CN111934717A

CN111934717A - Cooperative neighbor discovery and access control protocol based on electric power broadband carrier

Info

Publication number: CN111934717A
Application number: CN202010772218.4A
Authority: CN
Inventors: 孙侃; 卜权; 丁旸; 张红
Original assignee: Jiayuan Technology Co Ltd
Current assignee: Jiayuan Technology Co Ltd
Priority date: 2020-08-04
Filing date: 2020-08-04
Publication date: 2020-11-13

Abstract

The invention discloses a cooperative neighbor discovery and access control protocol based on electric power broadband carrier waves, which comprises the following steps: setting the waking time of a station in a high-speed carrier communication network as a multiple of a prime number, automatically selecting the prime number by a global calculator of a neighbor discovery protocol, and matching an expected station working period or discovery delay when each multiple of the prime number is selected; the station selects a working period or discovery delay, and obtains the minimum discovery delay of the working period; the station acquires communication neighbor information, and executes an access control protocol after the verification of all communication neighbors is completed; identifying real neighbors based on the positioned route distribution protocol, and selecting relay stations to forward data through a multipoint relay route; the invention can improve the data packet forwarding efficiency by realizing the neighbor discovery protocol in the broadband power line carrier communication network, the protocol has good discovery performance, minimum discovery delay and maximum working period, the safety is higher, and the site discovery delay can be effectively controlled.

Description

Cooperative neighbor discovery and access control protocol based on electric power broadband carrier

Technical Field

The invention relates to the technical field of broadband carriers, in particular to a cooperative neighbor discovery and access control protocol based on electric broadband carriers.

Background

With the popularization and rapid development of the internet, IPv4 has revealed many disadvantages, such as lack of address resources, low quality of service, lack of mobility, weak auto-configuration capability, and poor security, and the transition of IPv4 to the next generation internet protocol (IPv6) is a necessary trend in the development of the internet. The neighbor discovery protocol is a basic protocol in an Ipv6 protocol cluster and provides functions of router discovery, stateless address automatic configuration, repeated address detection, link layer address resolution, neighbor unreachable detection and the like for network stations. The neighbor discovery protocol operates at the network layer and is responsible for discovering other sites and corresponding addresses on the links, determining available routes and maintaining information reachability about available paths and other active sites.

The power line communication environment is severe, the characteristics of high attenuation, strong noise, high impedance and the like are achieved, and a network layer needs to solve the problem through a relay routing technology in order to realize high-reliability data transmission.

Disclosure of Invention

The invention aims to provide a cooperative neighbor discovery and access control protocol based on an electric broadband carrier, so as to solve the problems of the prior art that the neighbor discovery protocol of Ipv6 has a security defect and the discovery delay is too long.

In order to achieve the purpose, the invention is realized by adopting the following technical scheme:

the cooperative neighbor discovery and access control protocol based on the electric power broadband carrier comprises the following steps:

setting the waking time of a station in a high-speed carrier communication network as a multiple of a prime number, automatically selecting the prime number by a global calculator of a neighbor discovery protocol, and matching an expected station working period or discovery delay when each multiple of the prime number is selected;

the station selects a working period or discovery delay, and obtains the minimum discovery delay of the working period;

the station acquires communication neighbor information, and executes an access control protocol after the verification of all communication neighbors is completed;

and identifying real neighbors based on the positioned route distribution protocol, and selecting relay stations to forward data through the multipoint relay route.

Further, the selecting the neighbor by the multipoint relay route specifically includes:

each station in the high-speed carrier communication network acquires communication neighbor station information;

and selecting the optimal relay station according to the communication neighbor station information.

Further, the access control protocol specifically includes the following steps:

a user defines a resource address and a request address of a requester and executes an access control strategy;

the bit currency converts the access strategy into a script language to obtain a transaction, and a user private key signs the transaction and then spreads the transaction to a network to obtain an access token and a requester address;

each site verifies the transaction in the transaction verification process, and if the transaction is valid, the access token and the requester address are recorded into the blockchain;

the requester scans the block chain, acquires access tokens and requester addresses related to all client addresses, scans an access token and requester address database, and acquires the maximum throughput;

the throughput under the access transaction is kept maximum, the transaction is broadcasted to the network, whether the transaction is effective or not is verified, and if the transaction is effective, a requester is informed;

when the client meets the access condition, transmitting the access token and the requester address to the client;

the user executes the maximum throughput ultra-low power access control strategy; the bitcoin sends the maximum throughput ultra-low power access transaction;

the blockchain and bitcoin network verify the transaction, and the requester scans with the token in the transaction;

if the requester meets the access control condition, acquiring an access token and a requester address through the maximum throughput ultra-low power access transaction;

according to the technical scheme, the embodiment of the invention at least has the following effects:

