CN105577537A - A multi-path forwarding method and system for an information center network based on historical records - Google Patents

Abstract

The present invention provides a multi-path forwarding method of an information center network based on historical records, comprising: after the first ICN node receives the interest packet sent by the second ICN node, it judges whether there is a name of the interest packet in the preset PIT table; if No, judge whether there is the name of the interest packet in the preset HRL table; if so, forward the interest packet from the destination port to the third ICN node, and update the preset PIT table; the destination port is the receiving port corresponding to the interest packet name stored in the HRL table. In the PIT table and the HRL table, there are the name of the interest packet or data packet, the receiving port of the interest packet or data packet, the receiving time, and the survival time of the record. The present invention guides the subsequent forwarding request by predicting the content of the cache of the neighbor node, and improves the utilization rate of the cache. A forwarding system is also provided.

Description

A multi-path forwarding method and system for an information center network based on historical records

technical field

The invention relates to a multi-path forwarding method and system of an information center network based on historical records.

Background technique

The Internet based on the TCIP/IP architecture has experienced decades of development, and it is relatively stable while constantly adapting to new technologies emerging from the upper and lower layers. However, the emergence of various new applications in turn drives the Internet towards an information-centric direction, implying a new communication model based on information delivery, caching, and real-time processing, such as differentiated web services, cloud computing, social network etc. Most of the existing content delivery solutions are overlaid on top of the IP protocol, such as the existing CDNs structure, but it has been debated due to its inefficiency in service assurance and resource utilization. However, unlike the existing point-to-point communication, the academic community has proposed a series of Information Centric Network (ICN) architectures. Although they are different in naming methods and allocation of data block sizes, they are Both support name-based network layer protocols. The ICN architecture advocates name-based communication, which is driven by the client and implemented by name-based routing, and is forwarded in a single-path or multi-path manner. Of course it also supports ubiquitous web caching.

Multi-path forwarding technology can adjust the load of each link, improve the utilization rate of cache, and can effectively reduce the impact of link failure and network congestion. The multipath technique in the ICN architecture is more challenging than that of TCP/IP. First of all, TCP/IP is a connection-oriented congestion control method, and the source executes the congestion control algorithm on the pre-calculated static path; however, in ICN, in addition to the client, the intermediate node can also make real-time forwarding decisions . Secondly, since each node in ICN has a cache, the interest packet sent by the client can be satisfied not only at the source end, but also at the intermediate cache node, so that the round-trip delay of the network from the perspective of the client is comparatively A large fluctuation range will lead to frequent changes in the window and unnecessary data retransmissions. Finally, because the nodes of the network have a cache function, corresponding storage strategies will be implemented for the forwarded data packets. In ICN, the multi-path forwarding of requests will affect the efficiency of network caching. For example, the same request may be in the The intermediate node is satisfied, and the remote access may be obtained along another path. In contrast, the cache replacement of the latter is more frequent, resulting in higher network redundancy.

A typical traditional multi-path forwarding scheme is a random forwarding method, which we call Random. Specifically, as shown in Figure 1, it is assumed that an ICN node R1 has three optional next-hop nodes {R2, R3, R4}, all of which can reach the server, and the corresponding egress is {f1, f2, f3}. When R1 receives a request whose name is prefixed with "/a", according to the random strategy, R1 will randomly select an exit from the three exits of the reachable content "/a" server. If the selected exit is f3, Then forward the request from the f3 port.

Carofiglio et al. proposed a congestion control algorithm that combines the characteristics of ICN, which we call the fib-weight method. In this method, the ICN node adds a weight w to each prefix exit of the FIB. When an Interest packet needs to be forwarded, the ICN node performs a weighted random selection according to the weight of the optional exit in the FIB, and then forwards the Interest packet. .

