A method of transferring data between a software defined network (SDN) and an information-centric network (ICN), wherein the method comprises receiving a request from an SDN node for a specific named content stored on an ICN, wherein the request is encapsulated in an Internet Protocol (IP) packet, decapsulating the IP packet using an IP protocol stack, parsing the request to obtain the name of the specific named content, finding a path to an ICN networking device hosting the specific named content using the name, and forwarding the packet to the ICN networking device over the path.
Modern communication and data networks comprise network nodes, such as routers, switches, bridges, and other devices that transport data through the network. Over the years, the telecommunication industry has made significant improvements to the network nodes to support an increasing number of protocols and specifications standardized by the Internet Engineering Task Force (IETF). Creating and coupling the complex network nodes to form networks that support and implement the various IETF standards (e.g., virtual private network requirements) has caused modern networks to become complex and difficult to manage. As a result, vendors and third-party operators seek to customize, optimize, and improve the performance of the interwoven web of network nodes.
A software defined network (SDN) is a network technology that addresses customization and optimization concerns within convoluted networks. SDNs may be Internet Protocol (IP) networks utilizing Transmission Control Protocol/Internet Protocol (TCP/IP) protocols. SDN decouples the data-forwarding capability, e.g., the data plane, from routing, resource, and other management functionality, e.g., the control plane, previously performed in the network nodes. Network nodes that support SDN, e.g., SDN compliant nodes, may be configured to implement the data plane functions, while the control plane functions may be provided by an SDN controller.
Information-centric networks (ICNs) have also emerged as a promising future Internet architecture, which go beyond the existing IP networks, e.g., SDNs, by shifting the communication model from the current host-to-host model, e.g., the Internet model, to the future information-object-to-object model, e.g., the ICN model. As known in the art, ICNs may be implemented on top of existing IP infrastructures e.g., by providing resource naming, ubiquitous caching, and corresponding transport services, or it may be implemented as a packet-level internetworking technology that would cause fundamental changes to Internet routing and forwarding. In ICN, information objects become the first class abstraction for the entities that exist in the communication model. Information objects may have names, and routing to and from such named objects may be based on their names. In ICN, IP addresses may be treated as a special type of name. Users who want to retrieve the information objects do not need to know where they are located, as distinct from current IP networks where users must specify the destination host‘s IP address when sending out such requests.
The fundamental paradigm shift that resulted by the change of the communication models from host-to-host to object-to-object requires a change to the current IP-based networks. More specifically, the existing network infrastructure may need to be abandoned in order to deploy ICN. Entirely abandoning the existing network infrastructure represents a waste of time, technology, and resources.
In one embodiment, the disclosure includes a method of transferring data between an SDN and an ICN, wherein the method comprises receiving a request for a specific named content stored on an ICN, wherein the request is encapsulated in an IP packet, decapsulating the IP packet using an IP protocol stack, parsing the request to obtain the name of the specific named content, finding a path to an ICN networking device hosting the specific named content using the name, and forwarding the request to the ICN networking device over the path.
In another embodiment, the disclosure includes an apparatus for transferring data between an SDN and an ICN, wherein the apparatus comprises a memory module, wherein the memory module comprises a protocol stack for an IP based network and a protocol stack for an ICN, a processor module coupled to the memory module, wherein the memory module contains instructions that when executed by the processor cause the apparatus to perform the following: receive a request for a specific named content, wherein the request is encapsulated in an IP packet, decapsulate the IP packet using the IP protocol stack, obtain the name of the specific named content, negotiate a path to an ICN networking device hosting the specific named content using the name, configure the request using the ICN protocol stack, and forward the configured request to the ICN networking device over the path.
