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Multi-Antenna Communication Security with Deep Learning Network and Internet of Things
Published in Sudhir Kumar Sharma, Bharat Bhushan, Aditya Khamparia, Parma Nand Astya, Narayan C. Debnath, Blockchain Technology for Data Privacy Management, 2021
Garima Jain, Rajeev Ranjan Prasad
For multi-antenna telecommunications systems, the base station uses limited protocols on the sender side for encoding, while the receiving end uses protocols to decode the message. MIMO antenna systems are among the most promising solutions to fulfill the demands of upcoming fifth-generation (5G) wireless mobile communication systems [10]. On the sender side, to start any kind of sending operation, the sender opens the host and port. If they are not available, then the process is terminated on both the host and the port sides. Once the host and port are available, then the string from the database is read by the reader. There are several receiving processes that occupy the value read from the database. Once this task is completed, the host and the port are closed. At the receiver end, the receiver’s local port is opened and starts the message receiving operation, using several routine processes. Once these routine processes receive them, the messages are stored in the database. An acknowledgement is sent to the sending operation that the messages have been received.
MAC and Network Layer Issues and Challenges for IoT
Published in Ricardo Armentano, Robin Singh Bhadoria, Parag Chatterjee, Ganesh Chandra Deka, The Internet of Things, 2017
Upena Dalal, Shweta Shah, Jigisha Patel
The MAC layer of IEEE 802.15.4 has the following features: association and disassociation, channel access mechanism, acknowledged frame delivery, frame validation, guaranteed time slot management, and beacon management. The MAC frame format of IEEE 802.15.4e is shown in Figure 3.5 that is almost the same as the general MAC of IEEE 802.15.4. There are four types of MAC frames: data frames, MAC command frames, acknowledgment frames, and beacon frames. The size of frame has to be less than 127 bytes considering the size constraint of the physical layer payload. The sequence number field is used to match the received acknowledgment frames. The frame check sequence is a 16 bit Cyclic Redundancy Checks (CRC). In the multipurpose format size of source, PAN identifier is varied. The multipurpose frame structure provides flexibility for the various purposes. Format supports short and long form of frame control field and allows for all MHR fields to be present or elided as specified by the generating service (IEEE 802.15.4, 2011; Montenegro et al., 2007; Patil and Lahudkar, 2016).
Networked Embedded Systems: An Overview
Published in Richard Zurawski, Networked Embedded Systems, 2017
The EIA-709 layer 4 supports four types of services. The unacknowledged service transmits the data packet from the sender to the receiver. The unacknowledged repeated service transmits the same data packet a number of times. The number of retries is programmable. The acknowledged service transmits the data packet and waits for an acknowledgement from the receiver. If not received by the transmitter, the same data packet is sent again. The number of retries is programmable. The requested response service sends a request message to the receiver; the receiver must respond with a response message, for instance, with statistics information. There is a provision for authentication of acknowledged transmissions, although not very efficient.
Fuzzy-based fault-tolerant and instant synchronization routing technique in wireless sensor network for rapid transit system
Published in Automatika, 2019
K. M. Karthick Raghunath, S. Thirukumaran
Finally for each message transmission, the sender gets acknowledgement from the receiver. Due to the permanent fault at the receiver side, if the sender does not receive any acknowledgement in a particular period, then it decides to route the packets through another optional NN. Hence, sender's short waiting period to receive the acknowledgement is termed as “critical time (CT)” Again sender performs the same slot assignment process with the newly preferred NN. On the completion of entire transmission between the sender and NN, again NN starts to forward the received packets towards CN by following the same slot assigning procedure. Thus, by tolerating the permanent fault, this mechanism ensures the effective end-to-end packet delivery with high probability. Figure 5 shows the diagrammatical description of the proposed work. Since most of the WSN-based RTS applications are the type of mission critical application, our proposed work is the right choice of adaptable form under various critical situations like collision, fire accidents, etc.
Dynamic speed adaptive classified (D-SAC) data dissemination protocol for improving autonomous robot performance in VANETs
Published in Automatika, 2019
Many protocols were presented in literatures to reduce the broadcast storm problem in a high-density network. These protocols can be typified into sender-oriented protocols and receiver-oriented protocols. In sender-oriented protocols, a sender node detects the relay nodes for broadcasting packets, whereas in receiver-based protocols, the receiver node takes decision whether to transmit the packets or not. In works [10–13], receiver-based broadcast protocols have been explained. In these types of protocols, all of the redundant broadcasts are not eliminated. In addition, as these protocols employ a probabilistic method, the reliability of the network is not ensured, particularly in the case of sparse network. Hence the receiver-based broadcast protocols do not suit well for VANET applications where reliability is momentous. In [14], a multipoint relay (MPR) broadcast protocol was presented. In [15], connected dominating set-based broadcast protocol is presented. In both of these works, the authors did not consider the node mobility while selecting the relay node. Therefore, the relay node selection process becomes sub-optimal and packet loss will occur due to the moving nodes. In work [16], the authors presented enhanced MPR broadcast protocol that allows only several relay nodes to rebroadcast a message. This protocol employs an acknowledgement method to note whether the message is received by all the selected receivers and retransmitted on the occurrence of packet loss. The strength of received signal is not taken into account in selecting the relay nodes. The performance of this protocol is reduced when fading happens. In addition, the receiving node should transmit acknowledgement signal to the source node. This problem leads to increased overhead in the high-density network. Sahoo et al. [17] presented a protocol in which the node located far away in the selected direction is chosen to rebroadcast the message. But in a fading channel, packet loss happens when this method is used. Hence many factors, such as inter-vehicle distance, mobility and signal strength, must be taken into account for selecting relay node. In a VANET broadcast, retransmission process is necessary due to some factors such as the moving vehicles, data collisions and random loss occurring in fading channel. In enhanced MPR broadcast protocol, a source node retransmits a message if a receiver node did not receive the message in a fixed time period. This state can be checked by the protocol with the help of explicit ACK messages. Hence, the overhead problem increases particularly in the case of high-density network. Hence, the MAC layer contention time at every node increases. Thus, more delay occurs and a message becomes useless though it is received after some time. Hence, a lightweight retransmission method is considered.