The weight w of the exit is related to the average number of pending interest packets of each port of the ICN node (the pending interest packet is an interest packet that is forwarded by the node but has not received the data packet corresponding to the interest packet), assuming that the ICN node every The average number of pending interest packets of each port is avg_PI. When a data packet or an interest packet is received, the average number of pending interest packets is updated, and the corresponding weight is also updated.

avg_PI(face, prefix) = α·avg_PI+(1-α)·I(face, prefix),

w(face, prefix)=1/avg_PI(face, prefix),

Among them, α is a coefficient, I(face, prefix) is the number of interest packets with the prefix prefix received by the interface face of the ICN node within a period of time, avg_PI is the average number of pending request interest packets of each interface of the ICN node, and the total The number of pending interest packets, that is, the sum of the number of interfaces in the entry records of each prefix can be obtained from the PIT of the ICN node, avg_PI(face, prefix) is the interest of the prefix of the prefix of the interface face of the ICN node after the update The number of packets, w(face, prefix) is the weight value of the interface face of the ICN node for the prefix prefix.

In this way, the greater the average number of requests for an exit, the more data packets will be returned from the exit in the future. In short, the exit will be busy and the possibility of congestion will be higher. is large, and the weight of the exit is inversely proportional to the number of average pending requests, then the weight of the exit will be relatively small.

Referring to Figure 2, assuming that the prefix of an ICN node is "/a", the weights of the three optional outlets {f1, f2, f3} are respectively {w1, w2, w3}, and the interest packet with the prefix "/a" is forwarded When requesting, a weighted random selection algorithm will be carried out according to the weight of each outlet. The probability of being selected with a large weight is also high, and the probability of being selected with a small weight is relatively small. Therefore, it is avoided to choose the exit that will be relatively busy in the future, and the load balance is achieved, and the possible congestion of the network is avoided.

The above Random strategy and Fib-weight strategy have the following disadvantages:

The Random strategy is more general, and it is relatively simple to implement. It can balance the load to a certain extent and avoid network congestion. However, this strategy is random forwarding on multiple paths, without considering the characteristics of ICN itself, and has no impact on the future of the network. Predicting the possible states may easily lead to unbalanced load of each link and cannot be improved.

The Fib-weight strategy takes the number of pending interest packets associated with each exit as a consideration. The larger the number of pending interest packets, the more data packets will be returned in the future. However, in multipath forwarding, this strategy is only for forwarding, without considering the cache situation of the network, or unable to perceive the cache situation of neighbors. For example, in Figure 2, if R1 at this time To forward a request with the prefix "/a", and the exit selected according to the weight is f2, but R2 has the content corresponding to the prefix "/a" in the cache due to the previous historical request, but there is no content in R3, so R3 can only Then continue to forward to the server according to your own forwarding strategy, and cannot use the cache on R2. In this way, the utilization rate of network resources is reduced, and user experience is also reduced.

Contents of the invention

The present invention provides a multi-path forwarding method and system of an information center network based on historical records, which can guide subsequent forwarding requests (that is, interest packets) by predicting the content cached by neighbor nodes, so that the cache utilization rate can be improved, and at the same time balance Link load reduces network congestion.

In a first aspect, the present invention provides a multi-path forwarding method based on historical records of an information center network. The ICN architecture includes a plurality of nodes, and the method includes:

The first ICN node in the ICN architecture receives the Interest packet sent by the second ICN node, and the Interest packet includes the name of the Interest packet;

Judging whether there is the name of the interest packet in the preset PIT table; the PIT table includes a plurality of PIT records, and each PIT record includes: the name of the pending interest packet, the name of the pending interest packet corresponding to the name Receive a port list and the lifetime of the PIT record, the pending Interest packet is an Interest packet that has been forwarded by the first ICN node but has not received a data packet corresponding to the Interest packet;

If not, it is judged whether there is the name of the interest packet in the preset history record table; multiple history records are included in the preset history record table, wherein each history record includes: the first ICN node receives The name of the received data packet, the receiving port of the data packet, the receiving time of the data packet and the survival time of the record;

If so, forward the interest packet from the destination port to the third ICN node, and update the preset PIT table with the name of the interest packet and the receiving port that received the interest packet; the destination port is The receiving port corresponding to the name of the Interest packet stored in the preset history record table.