In yet another embodiment, the disclosure includes a computer program product comprising computer executable instructions stored on a non-transitory medium that when executed by a processor cause the processor to perform the following: receive an IP packet on an SDN, wherein the IP packet comprises a request for a specific named content stored on an ICN, identify the specific named content using an IP protocol stack, communicate with an ICN node to identify a path to an ICN networking device hosting the specific named content, create a set of forwarding rules for bidirectional traffic forwarding along the identified path, and push the forwarding rules to the at least one SDN device.
It should be understood at the outset that although an illustrative implementation of one or more embodiments are provided below, the disclosed systems and/or methods may be implemented using any number of techniques, whether currently known or in existence. The disclosure should in no way be limited to the illustrative implementations, drawings, and techniques described below, including the exemplary designs and implementations illustrated and described herein, but may be modified within the scope of the appended claims along with their full scope of equivalents.
Disclosed herein are methods, apparatuses, and systems for permitting the transfer of data between one or more SDNs and one or more ICNs. In one embodiment, which may be referred to as a loosely coupled model, the process is carried out using one or more gateway nodes, which serve as interfaces to transfer data between the SDN(s) and ICN(s). These gateway nodes may be configured with dual protocol stacks for processing packets in order to pass data from one network to another according to the respective network‘s standards. Another embodiment, which may be referred to as a tightly coupled model, configures the SDN controller(s) to identify paths and forwarding rules for transmitting data between the SDN(s) and ICN(s). In one such tightly coupled embodiment, the ICN nodes are configured with dual protocol stacks to function as the primary packet processing devices for configuring data for transmission. In another such tightly coupled embodiment, all SDN nodes are configured with dual protocol stacks. In still another such tightly coupled embodiment, all ICN nodes and SDN nodes are configured with dual protocol stacks.
FIG. 1?is a schematic diagram of a system?100?comprising an SDN?102?and an ICN?112. In general, SDNs decouple network control from forwarding and are directly programmable, e.g., by separating the control plane from the data plane and implementing the control plane using software applications and a centralized traffic controller and/or network controller, which may make routing decisions and communicate these decisions to devices on the network. SDNs are well known in the art.
FIG. 1?comprises a central traffic controller or SDN controller?104. The SDN controller?104?may be configured to perform control path and/or control plane functionality, which may include routing and resource management. The SDN controller?104may communicate with, may monitor, and may control the underlying network components?108?and?110, as shown by the dashed lines. The underlying network components?108?and?110?may exchange data in the manner illustrated, as shown by the solid lines. Network components?108?and?110?may separately be any components configured to receive and/or transmit data through the data network, e.g., routers, switches, servers, etc. Network components?110?may be simple forwarding devices. The network components?108?may function as decision nodes. Decision nodes may possess a cache storing one or more provider addresses or an address at which a content host may be reached to provide specified content. The SDN controller?104?may make decisions on how to assign resources and route different application/information flows through the SDN?102, e.g., through network components?108?and/or?110. Upon receipt of a packet from an application, the decision node may check whether a cache entry contains one or more provider addresses associated with the data requested in the packet to which the packet may be routed. If so, the decision node may route the packet to a selected provider address. If not, the decision node may ask the SDN controller?104?for provider addresses and may update its cache upon receipt thereof. When a second decision node receives a packet from a first decision node, the second decision node may remove the packet header and deliver the packet to the application(s) using the original packet header address.
FIG. 1?further comprises an ICN?112?comprising ICN nodes?114. ICN?112?may provide information dissemination by routing names that identify content objects and services, rather than by location. This allows disassociation of services and resulting content objects from their location. An ICN may include a Forwarding Information Base (FIB), and a content store (CS). Generally, an ICN may work on two primitives: interest and data. An ICN-enabled device may look for the closest copy of content by multicasting the interest packets with the content name into the network. Contents may reside in any host at the producers end, or may be cached in CSs of the ICN routers?114. This caching feature may allow users to retrieve the same content without introducing replicated traffic into the network. As long as some users have retrieved the content, the content may be cached in the network and may be fetched by any number of users. ICNs are well known in the art.
