The lower layers of the 150 ne

Many applications might not require reliable message delivery.For instance,a coded video stream could recover from packet losses by performing interpolations to derive lost data.In fact,in such applications,retransmitted data is of little use since they would arrive much later than the optimal time and not conform to realtime guarantees.For such applications,reliable message delivery at the lowest level is an unnecessary feature and might result in increased message traffic, most of which is useless,thereby resulting in performancedegradation.

In general,the lowest levels of the networking stack needs to support the minimal amount of functionality required by all applications and leave extra functionality to be implemented at the upper layers.