1. the energy-efficient safe distributed cooperative neighbor discovery protocol based on the broadband power line carrier communication network is provided, and the performance and the effectiveness of the broadband power line carrier communication network are improved. A maximum throughput access control protocol with ultra-low power limitations based on a blockchain internet of things framework is proposed. The invention adopts the relay station to forward the data. The neighbor discovery protocol is implemented in the broadband power line carrier communication network, so that the data packet forwarding efficiency can be improved. The protocol has good discovery performance, minimum discovery delay and maximum work period, is relatively high in safety, and can effectively control site discovery delay.

2. The invention provides an energy-efficient safe distributed cooperative neighbor discovery protocol working in an asynchronous mode, and allows a plurality of stations to work in a small working period, and mutually discover and opportunistically communicate with each other. Found to be fast, reliable, predictable over a range of operation. The key challenge is to achieve an optimal balance between low power, maximizing life cycle, and detecting the active flexibility of new site occurrences.

3. The invention adopts the relay station to forward the data. The neighbor discovery protocol is implemented in the broadband power line carrier communication network, so that the data packet forwarding efficiency can be improved. According to the routing scheme idea adopted by the invention, each station continuously exchanges the information of the surrounding neighbor stations, so that each station can master the communication state of the whole network, and further, the optimal relay is selected from the neighbor stations. And upgrading the station selected as the relay into a cluster head, wherein the sub-station is a cluster member station, and the cluster head station is responsible for data forwarding of all sub-stations under the cluster head station. The routing scheme is a distributed relay routing scheme, and each station automatically searches for an optimal communication path.

Drawings

FIG. 1 is a discovery protocol timing diagram in accordance with an embodiment of the present invention;

FIG. 2 is a timing diagram of a newly discovered protocol in accordance with an embodiment of the present invention;

FIG. 3 is a diagram of an optimal duty cycle according to an embodiment of the present invention;

FIG. 4 is a graph illustrating the variation of slot length with increasing discovery delay for different duty cycles in accordance with an embodiment of the present invention;

fig. 5 is a graph illustrating a change of a minimum duty cycle as a maximum discovery delay becomes longer in a cluster mode K of 4+6z with different slot lengths according to an embodiment of the present invention;

FIG. 6 is a graph of discovery rate versus time in accordance with an embodiment of the present invention;

FIG. 7 is a graph of discovery rate versus time in accordance with an embodiment of the present invention;

fig. 8 is a graph of discovery delay for 6 neighbors when a station enters a cluster of 7 stations, embodying the present invention.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

The cooperative neighbor discovery protocol includes the following parts:

1. cooperative neighbor discovery model

The communication neighbors of a station U can be defined as the set of stations c (U) that send information directly to U. A station V is a communication neighbor of station U only if station U can receive the signal sent by station V. If V is in the normal communication range r, U can directly receive the information of V. The physical neighborhood of a station U can be defined as the set of stations p (U) that are within a physical distance r from U.

Station V increases transmission power, upgrades its transceiver beyond the desired communication range, and belongs to c (u) instead of p (u). V ∈ P (U) cannot directly send information to U because of a barrier,

under an ideal communication model, U and V communicate neighbor distances r, and the two types of neighbors are the same. Even when V ∈ C (U), U does not belong to C (V), and it is not necessary to send information directly to V.

2. Protocol procedure

Physical access control: scanning an RFID tag with a tag reader received a signal may be used to authenticate the tag carrier into the building. The received signal implies that the tag is mostly within a predetermined distance of the particular system from the tag reader. Physical access control systems leverage limited range communication performance.

Network access control: only registered users or devices are allowed to access network resources. A station can only acquire network connectivity if it is within range of a WLAN Access Point (AP) or a cellular system base station. Access control relies on communication neighbor discovery. Eavesdropping can be prevented by encryption when only message modifications and deletions are detected.

Routing: in multi-hop wireless networks, all types of data communication and data distribution single-point, multi-point or broadcast transmission rely on an understanding of the neighbors. Neighbors of each station are stations that can receive and forward control traffic and data from the station, e.g., route discovery and communication with another destination station. If a destination station is identified as a neighbor, no route discovery or computation is required. A location-based routing protocol is employed to select neighbors that are close to the destination site location. Communication neighbor discovery is necessary. A complete, efficient, fault-tolerant neighbor discovery protocol would be desirable. Assuming that many or even all neighbors have been discovered, a suitable neighbor is selected to forward the data or an alternative path is used.

