In this paper we propose an integrated memory and disk 
cache for multimedia clients. The cache cushions the 
multimedia decoder from input rate fluctuations and 
mismatches, and because data can be cached to disk,
the acceptable fluctuations can be very large.
This gives the media server much greater flexibility
for load balancing, and lets the client operate efficiently
when the network rate is much larger or smaller than 
the media display rate.  We analyze the memory requirements 
for this cache, and analytically derive safe values for 
its control parameters.  Using a realistic case study, 
we examine the interaction between memory size, peak input 
rate, and disk performance, and show that a relatively 
modest amount of main memory can support a wide range 
of scenarios.