Further, after judging whether there is the name of the interest packet in the preset history record table, the method further includes:

If not, then judge whether there is a name prefix matching the name of the interest packet in the preset FIB table; multiple FIB records are included in the FIB table, wherein each FIB record includes: name prefix, and the The port corresponding to the name prefix, and the weight value information of the port;

If so, according to the weight value information of each port in the FIB record to which the name prefix belongs, forward the interest packet to the third ICN node, and send the name of the interest packet and the receipt of the interest packet Ports are stored into the PIT table.

Further, after judging whether there is the name of the interest packet in the preset PIT table, the method also includes:

If yes, update the receiving port list corresponding to the name of the Interest packet in the PIT table with the receiving port of the Interest packet.

Further, before the first ICN node in the ICN architecture receives the Interest packet sent by the second ICN node, the method further includes:

Create a historical record table, including a plurality of historical records in the historical record table, wherein each historical record includes: the name of the data packet received by the ICN node, the receiving port of the data packet, the receiving time of the data packet and The lifetime of this record.

Further, after forwarding the interest packet from the destination port to the third ICN node, the method further includes:

Receiving a data packet; the data packet includes the name of the data packet;

judging whether the name of the data packet exists in the preset PIT table according to the name of the data packet;

If so, the data packet is forwarded from the destination return port, and the PIT record corresponding to the name of the data packet is deleted in the preset PIT table;

Judging whether to cache the data packet according to the preset caching rules, and judging whether to store the name of the data packet, the receiving port, the receiving time and the survival time of the record as a historical record in the data packet according to the preset storage rules In the preset history table mentioned above;

The destination return ports are all receiving ports corresponding to the names recorded in the preset PIT table.

Preferably, judging whether to cache the data packets according to preset caching rules includes:

judging whether the size of the data packet is less than or equal to the remaining cache space of the first ICN node;

If not, then determine whether the popularity of the name of the data package is greater than or equal to a preset popularity threshold;

If it is greater than or equal to, it is judged whether the popularity of the name of each data packet cached in the first ICN node is less than the preset popularity threshold;

If less, then judge whether the sum of the capacity of the remaining cache space of the replaceable data packet and the first ICN node is greater than or equal to the size of the data packet; the replaceable data packet is cached in the ICN node, A data packet whose name popularity is less than the preset popularity threshold;

If greater than or equal to, replace the replaceable data packet with the data packet.

Preferably, according to the preset storage rules, it is judged whether to store the name of the data packet, the receiving port, the receiving time and the survival time of the record as a historical record in the preset historical record table, including:

calculating and sorting the popularity of the names of the data packages stored in the preset history table;

Judging whether the popularity order of the name of the data package is less than or equal to a preset value;

If it is less than or equal to, the name of the data packet, the receiving port, the receiving time and the survival time of the record are stored as a historical record in the preset historical record table.

Further, after judging whether there is the name of the data packet in the preset PIT table according to the name of the data packet, the method further includes:

If not, the data packet is discarded.

In the second aspect, the present invention also provides a multi-path forwarding system of an information center network based on historical records, said system comprising:

A receiving unit, the first ICN node in the ICN architecture receives the Interest packet sent by the second ICN node, and the Interest packet includes the name of the Interest packet;

The first judging unit judges whether there is the name of the interest packet in the preset PIT table; the PIT table includes a plurality of PIT records, and each PIT record includes: the name of the pending interest packet, corresponding to the name The receiving port list of the pending Interest packet and the survival time of the PIT record, the pending Interest packet is an Interest packet that has been forwarded by the first ICN node but has not yet received a data packet corresponding to the Interest packet;

The second judging unit, if not, judges whether there is the name of the interest packet in the preset history record table; multiple history records are included in the preset history record table, wherein each history record includes: the The name of the data packet received by the first ICN node, the receiving port of the data packet, the receiving time of the data packet and the survival time of the record;

The first forwarding unit, if any, forwards the interest packet from the destination port to the third ICN node, and updates the preset PIT table with the name of the interest packet and the receiving port that receives the interest packet; The destination port is the receiving port stored in the preset history table and corresponding to the name of the Interest packet.

