Fig. 1. Comparison based on average link occupancy: Multicast gain η^mc (left-hand-side) and broadcast-unicast gain η^bc (right-hand-side) as a function of the shape parameter α for link capacities C=20,100,500 (panels from top to bottom). Curves within panels correspond to content population sizes I=C+1,(5/4)C,2C,10C,∞ (curves from top to bottom).

Fig. 2. Blocking probabilities and as functions of the number of broadcast contents I^bc in the case C=100, I=∞, α=1.4, N=4700, and p=0.1. The optima have been marked.

Fig. 3. Comparison based on average content-wise call blocking probability: multicast gain η^mc (left-hand-side) and broadcast-unicast gain η^bc (right-hand-side) as a function of the shape parameter α for link capacities C=20,100 (panels from top to bottom). Curves within panels correspond to content population sizes I=C+1,(5/4)C,2C,10C,∞ (curves from top to bottom). For C=100, the highest curve is not visible.

Fig. 4. Comparison based on worst content-wise call blocking probability: Multicast gain η^mc (left-hand-side) and broadcast-unicast gain η^bc (right-hand-side) as a function of the shape parameter α for link capacities C=20,100 (panels from top to bottom). Curves within panels correspond to content population sizes I=C+1,(5/4)C,2C,10C,∞ (curves from top to bottom).

Fig. 5. Comparison based on time blocking probability in large systems: multicast gain η^mc (left-hand-side) and broadcast-unicast gain η^bc (right-hand-side) as a function of the shape parameter α for link capacities C=100,500 (panels from top to bottom). Curves within panels correspond to content population sizes I=C+1,(5/4)C,2C,10C,∞ (curves from top to bottom).

Fig. 6. The transmission mode to be used for content distribution depends on the Zipf parameter α and on the link capacity C. Left: the average content-wise call blocking probability criterion is used, right: the worst content-wise call blocking probability criterion is used.

The required α for gain η=4 with I=∞ and p=0.1