QoS Strategies for Wireless Multimedia Sensor Networks in the Context of IoT at the MAC Layer, Application Layer, and Cross-Layer Algorithms

Table 4

A summary of some of the reviewed cross-layer models.

Protocol	Layers	Aims	Comments	QoS parameters
SDRCS	MAC/PHY	Routing real-time traffic	Transmits multimedia traffic via cross-layer packet forwarding	Throughput, latency
SUIT	Application/transport	Transmission of non-real-time video	Uses fuzzy logic to regulate congestion	Transmission rate, delay
CLASS	Any two	Design serves as a framework for different implementations of different application scenarios	Scalable, very efficient, flexible, and has very low propagation delay	Propagation delay, jitter
NLQS	PHY/MAC/network	Permits packet-level service differentiation as a function of throughput, packet error rate, and delay	Network layer QoS is enhanced	Throughput, delay, packet error rate
CMVT	Application/network	Encodes video streams to video data frames via MPEG-4 encoding and does route discovery and data transfer	Greedy forwarding and rollback are used to find source-to-sink paths	Energy
CoopMAC	PHY/MAC	Offers spatial diversity among the three nodes	Helper ID signal finds out how feasible cooperative communication is	Throughput, rate, delay
M-CMAC	PHY/MAC	Increases end-to-end throughput and packet delivery ratio	Euclidean distances between nodes are calculated and converted to the data rate for a link	Throughput, packet delivery ratio
CBCR	PHY/MAC	Minimizes control overhead and time consumed in establishing the cooperative paths than M-CMAC	Energy consumption is more uniformly distributed in a network enhancing network lifetime	Throughput, packet delivery ratio, energy
MAC-PHY	MAC/PHY	Meant to enable PHY layer cooperation and maximize gains of cooperation at the MAC layer	Leverages both spatial diversity and coding gain	Throughput, delay
MAC-centric	MAC/APPL	Meant to support QoS needs in new video apps and enable MAC layer differentiation for H.264 partitioning	Targets multimedia applications by using the MPEG-4 scheme	Delay, packet loss rate
ACFEC	MAC/network (UDP)	Meant to enhance the quality of video streaming over 802.11 WLANs and overcome packet losses	Adjusts redundancy rates to overcome channel fluctuations and detect and reduce packet loss	Packet loss rate
MHDMwTS	—	Meant to provide reliable data transfer with the multipath routing and load-balancing congestion control method in WMSNs	More reliable than basic routing schemes for transport multimedia data	Latency, package transmit rate
BCFL	—	Introduces dispersion into fuzzy logic-based routing and sets every cross-layer parameter with a dynamic weight	Can be used to select a CH in cluster-based routing protocols and proposes a dispersion formula	Node utility, dispersion
CLOD	Datalink/network/transport	Prolongs network lifetime and achieves congestion control and designed for lightly loaded WSNs	Assumes fixed link capacity and integrates compressed sensing technology	Throughput, average energy, CS error ratio