Further, the system also includes:

The third judging unit, when there is no name of the interest packet in the preset history record table, then judge whether there is a name prefix matching the name of the interest packet in the preset FIB table; the FIB table includes multiple A FIB record, wherein each FIB record includes: a name prefix, a port corresponding to the name prefix, and weight value information of the port;

The second forwarding unit, if any, forwards the interest packet to the third ICN node according to the weight value information of each port in the FIB record to which the name prefix belongs, and sends the name of the interest packet and the received The receiving port of the Interest packet is stored in the PIT table.

It can be seen from the above technical solution that the present invention predicts the contents of the neighbor node cache according to the historical records to guide subsequent forwarding requests (that is, interest packets), so that the cache utilization rate is improved, and the link load is balanced at the same time, reducing network congestion. , which reduces the service time requested by the user and improves the user experience.

Description of drawings

FIG. 1 is a schematic diagram of an ICN framework applying a Random strategy in the prior art;

FIG. 2 is a schematic diagram of an ICN framework applying a fib-weight strategy in the prior art;

FIG. 3 is a flow chart of a multipath forwarding method for an information center network based on historical records provided by an embodiment of the present invention;

FIG. 4 is a flow chart after receiving data packets provided by an embodiment of the present invention;

Fig. 5 is a kind of specific flowchart of judging whether to cache the data packet according to the preset caching rules in step S405 in Fig. 4;

Fig. 6 is a kind of ICN topology diagram of the multi-path forwarding method of the information center network based on historical records of the application of the present invention;

Fig. 7 and Fig. 8 are the simulation result graphs adopting Random strategy, fib-weight strategy and CAMF strategy;

FIG. 9 is a functional block diagram of a multi-path forwarding system of an information center network based on historical records according to an embodiment of the present invention.

Explanation of reference signs

Receiving unit 901 First judging unit 902 Second judging unit 903 First forwarding unit 904

detailed description

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

Fig. 3 shows a flowchart of a multi-path forwarding method for an information center network based on historical records provided by an embodiment of the present invention.

As shown in FIG. 3, a multipath forwarding method of an information center network based on historical records in this embodiment includes a plurality of nodes in the ICN architecture, and the method includes:

S301. The first ICN node in the ICN architecture receives an Interest packet sent by a second ICN node, and the Interest packet includes a name of the Interest packet;

S302. Determine whether the name of the interest packet exists in the preset PIT table; the PIT table includes a plurality of PIT records, and each PIT record includes: the name of the pending interest packet, and the pending interest corresponding to the name The receiving port list of the packet and the survival time of the PIT record, the pending interest packet is an interest packet that has been forwarded by the first ICN node but has not received a data packet corresponding to the interest packet; if any, then Execute step S303, otherwise execute step S304;

What needs to be explained here is that: the ICN node can simultaneously receive Interest packets with the same name from multiple ports of the ICN node, so the receiving port list corresponding to the same name in the PIT table may include multiple receiving ports.

S303. If yes, update the receiving port list corresponding to the name of the Interest packet in the PIT table with the receiving port of the Interest packet. In this case, it indicates that the Interest packet corresponding to the name has been forwarded by the ICN node, but the data packet corresponding to the Interest packet has not been received, so the Interest packet is not forwarded at this time. Instead, it waits to receive the data packet corresponding to the Interest packet or waits for the PIT record to expire, so as to prevent the same request from being repeated in a short period of time and waste network resources.

It should be noted that the PIT table is not repeatedly added.

Here, updating the receiving port list corresponding to the name in the PIT table, for example, adding the receiving port that received the Interest packet to the receiving port list corresponding to the Interest packet name in the PIT table.

S304. If not, judge whether there is the name of the interest packet in the preset history record table; the preset history record table includes a plurality of history records, wherein each history record includes: the first ICN The name of the data packet received by the node, the receiving port of the data packet, the receiving time of the data packet and the survival time of the record; if there is, then execute step S305, otherwise, execute step S306;

S305. If yes, forward the Interest packet from the destination port to a third ICN node, and update the preset PIT table with the name of the Interest packet and the receiving port that received the Interest packet; The port is the receiving port stored in the preset history table and corresponding to the name of the Interest packet. Updating the preset PIT table with the name of the Interest packet and the receiving port that received the Interest packet, for example, adding the name and receiving port of the received Interest packet as a PIT record to the PIT table.