3. Energy efficient secure distributed cooperative neighbor discovery protocol

The effective path prediction algorithm can help to design a neighbor discovery protocol which is rapid, safe, reliable, flexible and predictable. This protocol can ensure that stations do not overlap when they set their own duty cycles independently.

Once a neighbor is discovered, the awake mechanism is started, with synchronous rendezvous during idle periods and asynchronous rendezvous during busy periods.

The invention provides a low-power maximum throughput energy-limited hybrid synchronous and asynchronous rendezvous automatic neighbor discovery protocol. Cooperative location discovery at low duty cycles is to maximize the life cycle. Setting the awake time of a station to a multiple of a prime number may ensure deterministic pairwise discovery and periodic local negotiation duty cycle. The algorithm selects a pair of prime numbers such that the sum of their inverses equals the desired station duty cycle.

If the local counter is divisible by any prime number, the station opens a counter cycle for the station. The new protocol designs that the global counter is divisible by the prime number that can be selected. This is a low complexity, adaptive, distributed neighbor discovery protocol. Each high speed carrier communication unit site first selects a discovery delay or a desired duty cycle. The global negotiation duty cycle minimizes discovery delay. The global counter in the new protocol may automatically select a prime number that matches the expected duty cycle or discovery delay at each multiple of the prime number selected. During each idle period, a station may listen, beacon, or both. Sites may be assigned to different clusters so that the inter-cluster discovery time is much faster than if there were no classification, and the sites may adjust the duty cycle to minimize some discovery delay. The new protocol provided by the invention adopts a cluster mode, and a group of stations form a unit. The station periodically sends beacons to the neighbors that appear, flexibly selecting the best station to be the neighbor instead of the first station. The station only sends beacons and listens for neighbors after an adjustable period. The station keeps discovering one or more neighbors time synchronized by sending a long preamble. By varying energy availability, idle listening occupies the system power budget, and the duty cycle of the listening is reduced for power delivery.

The asymmetric duty cycle is used for low power listening and sensing and has to be adjusted to the available energy and adaptive listening period. Periodically monitoring the whole synchronization period to find the neighbor. The proposed protocol divides time into a series of beacon slots. The station transmits and receives within each cluster slot using the input row and column.

3.1 protocol model for reduced mode

Asynchronous and synchronous rendezvous allow stations to send messages to previously discovered neighbors within a predictable and controllable delay. Two sites m and n, denoted A using 2 prime numbers_mAnd A_n，1/A_mAnd 1/A_nEqual to the desired duty cycles of m and n, respectively. Time is dividedDivided into successive periods. Station at time a_mAnd a_nTime of day use counter C_mAnd C_nA counting period is started and m and n are synchronously counted to a reference period. If C_m|A_m＝1(C_mExcept for A_m) M turns on the station to transmit a beacon within one period. When C is present_n|A_nM and n turn on stations in the same period, which can exchange beacons and discover each other.

Assume an overlap period of A-A_mA_nThe period, K, denotes the reference period number,

C_m＝K-a_m

C_n＝K-a_n

the main goal is to find K so that C can be known_m|A_mAnd C_n|A_n。

K≡a_m(modA_m)

K≡a_n(modA_n).

If k is₀Is a solution, when z is some integer, K ═ K₀+zA。

When k is₀＝a_mb_mA_m+a_nb_nA_n,

b_mA_n≡1(modA_m)

b_nA_m≡1(modA_n)。

If site m selects A_m3, then the duty cycle of m is DC 33%, the counting starts at reference point K1, then a_m1, with a counter value C_m0. If site n selects A_nThen n has a duty cycle of DC-20%, starting at reference point K-2, then a_m2, with a counter value C_m3. When m and n have an overlap on the slots, they can communicate. When K-7 and K-22, both m and n are open and found each other. For all Z ∈ Z⁺，K＝7+15z_。The discovery process in the simplified mode is described in fig. 1. Two stations m and n, starting counting C at the time K1 and K2_mAnd C_nPeriod A_m3 and A_nDuty cycle 33% and 20%. The grey squares represent the times at which stations m and n open a station. Stations m and n find each other at times K7 and K22.