In a system?100?comprising SDN?102?and ICN?112, those of skill in the art will readily perceive that SDN?102?and ICN?112cannot engage in bidirectional data exchange using present protocols, as illustrated by the broken line connecting SDN?102and ICN?112. System?100?represents the current state of the art, wherein ICNs are emerging adjacent to legacy SDNs. Thus, an end user?116?in communication with SDN?102?is presently unable to obtain data residing solely on ICN?112?using conventional approaches. Consequently, under conventional approaches, because the SDN and ICNs are not capable of bidirectional data exchange, existing SDN infrastructures, e.g., SDN?102, may need to be abandoned in order to fully deploy ICNs, e.g., ICN?112, and permit end users, e.g., end user?116, to obtain data from the ICN.
FIG. 2?is a schematic diagram of a system?200?showing a first embodiment for transferring data between an SDN?102?and an ICN?112. Except as otherwise noted, the components of?FIG. 2?are substantially the same as the corresponding components of?FIG. 1.?FIG. 2?further contains access points or gateway nodes?204. Gateway nodes?204?may be in communication with SDN?102, e.g., via SDN node?108, and may be in communication with ICN?112, e.g., via ICN nodes114, as depicted. Gateway nodes?204?may be configured with dual protocol stacks, an IP protocol stack for communicating with SDN?102?and an ICN protocol stack for communicating with ICN?112. As will be understood by those of skill in the art, SDN controller?104, SDN nodes?108?and/or?110, and/or ICN nodes?114?may be configured with dual protocol stacks in alternate embodiments as needed to carry out a system or method as disclosed herein. Initially, the SDN network components?108?and/or?110?may be pre-loaded with instructions comprising a set of forwarding rules instructing SDN network components?108?and/or?110?how to process packets received or bound for particular destinations or objects, e.g., specific clients, named objects, gateway nodes, or ICN servers, as discussed under?FIG. 6.
FIG. 3?is a protocol diagram for transmitting data in system?200?of?FIG. 2?from a user?116?through an SDN?102?to an ICN router?114?of an ICN?112. The components referenced in?FIG. 3?are the same as the corresponding components listed inFIG. 2. The process of?FIG. 3?may begin at?302?with a user?116?sending send a request containing an object‘s name encapsulated in an IP packet to an SDN router?110. The packet may utilize a pre-determined destination IP address that is dedicated for ICN use, e.g., an anycast IP address or an IP address handed out by the network provider when the client subscribes to or registers with the network. If SDN router?110?has forwarding rules for this packet, SDN router?110?may process the packet in accordance with the forwarding rules. If SDN router?110?does not have forwarding rules for this packet, at?304, SDN router?110?may send the packet to SDN controller?104. SDN controller?104?may choose one or more gateway nodes?204?to serve as the interface for transferring data between SDN?406?and ICN?112. At?306, SDN controller104?may set up or create forwarding rules for reaching the chosen gateway node?204?access point(s) and may push the forwarding rules to the sending SDN router?110. In some embodiments, additional network components?108?and/or?110?also receive the forwarding rules. Once the sending SDN router?110?is configured with the forwarding rules, at?308?the sending SDN router?110?may send the packet to gateway node?204. When gateway node?204?receives the IP packet, gateway node?204?may decapsulate the IP packet using the IP protocol stack, parse the packet to obtain the name of the specified named content, and may find the path to the ICN networking device hosting the specific named content, e.g., ICN router114. Once the path is identified, gateway node?204?may process the packet using the ICN protocol stack. At?310, gateway node?204?may forward the packet to the ICN networking device, e.g., ICN router?114. At?312, the requested specified named content may be sent from an ICN router?114?to gateway node?204. Gateway node?204?may receive the specified name content, may encapsulate the specified named content in an IP packet, and at?314?may forward the modified packet containing the specified named content to the user?116?via SDN router?110. Dashed line?316?represents any future communications between user?116?and ICN router?114?as enabled by the forwarding rules and the gateway node(s)?204.
