In many practical media streaming applications it is required that the data be 
partitioned into multiple contiguous source blocks; each block could then be 
encoded, e.g. using a forward-error correcting code (FEC) to protect against 
packet loss, or be encrypted for security.  It is clearly desired that the 
receiver be able to start playback of the stream as soon as possible, and be 
able to continue the playback uninterrupted.  We address the problem of the 
optimal trade-off between the maximum transmission rate and the start-up delay 
for the uninterrupted playback of the media stream.  For a content with variable
bit-rate (VBR) this is a non-trivial problem, where the particular choice of the
positions of source blocks determines the achievable startup-delay/maximum-rate
combination.  We introduce an analytical framework to consider the problem, and
give an efficient algorithm to determine the blocking points that achieve an 
optimal startup-delay/maximum-rate combination.