K≡1(mod3)

K≡2(mod5)

When the K is equal to 7,

(7-1)|3

(7-2)|5

an analytical solution needs to be found b_mAnd b_n

5b_m≡1(mod3)

3b_n≡1(mod5)

When b is_m2 and b_n2, one solution k₀Is that

k₀＝a_mb_mA_n+a_nb_nA_m

k₀＝1*2*5+2*2*3

k₀＝22

All solutions are unique (mod15),

k₀＝22(mod15)＝7

so when Z ∈ Z⁺，K＝7+15z。

3.2 Cluster mode

In the simplified discovery mode, sites m and n discover each other twice. Synchronizing their counts in the reference phase, the present invention proposes a new cluster discovery mode, using A_n2, DC 50%. So stations m and n are found at time K4, K10, K16 and K22. Considering minimizing energy load, maximizing throughput, ultra-low power limit, for all Z ∈ Z⁺And K is 4+6 z. The cluster mode of the newly discovered protocol is depicted in fig. 2. Two stations m and n, starting counting C at the time K1 and K2_mAnd C_nPeriod A_m3 and A_nDuty cycle 33% and 50%, 2. The grey squares represent the times at which stations m and n open a station. Stations m and n find each other at times K4, K10, K16 and K22.

3.3 selecting the optimal duty cycle

When A is_m＝A_nIf stations m and n are awake at different stages of the same cycle, they will not find each other. It is desirable to meet their respective duty cycle requirements. Site m uses two different prime numbers D_m1And D_m2Selecting the optimum duty cycle with the sum of their inverses being equal to the desired duty cycle

For each station pair m and n, the different stations independently select the duty cycle. The stations being relatively prime to each other

gcd(D_m1,D_m2)＝gcd(30,77)＝1

gcd(D_n1,D_n2)＝gcd(35,66)＝1

However, the stations are not coprime to the outside and cannot find each other. When all Z ∈ Z⁺Station m starts counting at time K30 z and K77 z, and station n starts counting at time K35 z +1 and K66 z + 1.

gcd(D_m1,D_n1)＝gcd(30,35)＝5

gcd(D_m1,D_n2)＝gcd(30,66)＝6

gcd(D_m2,D_n1)＝gcd(77,35)＝7

gcd(D_m2,D_n2)＝gcd(77,66)＝11

3.4 selecting the best prime number

The choice of prime number may determine the discovery delay, which is good and small. If two stations select the same duty cycle, the randomized selection of prime pairs reduces the chance that two stations select the same pair.

If a site can be assigned to different clusters, the members of one cluster need to select the best prime number pair. For each duty cycle, each station generates an ordered list of prime number pairs to meet the duty cycle requirements.

The station randomly selects one of the prime number pairs to assign to its cluster. The new cluster discovery protocol ensures that stations of different clusters are allocated different prime number pairs, so that the discovery delay performance can be greatly improved. A good choice of external clusters is important for cluster allocation. Beacons are transmitted at the beginning and end of a slot, maximizing the likelihood of overlapping slots leading to discovery.

When the channel is busy, the beacon is transmitted blindly. The time to effectively switch off the time slot may mitigate long delays.

3.5 discovery delay

The duty cycle or beacon rate is calculated to meet the discovery delay requirement. The goal is to calculate the minimum duty cycle and discovery delay. The main task is to delay the maximum discovery by T_maxAnd converted into a duty cycle. Different sites are assigned to different clusters, limiting discovery delay. Prime number D for two sites_m1And D_m2Is shown to be at D_m1D_n2The counter periods are found each other, each counter period length T_slot。

D_m1D_n2T_slot≤T_max (1)

Minimum duty cycle is satisfied

The minimum beacon rate can be obtained by

Although the beacon rate follows T_slotThe effective work period is reduced

Duty cycle granularity is represented in the best Duty Cycle (DC) figure 3.

3.6 Security mechanism

The neighbor discovery protocol identifies real neighbors through a positioning-based routing distributed protocol, and selects proper neighbors to forward data through a multipoint relay routing mechanism.

A station may obtain neighbor information in an unsecured manner but perform authentication to obtain secure neighbor discovery. Some neighbor discovery protocols are unable to discover and verify all neighbors. This problem can be solved by autonomous device negotiation, ensuring that high speed carrier communication networks achieve message delivery through point-to-point messaging and distributed file sharing.

In the point-to-point messaging approach, encrypted message transmission is kept low latency, ensuring that store and forward messages are transmitted with other connected stations. Such messaging capabilities are obtained using structured point-to-point networks. A Distributed Hash Table (DHT) may be used to enable a station to find other stations in the network. Each site will generate its own unique public key based on the address (hash table name) and send and receive encrypted packets with other sites, and any participating site can effectively retrieve the associated value of a given key.

Distributed file sharing enables distributed software updates, reporting security files and data sharing based on the analyzed site. Distributed peer-to-peer networks use DHTs to effect the migration. An attacker blocking communication prevents discovery of one, many, or even all stations that may be neighbors. In the peer-to-peer file sharing protocol, multiple sites employ different NAT systems to maintain efficient communication.

