maintains a buffer; the first mobile terminal slides and caches sent content at a specified period from the beginning of the establishment of the session service.

The above are the main solutions for realizing seamless mobility of the system provided by the embodiment of the present invention. For ease of understanding, the following will introduce again in combination with the main flow of the system.

The main process of the system is divided into four parts: the producer releases content through the first mobile terminal; the consumer requests content through the second mobile terminal to establish a new session; the consumer seamlessly obtains the content when moving with the second mobile terminal; The content is provided seamlessly while the first mobile terminal is moving.

1. The producer publishes content through the first mobile terminal.

Producers are required to periodically publish content via the first mobile terminal to keep content updated and accessible. The specific implementation is as follows:

1) The first mobile terminal publishes content to its attached access point, which is forwarded by the access point to the corresponding edge switch (POF-SW) for flow table matching.

2) If the matching is successful, the content is transmitted according to the rules of the flow table; if the matching content ID fails, it is forwarded to the POF controller.

3) The POF controller forwards the content to the content management module; if the content is received for the first time, the content management module creates a content entry, sends a content publishing success message to the POF controller, and requests the POF controller to make a content maintenance flow table, and Communicate with the global system, and register the ICN core network control domain where the content is located in the global system; otherwise, the content management module maintains the status of the content live (that is, the content is valid);

4) After that, the controller sends the content maintenance flow table to the edge switch;

5) The first mobile terminal periodically and repeatedly publishes the content message, matches the content maintenance flow table in the edge switch, and republishes the content to keep the content live state, if the content management module does not receive the content message within a certain period of time , the corresponding content entry is deleted.

2. The consumer requests content through the second mobile terminal to establish a new session

Consumers should issue requests periodically through the second mobile terminal during the duration of the session to maintain the continuity of content access. The specific implementation is as follows:

1) The second mobile terminal issues a request and sends an Interest packet to the access point it is attached to, and the Interest packet is sent to the corresponding edge switch for matching.

2) When requesting content for the first time, the edge switch fails to match the content ID and forwards it to the POF controller.

3) The POF controller judges whether the service is a session service, and if so, forwards it to the session management module.

4) The session management module requests content address resolution from the content management module, and the content management module queries the content address and returns the content address to the session management module.

5) The session management module establishes a new session entry and feeds back the session information to the POF controller, and submits the session information to the content management module at the same time, and the content management module associates the corresponding content with the session; meanwhile, the session management module also registers the session information to the global system In order to realize cross-domain query later.

6) The POF controller plans the path according to the session information and makes an ICN protocol flow table to implement ICN routing, sends the ICN protocol flow table to the edge switch and forwards the request interest packet downward; finally the second mobile terminal successfully obtains the ICN protocol flow table from the first mobile terminal required content.

3. The consumer seamlessly obtains the content while carrying the second mobile terminal on the move.

Assuming that after the consumer moves with the second mobile terminal, the edge switch to access changes from SW to SW2, as shown in Figure 3, the main process is as follows:

1) After the second mobile terminal moves and switches the access point, it sends an Interest packet.

2) The new access switch SW2 fails to match the content ID, and SW2 forwards the Interest packet to the POF controller.

3) The POF controller recognizes it as a conversational service, and inquires from the conference management module.

4) The session management module feeds back the session information of the session service, such as producer ID and address, to the POF controller.

5) The POF controller re-plans the route delivery flow table.

6) The POF controller sets the mobile identification bit in the Interest packet and forwards it downward to SW2.

7) SW2 forwards the Interest packet according to the flow table.

8) After receiving the Interest packet, the first mobile terminal matches the mobile identification bit, first sends back the cached content, and then sends back the subsequent content.

9) The second mobile terminal performs processing according to the sequence number of the content data block to complete seamless movement.

4. The producer seamlessly provides content when moving with the first mobile terminal.

Assuming that after the producer moves with the first mobile terminal, the edge switch connected changes from SW to SW2, as shown in Figure 4, the main process is as follows:

1) The first mobile terminal moves to switch the access point and publishes content.

2) The new access switch SW2 fails to match the ID, and forwards it to the POF controller.

3) The POF controller recognizes the published content and transfers it to the content management module.

4) The content management module queries the content item and finds that the content is associated with a session, and queries the session management module.

5) The session management module feeds back the session information of the session service to the content management module.

6) The content management module feeds back the session information to the POF controller.

7) The POF controller re-plans the path delivery flow table, constructs a session-related interest packet, sets the mobile identification bit in the interest packet, and forwards it downward.

8) SW2 forwards the Interest packet according to the flow table.

9) After receiving the Interest packet, the first mobile terminal matches the mobile identification bit and sends back the cached content.

10) The second mobile terminal performs processing according to the sequence number of the content data block to complete the seamless movement.

The above scheme of the embodiment of the present invention, compared with the prior art, mainly has the following beneficial effects:

1. The access network is independent from the core network, control plane and user plane, relying on switches and controllers that support the POF protocol, based on the inherent communication mechanism of the ICN protocol, to find out whether the terminal moves when accessing or providing content in the shortest time .

