3.2.4 Higher-Layer Triggered Events

New blocks available: When the higher layer has new blocks in a segment to offer the hosted cache, it passes them to this protocol, along with the segment's associated content information and the content tag. The client SHOULD construct an INITIAL_OFFER_MESSAGE request message (section or BATCHED OFFER_MESSAGE request message (section that contains the segment HoHoDks, send it to the hosted cache, store it along with the content tag in its set of outstanding request messages, and start the request timer.

The higher layer SHOULD initiate the use of this protocol only when a sufficient number of new blocks have been received from the content server. Doing otherwise, such as initiating the protocol for every new block that becomes available, could lead to poor network performance.<9>