Two stations tunnel and send control traffic to each other in their respective neighbor discovery protocols, so they appear as neighbors in route discovery in the routing protocol. The identity of the station is established in a secure neighbor discovery protocol, and a Distance Binding (DB) method estimates the distance to a potential neighbor V by measuring the signal round-trip delay and multiplying by the signal propagation speed. The DB protocol can ensure physical neighbor discovery, if distance r is obtained, the true distance to V is less than or equal to r.

The neighbor acts as a cluster, and station X sends a beacon that X can digitally sign with its private key, and when Y receives the beacon and adds X to set c (Y), the signature is valid. The measurement delay uses fast bit exchange, and the neighbor stations complete simple and low-complexity calculation. At maximum station speed, the station can check whether the received message originates from a sender at a given distance.

The access control protocol comprises the following parts:

the invention provides a novel maximum throughput access control framework based on ultra-low power limitation of an Internet of things block chain technology. The fair access control model uses bitcoin addresses to identify all interacting entities in the authentication mechanism. An entity refers to a communication unit or other physical device. It uses blockchains to ensure evaluation and access policy enforcement as well as token authenticity. In the fair access process, the blockchain is regarded as a database, all access control policies are stored in a transaction form in each pair (resource, requester), and the audit function is ensured by logging in the database. An authentication token is defined as a digital signature that indicates that the creator, having access rights or authorized a transaction, may access a particular resource based on its address. The authentication token is treated as a new area of stored data inside the blockchain, encrypted using an embedded public/private key mechanism.

The block chain technology based on token access control has many advantages in the field of power carrier communication of the Internet of things. The high-speed carrier communication module can verify the validity of the access token, relieve the condition that the Internet of things equipment needs to process a large amount of access control information, and ensure the end-to-end safety of a credible strong entity.

4.1 user

Either the requestor or the RO owns the resource of the resource access provider. Requestors and their resources are identified by addresses, interacting with each other through transactions.

4.2 addresses

The user RO or the requesting party and their resources may have a virtually unlimited amount of encrypted identification, called an address. The addresses are common, shared, in the network. The address is a hash of the Elliptic Curve Digital Signature Algorithm (ECDSA) public key, with a user having a corresponding private key. Addresses are used to identify all entities: RO, requestor, and all types of their resources. The address may enable distributed trust and control, proof of ownership, cryptographic authentication security models.

4.3 transactions

The bit transfer between addresses is called a transaction. The basic building block of the bit transaction is a transaction output UTXO. UTXO is a bit-of-currency value that is locked to a particular user, recorded in a blockchain, and considered as a currency unit throughout the network. The entire network considers an access token TKN as an access right, and the creator of the transaction gives the recipient of the transaction access to the resource via the address in the transaction. One type of transaction is token-based, called max throughput ultra low power access, where the RO defines an access policy and creates a new TKN. A normal transaction refers to any access transaction where the requestor can obtain a TKN from a maximum throughput access transaction and access the resource with an address by satisfying the access control condition or satisfying the delegated access condition. Delegated access refers to a requestor delegating access under new conditions by transferring TKNs to other new users. Each access token TKN is extracted from the address of the requesting party, encrypted with a public key, and assigned to a TKN. The supplicant may decrypt with the private key and access the TKN.

4.4 transaction verification protocol

The framework proposed by the present invention is based on core access control protocols implemented on a blockchain. When a station in the network receives a transaction, a transaction verification protocol is executed. Each site verifies each transaction before forwarding it.

4.5 registering New resources

Sk is a number used to create signatures for transaction verification, proof of ownership of resources and address access controls, extract addresses from their corresponding public keys for maximum throughput access transactions, the public keys being used to identify specific recipients.

One parent key may derive a series of child keys, and each child may derive a series of grandchild keys. And extracting the address of the resource from the RO public key corresponding to the child. The RO can identify the resource by extracting an address through the generated key. The RO is able to derive the public child key from the public parent key without the need for a private key. The RO manages the maximum throughput ultra-low power limit access control policy, registering all resources by deriving the corresponding private key to sign the transaction.

Those resources may use the public key derivation function to create a new address for each transaction. To get an address in order to receive an access request, those interacting entities can obtain a public key instead of a private key. The RO may control access to all resources associated with generating an address using a private key seed key.

