A Comparison of Multicast Pull Models

We consider the setting of a web server that receivesrequests for documents from clients, and returns the requested documents over amulticast/broadcast channel. We compare the quality of service (QoS) obtainable by optimal schedules under various models of the capabilities of the server andthe clients to send and receive segments of a document outof order. We show that allowing the server to send segments outof order does not improve any reasonable QoS measure.However, the ability of the clients to receive dataout of order can drastically improve the achievable QoSunder some, but not all, reasonable/common QoS measures.