If there is the name of the received interest packet in the history record table, it indicates that the next-hop ICN node of the ICN node that received the interest packet has probably cached the data packet requested by the interest packet, so The Interest packet is directly forwarded to the ICN node that may have cached the data packet corresponding to the Interest packet, so that the cache utilization rate is improved and the service time of the user request can be reduced.

As can be seen from the above, the present invention predicts the content of the neighbor node cache according to the historical records to guide the subsequent forwarding request (ie, the interest packet), so that the cache utilization rate is improved, and the link load is balanced at the same time, reducing network congestion and reducing network congestion. The service time of user requests is shortened and the user experience is improved.

S306. If there is no name of the interest packet in the preset history record table in the step S304, then judge whether there is a name prefix matching the name of the interest packet in the preset FIB table; Including a plurality of FIB records, wherein each FIB record includes: a name prefix, a port corresponding to the name prefix, and weight value information of the port; if so, perform step S307, otherwise, perform step S308;

S307. If yes, forward the Interest packet to the third ICN node according to the weight value information of each port in the FIB record to which the name prefix belongs, and combine the name of the Interest packet with the received Interest packet The receiving port of is stored in the PIT table;

S308. Forward the Interest packet from ports other than the port receiving the Interest packet, or discard the Interest packet.

The present invention takes into account the important factor of network cache while taking into account load balancing. The present invention uses its own historical records to predict the information cached by neighbors, thereby guiding the forwarding of subsequent interest packets, achieving a synergistic effect, improving the cache utilization rate of the network, and for content that is not in the historical records, The forwarding request (that is, interest packet) is guided by the weight value of each port of the ICN node, so as to ensure the balance of link load and reduce network congestion, that is, the Fib-weight strategy.

The weight value information in the FIB table is the same as the calculation method of the Fib-weight strategy in the background art, and will not be described in detail.

Before the step S301, the method also includes:

S309. Create a history table, the history table includes a plurality of history records, wherein each history record includes: the name of the data packet received by the ICN node, the receiving port of the data packet, the reception of the data packet time and the lifetime of the record.

Initially, the history record table is empty, when the ICN node receives a data packet, according to the following rules, a record is stored in the history record table.

After the interest packet is forwarded from the destination port to the third ICN node in the step S305, the method further includes:

S401. Receive a data packet; the data packet includes the name of the data packet;

S402. Determine whether the name of the data packet exists in the preset PIT table according to the name of the data packet; if yes, execute step S403; otherwise, execute step S404;

S403. If there is, forward the data packet from the destination return port, and delete the PIT record corresponding to the name of the data packet in the preset PIT table; at this time, the Interest packet recorded in the PIT table is explained The content of the request has been satisfied, so delete the corresponding PIT record.

S404. If not, discard the data packet. At this time, it may be maliciously forwarded, but the content of the data packet has not been requested, so it is directly discarded and no longer forwarded.

After the step S403, execute step S405; S405, judge whether to cache the data packet according to the preset caching rules, and judge whether to save the name of the data packet, receiving port, receiving time and the The survival time of each record is stored as a historical record in the preset historical record table;

The destination return ports are all receiving ports corresponding to the names recorded in the preset PIT table.

The present invention forwards the request of the interest packet to the exit in the history record as much as possible, so that the cache of the history can be utilized to the greatest extent. However, it is found in the simulation that if the default cache mechanism of ICN is used: every place saves (LeaveCopyEverywhere, LCE) Placement algorithm + least recently used (LeastRecentlyUsed, LRU) replacement algorithm, the cached content is often replaced. This is related to the setting of the cache capacity and the location of the node. In order to prevent popular content from being frequently replaced, a promotion strategy called limited LRU is proposed based on local popularity statistics.