The specific flow of the maximum throughput access control protocol with the ultra-low power limitation Internet of things block chain mechanism is as follows:

step 1: RO knows the address of the requester, RO defines the resource address rs, the request address rq, the access control POLICY_rs,rq。

Step 2: the bitcoin converts the access control policy into a scripting language, generates an ultra-low power limited maximum throughput access transaction, signs with the RO private key, and then disseminates into the network

POLICY_rs,rq→π_x (6)

Trading

Tx＝(m,sig_rs(m)) (7)

Where m ═ IDx (IDx, Vin [ input1(tokenbase, rs)],Vout[output1(rq,π_x,TKN_rq,rs)])。

Vin[]Each input in the input vector. Vout [ deg. ]]Each output in the output vector includes a TKN (access token and requestor address) and a locking script. IDx is the index of the current transaction identifier Tx when x ═ h (Tx). The encrypted access token, has a transaction value that extracts the public key from the rq address, which is recorded in the blockchain. rs is the request resource address. rq the address of the requester as the current transaction Tx receiver. Pi_xLocking script, scripting languageAccess control policy of (1).

And step 3: each site verifies the transaction in a transaction verification process.

And 4, step 4: if the transaction is validly output, the TKN is recorded_rq,rsInto a blockchain.

And 5: the requester scans the TKN database by scanning the blockchain, collecting all TKNs associated with the client address. If the TKN database contains TKNs associated with resources, which yield maximum throughput under ultra low power access transactions, then sends a request to the owner containing the address,

ScanTKN(rq)→TKN_rq,rs (8)

decrypt(TKN_rq,rs) (9)

GetLockingscript(TKN)→π′_x (10)

wherein, is'_xIs a locking script in an ultra low power max throughput access transaction.

Step 6: requester is pi'_xGenerating an unlocking script MeetaaccesscontrolPolicy (pi ') under the condition that the maximum throughput low-power access control condition is met'_x)→ψ (11)

And 7: maximum throughput under low power access transactions

Tx＝(IDx,Vin[input1(ref,rs,ψ)],Vout[output1(rq,TKN_rq,rs)])

Where ref is the previous output TKN_B.pk,rsPoint (2) of (c). Psi can obtain TKN_B.pk,rsThe unlock script of (1).

Pk is the address of one of the resources. Pi_xLocking scripts for the new access-control policy. TKN_c.pk,rsThe access token is encrypted.

This blockchain transaction passes the encrypted access token TKN_rq,rsTo the requestor.

And 8: the bitcoin broadcasts the transaction into the network.

And step 9: the network verifies the verification transaction in the authentication protocol, and if the verification is valid, the transaction is included in the blockchain and a notification is sent to the requester.

Step 10: once the transaction occurs in the blockchain, it means that the network witness client satisfies the access condition (unlock script) and then passes the TKN to the client.

Step 16: the RO implements a maximum throughput ultra-low power access control policy.

And step 17: the token is encapsulated in the transaction. The bitcoin transmits a maximum throughput ultra-low power access transaction.

Step 18: blockchains and bitcoin networks authenticate transactions.

Step 19: the supplicant scans with the arriving access token.

Step 20: the requester satisfies the access control condition and obtains TKN through maximum throughput ultra low power access transaction.

Step 21: the requestor obtains the TKN.

In this embodiment, the Central Coordinator (CCO) may set a routing period of the network for 20 to 420 seconds according to the size of the network, and the Station (STA) evaluates its own proxy station in the routing period and may initiate a proxy change request. In the whole network dynamic route maintenance mechanism, the monitoring period of the neighbor network is less than 10 seconds, and after the CCO is powered on, the inter-network coordination frame of the neighbor network is monitored in the period to carry out negotiation of the network identification. The discovery list is a management message which is periodically broadcast and sent by all nodes in the communication network and carries neighbor site list information. The sending period of the discovery list messages is 1 routing period, and all stations in the network send at least 10 discovery list messages in the routing period.

The network identifier is a unique identification number used to identify a high speed carrier communication network. Under the scene of coexistence of multiple networks, the network identifiers of the multiple networks conflict, and central coordinators of the networks ensure that the network identifiers do not conflict through negotiation. The central coordinator of each network coordinates the network identifier and the bandwidth, and ensures that a plurality of networks work normally at the same time.

The basic working frequency band of the terminal power line broadband carrier is 2MHz-12MHz, and can support segmented use. The transmission power spectral density is not more than-45 dBm/Hz in the working frequency band and not more than-75 dBm/Hz outside the working frequency band. Under the condition of isolating a power supply and shielding a standard test environment, the communication speed is not less than 1 Mb/s. The anti-attenuation performance is not less than 85dB under the conditions of power supply isolation, environment shielding, packet loss rate less than 10% (service packet length less than 100B) and in-band emission power spectral density of-45 dBm/Hz in a standard test environment.