FIG. 4?is a schematic diagram of a system?400?showing a second embodiment for transferring data between an SDN?102and an ICN?112. Except as otherwise noted, the components of?FIG. 4?are substantially the same as the corresponding components of?FIG. 1. For example, in?FIG. 4, SDN controller?104?is configured with dual protocol stacks: an IP protocol stack for communicating with SDN?102?and an ICN protocol stack for communicating with ICN?112. As will be understood by those of skill in the art, in another embodiment SDN network components?108?and/or?110, and/or ICN nodes?114?may alternately or additionally be configured with dual protocol stacks in this manner as needed to carry out a system or method as disclosed herein.?FIG. 4?further shows a data path between SDN controller?104?and ICN?112, e.g., via an ICN router114, as well as a data path between SDN router?108?and ICN router?114.
FIG. 5?is a protocol diagram for transmitting data in system?400?from a user?116?through an SDN?102?to an ICN router?114of an ICN?112. The components of?FIG. 5?may be the same as the corresponding components in?FIG. 4. At?502, a user?116may send a request comprising a specifically named content‘s name, encapsulated in an IP packet, to an SDN router?110. The packet may utilized a pre-determined destination IP address that is dedicated for ICN use, e.g., an anycast IP address or an IP address handed out by the network provider when the client subscribes to or registers with the network. SDN network components?108?and/or?110?may be pre-loaded with instructions comprising a set of forwarding rules instructing SDN network components?108?and/or?110?how to process packets received or bound for particular destinations or objects, e.g., specific clients, named contents and/or objects, gateway nodes, and/or ICN servers, as described further below underFIG. 6. If the SDN router?110?has forwarding rules for this packet, the SDN router?110?may process the packet in accordance with the forwarding rules. If the SDN router?110?does not have forwarding rules for this packet, at?504, the SDN router?110?may send the packet to the SDN controller?104. The SDN controller?104?may decapsulate the IP packet using the IP protocol stack and may parse the packet to obtain the name of the specified named content. At?506, the SDN controller?104?may negotiate a path to the ICN networking device hosting the specific named content, e.g., by communicating with the ICN‘s name directory at an ICN router?114?to look up possible ICN servers that can satisfy the request. At?508, the SDN controller?104?may set up or create forwarding rules for reaching the chosen access point(s), e.g., ICN router?114, and may push the rules to the SDN router?110. Once received, the SDN router?110?may be configured to forward packets to the ICN?112, e.g., at an ICN router?114, using the forwarding rules. At?510, the SDN router?110sends the packet to the ICN router?114. In one embodiment, the ICN router?114?may encapsulate the specified named content in an IP packet and at?512A may send the requested specified named content to the user?116?using the SDN?102. In another embodiment, at?512B, the ICN router?114?may send the requested specific named content to an SDN component, e.g., the SDN router?110, where the SDN router?110?may encapsulate the specified named content in an IP packet and forward the modified packet to the user?116. Dashed line?514?represents any future communications between user?116?and the ICN router?114?as enabled by the forwarding rules and the gateway node(s)?204.