Specifically, the limited LRU is embodied in the present invention as:

In the step S405, judging whether to cache the data packet according to the preset cache rules includes:

S501. Judging whether the size of the data packet is smaller than or equal to the remaining buffer space of the first ICN node; if so, perform step S502, otherwise, perform step S503;

S502. If yes, cache the data packet;

S503, if not, then judge whether the popularity of the name of the data package is greater than or equal to a preset popularity threshold; if greater than or equal to, then perform step S504, otherwise, perform step S505;

S504. If it is greater than or equal to, judge whether the popularity of the name of each data packet cached in the first ICN node is less than the preset popularity threshold; if less, perform step S506, otherwise, perform step S505;

S505. Do not cache the data packet;

S506. If it is smaller, judge whether the sum of the capacity of the replaceable data packet and the remaining buffer space of the first ICN node is greater than or equal to the size of the data packet; the replaceable data packet is cached in the ICN node If the popularity of its name is less than the preset popularity threshold; if it is greater than or equal to, then perform step S507, otherwise, perform step S505;

S507. If greater than or equal to, replace the replaceable data packet with the data packet.

It is worth noting that: the remaining cache space is the difference between the total cache space of the ICN node and the space occupied by the cached data packets.

The present invention stores more content as much as possible when the cache is not full, so as to expand the types of cache; when the cache is full and needs to be replaced after the cache is full, the content with lower popularity is replaced preferentially to ensure that the content with higher popularity Content is stored in the cache for as long as possible to serve subsequent requests, thereby improving cache utilization.

The resources on the network are unlimited. If all resource information is added to the history record table, the history record table will become very large, occupying more storage resources of the system, and increasing the query time. For ICN such Not very practical for systems that require wire-speed forwarding. According to the twenty-eight principle of network traffic, that is, eighty percent of the network traffic is generated by twenty percent of the content, in the step S405, it is judged whether the name of the data packet, The receiving port, receiving time and survival time of the record are stored as a historical record in the preset historical record table, including:

S601. Calculate and sort the popularity of names stored in the preset history table;

S602. Determine whether the popularity sequence of the name of the data package is less than or equal to a preset value; if less than or equal, perform step S603, otherwise, perform step S604;

S603. If it is less than or equal to, store the name of the data packet, the receiving port, the receiving time, and the survival time of the record as a history record in the preset history record table. For example, update the receiving port of the name in the history record to the port that received the data packet.

S604. Discard the data packet and not store the record.

Through this method, the content with relatively low popularity is not recorded in the history record table. For the content with high popularity, it means that the content is hotter and has more requests, and it is recorded in the history record table, so that Serve subsequent requests to improve cache utilization. The statistical calculation of popularity can use known methods.

Each historical record has a survival time, counting from the receiving time, if the survival time is exceeded, the historical record will be considered invalid and cleared.

It is difficult to set the survival time. If the survival time is set too large, the request will be guided blindly. The history records indicate that the next item exists, but the content of the next node cache has been replaced after a long time ; On the contrary, if the lifetime is set too small, it will not play a role in guiding forwarding. Therefore, in order to provide better services to users, this survival time is generally set according to experience values.

The ICN node in the present invention may be a forwarding router, the second ICN node may be a terminal, and the third ICN node may be a forwarding router or a server.

The method adopted by the present invention is named CAMF strategy.

In order to verify the concrete effect of this scheme, the present invention is illustrated by simulation. Please refer to the topology diagram shown in Figure 5, terminal a can reach the server "/a" through three roads R1-R2-R5, R1-R3-R5, and R1-R3-R5. There are 100 data packets in total, all of which are 1KB in size, and the buffer size of each node is 5KB. The random strategy, the fib-weight strategy and the CAMF strategy of the present invention are separately executed on R1. The request rate is 100 per second, the bandwidth between {R1, R2...R5} is the same and the change range is [100kbps, 450kbps], the simulation time is 1000 seconds, and the corresponding simulation results are shown in Figure 7 and Figure 8. Fig. 7 shows the number of data packets successfully requested by terminal a after the simulation, and Fig. 8 shows the average time delay of successful requests. It can be seen that the method of the present invention helps to improve the performance of the network and reduce the time delay of the network. In Fig. 7, the abscissa represents the link bandwidth, and the ordinate represents the number of successful requests. In Fig. 8, the abscissa represents the link bandwidth, and the ordinate represents the average request delay.

The requests in this article refer to the requests of Interest packets in the ICN framework.