The broadband carrier communication unit is provided with a unique node address identifier in a local network and is used for establishing a relay routing relationship. Under the condition of no manual intervention, the relay routing relation of subordinate nodes is automatically managed, and the number of the subordinate nodes is large. And a white list management mechanism of a local communication unit is supported, white list addresses are allowed to be accessed to the network, and nodes which are not in the white list address range are eliminated. The broadband carrier communication unit should support the meter reading in an active mode of a platform area terminal, an active mode of a route and a concurrent mode.

The single-network networking is mainly completed by the CCO sending a central beacon and arranging discovery beacon sending, and sending an agent beacon to trigger a network access request of the STA in a hierarchy level by level. The CCO needs to allocate the TEI to the STA site which is accessed to the network, the TEI of the CCO is fixed to 1, the TEI of the broadcast message is 0xFFF, the TEI allocated range of the CCO is 0-1015, and other addresses are reserved for subsequent expansion use.

After the CCO in the broadband power line carrier communication network is electrified, the network networking process is started. And the CCO sends a central beacon in the beacon time slot to trigger the first-level station to access the network. After receiving the central beacon frame, the non-network-accessing station needs to wait until the CSMA time slot party can initiate an association request. After receiving the association request, the CCO needs to authenticate through a white list, and informs the processing result of the association request to the non-network-accessing site through an association confirmation message or a management summary indication message. If the correlation confirmation message is analyzed to be successful, the TEI distributed by the CCO is obtained, and the website successfully accesses the network; if the result of analyzing the association confirmation message is 'network access failure', network access can be requested again after waiting for a period of time according to the re-association time, and another network can be selected to apply for access. After the current beacon period is finished, the CCO arranges a beacon time slot for the newly accessed station and triggers the surrounding stations to access the network. And after all the sites in the CCO white list successfully access the network, the networking can be considered to be completed.

When a multi-stage station accesses the network, because a station to be accessed is not configured with a TEI at this time, after processing the association request of the STA, the CCO firstly carries the processing result in the generated association confirmation message, sends the association confirmation message to the proxy station of the STA in a hop-by-hop forwarding mode, and then informs the STA station of the access request in a broadcasting mode by the proxy station. The single network networking mechanism is implemented based on queues. After the station successfully accesses the network, the station is added into the accessed network queue; when the station role changes to PCO, it will be added to the PCO queue. The CCO needs to specify beacon transmission slots for all PCOs and an appropriate number of STAs in the central beacon frame every time the CCO schedules beacon frame transmission. Limited by the size of the physical block, if the CCO cannot assign beacon slots to all stations in one beacon frame, the STA needs to be polled, and part of the STAs are scheduled to transmit discovery beacons each time.

The invention adopts the relay node to forward the data. Each node continuously exchanges the information of the neighboring nodes, so that each node can master the communication state of the whole network, and further, the optimal relay is selected from the neighboring nodes. The node selected as the relay is upgraded to a cluster head, the child nodes of the node are cluster member nodes, and the cluster head node is responsible for data forwarding of all the child nodes under the cluster head node. The routing scheme is a distributed relay routing scheme, and each node automatically searches for an optimal communication path.

The throughput and latency performance of the energy efficient secure distributed cooperative neighbor discovery protocol is evaluated below. According to the technical specification of communication interconnection and intercommunication of high-speed carriers of low-voltage power lines, the basic working frequency band of a terminal power line broadband carrier is 2MHz-12MHz, the number of sub-carriers of frame control and load data of each OFDM symbol is 512, the interval of sub-frames is 1 millisecond, and the length of the frame is 10 milliseconds. The sub-carrier interval is 15 KHz-480 KHz, the station delay is 1 millisecond, and the data packet length is 1 millisecond.

Each station has a constant power input and the transaction rate is adjusted based on the dynamic energy storage. Assuming that the stations have the same power consumption and budget, a homogeneous network is formed. For example, P_m＝P，L_m＝L，X_m＝X，

The larger the value of M, the smaller the resulting delay. Because more stations exist in the network, each station is more easily to receive. The power budget is typically 1-10 milliwatts. Each station need not know the number M of stations in the network, as well as other station power consumption and budgets. The neighbor discovery protocol does not consider the station listening transmission power, and does not consider different power consumption.

Fig. 4 is a graph of the change in slot length with increasing discovery delay at different duty cycles. As the duty cycle becomes longer, the slot length becomes correspondingly longer. The reduced mode is shorter than the trunking mode. The duty cycle in trunked mode is longer than in reduced mode.

Fig. 5 is a graph of the minimum duty cycle variation as the maximum discovery delay becomes longer in the cluster mode K-4 +6z with different slot lengths. The shorter the length of time, the longer the minimum duty cycle and the longer the maximum delay.