FIG. 6?is a flowchart describing preconfiguring an SDN, e.g., SDN?102, for processing IP/ICN packets. At?602, the network may select an anycast IP address, or a particular IP address, as an entry IP address for the ICN. As will be understood by those of skill in the art, anycast may be a network addressing and routing methodology in which datagrams from a single sender are routed to the topologically nearest node in a group of potential receivers, though it may be sent to several nodes, all identified by the same destination address. Once an entry IP address is selected, any packet coming from or destined for the selected IP address may be treated as an ICN request. At?604, the deployment model may be selected, e.g., the deployment model of system?200?or system?400. In embodiments selecting the deployment model of system?200, at?606?the ICN gateway nodes?204?may also be configured. At?608, the SDN controller may push a set of forwarding rules to the network devices, e.g., instructing packets destined for the ICN entry address to be forwarded to one or more gateway nodes?204. The selection of which of the one or more gateway nodes?204?to which to forward packets may be dynamically determined by the load balancing policies, the proximity, or some other factor. At?610, the forwarding rules set up for specific clients/named objects/ICN gateways/ICN servers may be removed by an SDN controller when no packet matches the rules for a specific amount of time, when the communications defined by the rules have been torn down, or when the communications defined by the rules actively expired. In embodiments selecting the deployment model of system400, at?612?the SDN controllers may actively or passively participate in the control-plane decision process of ICN, e.g., by learning where named objects are and how to reach named objects. At?614, packets may be handed over to the SDN controller where delayed decisions, also referred to as lazy-binding decisions, may be made. At?610, the forwarding rules set up for specific clients/named objects/ICN gateways/ICN servers may be removed by an SDN controller when no packet matches the rules for a specific amount of time, when the communications defined by the rules have been torn down, or when the communications defined by the rules actively expired.
At least some of the features/methods described in the disclosure may be implemented in a network element. For instance, the features/methods of the disclosure may be implemented using hardware, firmware, and/or software installed to run on hardware. The network element may be any device that transports data through a network, e.g., a switch, router, bridge, server, client, etc.?FIG. 7?is a schematic diagram of an embodiment of a network element?700, which may be any device that transports and processes data through a network. For instance, the network element?700?may be gateway node?204, network components?108?and/or?110, ICN server?114, and/or SDN controller?104?in the SDN/ICN schemes described above.
The network element?700?may comprise one or more downstream ports or faces?710?coupled to a transceiver (Tx/Rx)?712, which may be transmitters, receivers, or combinations thereof. A Tx/Rx?712?may be coupled to a plurality of downstream ports?710?for transmitting and/or receiving frames from other nodes, a Tx/Rx?712?coupled to a plurality of upstream ports730?for transmitting and/or receiving frames from other nodes. A processor?725?may be coupled to the Tx/Rxs?712?to process the frames and/or determine the nodes to which to send frames. The processor?725?may comprise one or more multi-core processors and/or memory modules?722, which may function as data stores, buffers, etc. Processor?725?may be implemented as a general processor or may be part of one or more application specific integrated circuits (ASICs) and/or digital signal processors (DSPs). The downstream ports?710?and/or upstream ports?730?may contain electrical and/or optical transmitting and/or receiving components. Network element?700?may or may not be a routing component that makes routing decisions. The network element?700?may also comprise a programmable content forwarding plane block?728. The programmable content forwarding plane block?728?may be configured to implement content forwarding and processing functions, such as at an application layer or layer 3 (L3) in the Open Systems Interconnection (OSI) model, where the content may be forwarded based on content name or prefix and possibly other content related information that maps the content to network traffic. Such mapping information may be maintained in a content table?729?at the memory module?722. The programmable content forwarding plane block?728?may interpret user requests for content and accordingly fetch content, e.g., based on metadata and/or content name, from the network or other content routers and may store the content, e.g., temporarily, in the memory module?722. The programmable content forwarding plane block?728?may then forward the cached content to the user. The programmable content forwarding plane block?728?may be implemented using software, hardware, or both and may operate above the IP layer or layer 2 (L2) in the OSI model. The memory module?722may comprise a cache for temporarily storing content, e.g., a Random Access Memory (RAM). Additionally, the memory module?722?may comprise a long-term storage for storing content relatively longer, e.g., a Read Only Memory (ROM). For instance, the cache and the long-term storage may include Dynamic random-access memories (DRAMs), solid-state drives (SSDs), hard disks, or combinations thereof. Notably, the memory?722?may be used to house the dual protocol stacks for the ICN(s) and SDN(s).
SRC=https://www.google.com/patents/US20130332619
原文：http://www.cnblogs.com/coryxie/p/3866888.html