Figure 1, Figure 2, and Figure 6 do not distinguish between the name and the prefix of the name, please use the text description for details.

FIG. 9 is a functional block diagram of a multi-path forwarding system of an information center network based on historical records provided by an embodiment of the present invention.

With reference to Fig. 9, a kind of multi-path forwarding system of the information center network based on historical record, described system comprises:

The receiving unit 901, the first ICN node in the ICN architecture receives the Interest packet sent by the second ICN node, and the Interest packet includes the name of the Interest packet;

The first judging unit 902 judges whether there is the name of the Interest packet in the preset PIT table; the PIT table includes a plurality of PIT records, and each PIT record includes: the name of the pending Interest packet, and the name The receiving port list of the corresponding pending Interest packet and the survival time of the PIT record, the pending Interest packet is an Interest packet that has been forwarded by the first ICN node but has not yet received a data packet corresponding to the Interest packet;

The second judging unit 903, if not, judges whether there is the name of the interest packet in the preset history record table; the preset history record table includes a plurality of history records, wherein each history record includes: The name of the data packet received by the first ICN node, the receiving port of the data packet, the receiving time of the data packet and the survival time of the record;

The first forwarding unit 904, if any, forwards the interest packet from the destination port to the third ICN node, and updates the preset PIT table with the name of the interest packet and the receiving port that received the interest packet ; The destination port is the receiving port stored in the preset history table and corresponding to the name of the Interest packet.

Further, the system also includes:

The third judging unit, when there is no name of the interest packet in the preset history record table, then judge whether there is a name prefix matching the name of the interest packet in the preset FIB table; the FIB table includes multiple A FIB record, wherein each FIB record includes: a name prefix, a port corresponding to the name prefix, and weight value information of the port;

The second forwarding unit, if any, forwards the interest packet to the third ICN node according to the weight value information of each port in the FIB record to which the name prefix belongs, and sends the name of the interest packet and the received The receiving port of the Interest packet is stored in the PIT table.

Since there is a one-to-one correspondence between the multi-path forwarding system of the historical record-based information center network and the multi-path forwarding method of the historical record-based information center network in the present invention, the system will not be described in detail here.

Those of ordinary skill in the art can understand that: the above embodiments are only used to illustrate the technical scheme of the present invention, rather than limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand : It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements to some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the claims of the present invention. range.

Claims (10)

