An update can be multicast to a number of client devices. By multicasting an update, the update can be concurrently distributed to a large number of client devices using a single network transmission. This greatly reduces the amount of time required to update the client devices as well as the amount of bandwidth that is required to transfer the update over the network. As part of this multicasting process, the client device, which may have missed a segment of the multicast, can request the missed segment. The missed segment can then also be multicast to eliminate or minimize the redundant transmission of the missed segment.