2. The producer realizes quantitative and reliable seamless movement through the periodic continuous buffering of the first mobile terminal.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person familiar with the technical field can easily conceive of changes or changes within the technical scope disclosed in the present invention. Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (6)

1. a kind of ICN Seamless Mobile systems based on SDN frameworks, which is characterized in that be set in ICN core net control domains POF controllers, session management module, content managing module and several edge switch；

The producer is corresponding with the mobile terminal that consumer carries to be denoted as first movement terminal and the second mobile terminal；First movement Terminal accesses ICN core net control domains each by access point with the second mobile terminal through edge switch；

When first movement terminal or the second mobile terminal are mobile and switch access point, the edge corresponding to new access point is handed over Corresponding ID can not be matched by changing planes, so as to be transmitted to POF controllers, session management module and/or content with POF controllers Management module determines session information, and path planning issues flow table again；Later, first movement terminal is according to the request received Match mobile logo position, and the content cached during loopback first movement terminal or the second mobile terminal mobile handoff, Second mobile terminal is handled the content received according to the serial number of content-data block.

2. a kind of ICN Seamless Mobile systems based on SDN frameworks according to claim 1, which is characterized in that work as consumer The second mobile terminal carried is mobile and when switching access point, the seamless process for obtaining content is as follows：

Second mobile terminal is mobile and after switching access point, and the edge switch corresponding to new access point can not match the second shifting The content ID of interest packet transmitted by dynamic terminal, so as to which interest packet is transmitted to POF controllers；

POF controllers are identified as conversational service, are inquired to session management module；Session management module is by the conversational service Session information feeds back to controller；The session information includes：The ID of first movement terminal and address；POF controllers are according to connecing Receiving session information, path planning issues flow table again, and put in interest packet mobile logo position be transmitted to downwards it is corresponding Edge switch；Edge switch forwards interest packet according to flow table；First movement terminal is matched according to the interest packet received Mobile logo position, and the content cached during the second mobile terminal of loopback mobile handoff, the then subsequent content of loopback again；The Two mobile terminals are handled the content received according to the serial number of content-data block.

3. a kind of ICN Seamless Mobile systems based on SDN frameworks according to claim 1, which is characterized in that work as the producer The first movement terminal of carrying is mobile and when switching access point, the seamless process for providing content is as follows：

First movement terminal is mobile and after switching access point, first movement terminal publication content, the side corresponding to new access point Edge interchanger can not matching content ID, so as to be transmitted to POF controllers；

After POF controllers are identified as publication content, it is given to content managing module；Content managing module inquiry content item is found should Content correlating sessions are then inquired to session management module；The session information that session management module inquires is through Content Management mould Block is transferred to POF controllers；According to session information is received, path planning issues flow table, and construct one to POF controllers again Interest packet associated with the session puts mobile logo position in interest packet and is transmitted to corresponding edge switch downwards；It hands at edge It changes planes and forwards interest packet according to flow table；First movement terminal matches mobile logo position, and loopback according to the interest packet received The content cached during first movement terminal mobile handoff, the then subsequent content of loopback again；Second mobile terminal is in The serial number for holding data block handles the content received.

4. according to a kind of ICN Seamless Mobile systems based on SDN frameworks of claim 1-3 any one of them, which is characterized in that Seamless Mobile is only for the first movement terminal and the second mobile terminal of the business that is carrying out；

One session of service creation of realization Seamless Mobile is needed to each, for first movement terminal and the second mobile terminal Respectively safeguard a buffering area；First movement terminal at the beginning of establishment, has just sent out content from session service by specified period slip buffer.

5. according to a kind of ICN Seamless Mobile systems based on SDN frameworks of claim 1-3 any one of them, which is characterized in that The process of first movement terminal publication content is as follows：

The access point publication content that first movement terminal is adhered to it, is forwarded to corresponding edge switch by access point, carries out Flow table matches；

If successful match, content transmission is carried out by flow table rule；If matching content ID fails, POF controllers are forwarded it to；

Content is transmitted to content managing module by POF controllers；If receiving the content for the first time, then in content managing module establishment Hold entry, content publication success message is sent to POF controllers, and ask POF controllers making content maintenance flow table, and with Global system communicates, and the ICN core net control domains where the content are registered in global system；Otherwise, Content Management mould Block keeps the state of content live；

Later, controller issues content and maintains in flow table to edge switch；

First movement terminal periodic repeats publication content-message, and matching content maintains flow table in edge switch, redistributes Content is to keep the state of content live, if content managing module does not receive the message of the content in a certain period of time, Delete corresponding content item.

6. according to a kind of ICN Seamless Mobile systems based on SDN frameworks of claim 1-3 any one of them, which is characterized in that The process that second mobile terminal request content establishes new session is as follows：

Second mobile terminal posting request, the access point adhered to it send interest packet, and interest coating is sent to corresponding side It is matched in edge interchanger；

For the first time during request content, edge switch matching content ID failures are forwarded to POF controllers；

POF controllers judge whether the business is conversational service, if so, being transmitted to session management module；

Session management module is to content managing module request content address resolution, content managing module inquiry content address and by Hold address and return to session management module；

Session management module establishes new session entry and to POF controller feeding back conversation information, while to content managing module Session information is submitted, content managing module is associated with corresponding content and session；Meanwhile session management module is also stepped on to global system Remember session information；

POF controllers are according to session information path planning and make ICN agreement flow tables, ICN routings realized, to edge switch Issue ICN agreements flow table and the interest packet of forwarding request downwards；Final second mobile terminal is successfully obtained from first movement terminal Required content.