Large propagation delay, low bandwidth, frequent loss of connectivity, variability of sound speed, limitation on source of energy, etc. are the key challenges, which are identified as necessary issues for establishing efficient and reliable UWSN.
The heterogeneity of MANETs makes end-to-end support for quality of service (QoS) guarantees more difficult than in other types of networks, not to mention the limited bandwidth and frequent topology changes of these networks.
Design of protocols for mobile ad-hoc networks (MANETs) is generally tricky compared to wired networks, because on the one hand the increased communication constraints given by the limited bandwidth and frequent network failures, and on the other hand the additional computation and memory constraints due to performance limitations of mobile devices must be considered.
Mobility, frequent handoffs and limited bandwidth are important constraints for QoS in wireless networks.
Taking the relay ability into account, each node is allocated to the P2P multicast topology to minimize negative effects caused by the dynamic change of available bandwidth and frequent disconnection.
However, frequent peer churn and varying bandwidth of peer nodes in P2P networks pose significant challenges for video streaming.
Guaranteeing QoS in wireless networks is a complicated task due to the unique characteristics of wireless networks such as user mobility, limited link capacity, frequent link failure, scarcity of bandwidth, channel fading, and inability to predict the availability of resources in the network.
Two frequent measures are the memory bandwidth and memory access latency.
In some areas, the network has less bandwidth and even frequent disconnections.
Though high quality images are typically around 1 Mbytes, slide change is not that frequent that would cause high bandwidth utilization.