1. a kind of multi-path forwarding method of the information center network based on historical record, it is characterized in that, comprise a plurality of nodes in the ICN framework, described method comprises: The first ICN node in the ICN architecture receives the Interest packet sent by the second ICN node, and the Interest packet includes the name of the Interest packet; Judging whether there is the name of the interest packet in the preset PIT table; the PIT table includes a plurality of PIT records, and each PIT record includes: the name of the pending interest packet, the name of the pending interest packet corresponding to the name Receive a port list and the lifetime of the PIT record, the pending Interest packet is an Interest packet that has been forwarded by the first ICN node but has not received a data packet corresponding to the Interest packet; If not, it is judged whether there is the name of the interest packet in the preset history record table; multiple history records are included in the preset history record table, wherein each history record includes: the first ICN node receives The name of the received data packet, the receiving port of the data packet, the receiving time of the data packet and the survival time of the record; If so, forward the interest packet from the destination port to the third ICN node, and update the preset PIT table with the name of the interest packet and the receiving port that received the interest packet; the destination port is The receiving port corresponding to the name of the Interest packet stored in the preset history record table. 2. The method according to claim 1, wherein, after judging whether there is the name of the interest packet in the preset history table, the method also includes: If not, then judge whether there is a name prefix matching the name of the interest packet in the preset FIB table; multiple FIB records are included in the FIB table, wherein each FIB record includes: name prefix, and the The port corresponding to the name prefix, and the weight value information of the port; If so, according to the weight value information of each port in the FIB record to which the name prefix belongs, forward the interest packet to the third ICN node, and send the name of the interest packet and the receipt of the interest packet Ports are stored into the PIT table. 3. The method according to claim 1, characterized in that, after judging whether there is the name of the interest packet in the preset PIT table, the method also includes: If yes, update the receiving port list corresponding to the name of the Interest packet in the PIT table with the receiving port of the Interest packet. 4. The method according to claim 1, wherein, before the first ICN node in the ICN architecture receives the Interest packet sent by the second ICN node, the method further comprises: Create a historical record table, including a plurality of historical records in the historical record table, wherein each historical record includes: the name of the data packet received by the ICN node, the receiving port of the data packet, the receiving time of the data packet and The lifetime of this record. 5. The method according to claim 1, wherein, after the interest packet is forwarded from the destination port to the third ICN node, the method further comprises: Receiving a data packet; the data packet includes the name of the data packet; judging whether the name of the data packet exists in the preset PIT table according to the name of the data packet; If so, the data packet is forwarded from the destination return port, and the PIT record corresponding to the name of the data packet is deleted in the preset PIT table; Judging whether to cache the data packet according to the preset caching rules, and judging whether to store the name of the data packet, the receiving port, the receiving time and the survival time of the record as a historical record in the data packet according to the preset storage rules In the preset history table mentioned above; The destination return ports are all receiving ports corresponding to the names recorded in the preset PIT table. 6. The method according to claim 5, wherein judging whether to cache the data packet according to a preset cache rule comprises: judging whether the size of the data packet is less than or equal to the remaining cache space of the first ICN node; If not, then determine whether the popularity of the name of the data package is greater than or equal to a preset popularity threshold; If it is greater than or equal to, it is judged whether the popularity of the name of each data packet cached in the first ICN node is less than the preset popularity threshold; If less, then judge whether the sum of the capacity of the remaining cache space of the replaceable data packet and the first ICN node is greater than or equal to the size of the data packet; the replaceable data packet is cached in the ICN node, A data packet whose name popularity is less than the preset popularity threshold; If greater than or equal to, replace the replaceable data packet with the data packet. 7. The method according to claim 5, wherein, judging according to a preset storage rule whether to store the name of the data packet, the receiving port, the receiving time and the survival time of the record as a historical record in the The preset history tables mentioned above include: calculating and sorting the popularity of the names of the data packages stored in the preset history table; Judging whether the popularity order of the name of the data package is less than or equal to a preset value; If it is less than or equal to, the name of the data packet, the receiving port, the receiving time and the survival time of the record are stored as a historical record in the preset historical record table. 8. The method according to claim 5, wherein, after judging whether there is the title of the data package in the preset PIT table according to the title of the data package, the method also includes: If not, the data packet is discarded. 9. A multi-path forwarding system of an information center network based on historical records, characterized in that the system comprises: A receiving unit, the first ICN node in the ICN architecture receives the Interest packet sent by the second ICN node, and the Interest packet includes the name of the Interest packet; The first judging unit judges whether there is the name of the interest packet in the preset PIT table; the PIT table includes a plurality of PIT records, and each PIT record includes: the name of the pending interest packet, corresponding to the name The receiving port list of the pending Interest packet and the survival time of the PIT record, the pending Interest packet is an Interest packet that has been forwarded by the first ICN node but has not yet received a data packet corresponding to the Interest packet; The second judging unit, if not, judges whether there is the name of the interest packet in the preset history record table; multiple history records are included in the preset history record table, wherein each history record includes: the The name of the data packet received by the first ICN node, the receiving port of the data packet, the receiving time of the data packet and the survival time of the record; The first forwarding unit, if any, forwards the interest packet from the destination port to the third ICN node, and updates the preset PIT table with the name of the interest packet and the receiving port that receives the interest packet; The destination port is the receiving port stored in the preset history table and corresponding to the name of the Interest packet. 10. The system according to claim 9, further comprising: The third judging unit, when there is no name of the interest packet in the preset history record table, then judge whether there is a name prefix matching the name of the interest packet in the preset FIB table; the FIB table includes multiple A FIB record, wherein each FIB record includes: a name prefix, a port corresponding to the name prefix, and weight value information of the port; The second forwarding unit, if any, forwards the interest packet to the third ICN node according to the weight value information of each port in the FIB record to which the name prefix belongs, and sends the name of the interest packet and the received The receiving port of the Interest packet is stored in the PIT table.