The station may estimate the number of neighbor discovery stations. The retardation performance was evaluated. In order to accurately measure the power consumption of a station, the station has a large pre-charge capacitor (C)_cap5F) stores energy in advance. The station transmission needs to consume energy, and the monitoring is not energy-consuming. A station may send a data packet of a minimum length of 0.4 milliseconds. Each packet is 40 milliseconds long with an interval of 8 milliseconds. The 6 th or 11 th site acts as a listening site. Each packet contains a station ID and information on the number of packets received from other stations. The throughput is calculated using the divided successful transmission duration. The throughput is evaluated based on the number of different stations M and the power budget P. After each data packet is transmitted, a monitoring interval of 8 milliseconds exists, and the number of arriving bits is effectively reduced.

An important input to the proposed distributed protocol is the estimation of the number of active listeners on the basis of the requestor's decision on which active listener to send continuously

The larger the value, the larger the average pulse lengthLong, throughput can be greatly improved.

Fig. 6 is a graph of discovery rate versus time. The average discovery rate varies linearly with the slot length. At a 10 millisecond slot, 200 neighbors are observed within an average 24 second discovery period. At 25 ms or longer slot values, a maximum of 105 neighbors are observed within an average 60 second discovery period.

Fig. 7 is an analysis diagram of simulation results and actual results in the cluster mode. The only discovered neighbors of a particular listening station are recorded, and the discovery delay of each neighbor is recorded. The actual discovery delay is lower than the simulated discovery delay.

Fig. 8 is a graph of discovery delays for 6 neighbors when a station enters a cluster of 7 stations. Stations have different time slot lengths and different colors. A: t is_slot＝1ms；B：T_slot＝10ms；C：T_slot＝20ms；D：T_slot＝30ms；E：T_slot＝40ms；F：T_slot50 ms. The more neighboring stations, the longer the discovery delay. The longer the slot length, the longer the delay is found, depending on the color.

It will be appreciated by those skilled in the art that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The embodiments disclosed above are therefore to be considered in all respects as illustrative and not restrictive. All changes which come within the scope of or equivalence to the invention are intended to be embraced therein.

Claims

1. The cooperative neighbor discovery and access control protocol based on the electric power broadband carrier is characterized by comprising the following steps of:

2. The cooperative neighbor discovery and access control protocol based on power broadband carrier of claim 1, wherein the routing of neighbors through multipoint relays specifically comprises:

3. The cooperative power broadband carrier-based neighbor discovery and access control protocol of claim 1, wherein the access control protocol comprises: the access control model uses the bitcoin address to identify all interacting entities in the authentication mechanism.

4. A cooperative neighbor discovery and access control protocol based on power broadband carrier according to claim 1 or 3, wherein the access control protocol specifically comprises the following steps:

if the requester meets the access control condition, the access token and the requester address are obtained through the maximum throughput ultra-low power access transaction.

5. A cooperative neighbor discovery and access control protocol based on a power broadband carrier as claimed in claim 1 wherein the routing period of the high speed carrier communication network is 20-420 seconds.

6. A cooperative neighbor discovery and access control protocol based on electric power broadband carrier according to claim 5, wherein the discovery list packet transmission cycle is a routing cycle, wherein the discovery list packet is a management message carrying neighbor site list information and periodically broadcast-transmitted by all sites in the high speed carrier communication network.

7. The cooperative neighbor discovery and access control protocol based on power broadband carrier of claim 1, wherein the station further comprises a network entry before acquiring the communication neighbor information, the network entry comprising: the site address identification in the network is used for establishing a relay routing relationship, managing the relay routing relationship of subordinate sites, supporting a white list management mechanism of a local communication network, allowing white list addresses to access the network and eliminating sites which are not in the white list address range.

8. A cooperative neighbor discovery and access control protocol based on electric broadband carrier according to claim 7, further comprising networking after the networking, wherein the networking comprises one-level site networking and multi-level site networking.

9. The cooperative neighbor discovery and access control protocol over power broadband carriers of claim 8, wherein the primary site networking comprises: after a central coordinator in a broadband power line carrier communication network is powered on, a network networking process is started, and the central coordinator sends a central beacon in a beacon time slot to trigger a first-level station to access the network.

10. A cooperative neighbor discovery and access control protocol based on power broadband carrier according to claim 8, wherein the multi-level site networking comprises: after processing the association request of the site, the central coordinator firstly carries the processing result in the generated association confirmation message, sends the association confirmation message to the agent site of the site in a one-by-one forwarding mode, and then informs the site of the network access request in a broadcasting mode by the agent site; and after the station successfully accesses the network, the station is added into the accessed network queue.