Lightweight multicast acknowledgement technique in communication networks

An apparatus, comprising:

• one or more network interfaces that communicate with a network;
• a processor coupled to the one or more network interfaces and configured to execute a process;
• and
• a memory configured to store program instructions which contain the process executable by the processor, the process comprising:
• receiving, as a caching node in the network, a message including an indication of the message's urgency;
• transmitting the message to child nodes of the caching node;
• in response to the message including an indication that the message is urgent:
• initiating a retransmission timer upon transmitting the message when the message is urgent, based on the indication of the message's urgency;
• caching the message at the caching node;
• receiving one or more acknowledgements of receipt of the transmitted message from one or more of the child nodes, respectively;
• monitoring received acknowledgements using a bit vector-type data structure and
• retransmitting the cached message to the child nodes when, upon expiration of the retransmission timer, it is determined that one or more of the child nodes did not receive the transmitted message based on the monitored received acknowledgements.

A tangible non-transitory computer readable medium storing program instructions that cause a computer to execute a process, the process comprising:

• receiving, at a caching node in a network, a message including an indication of the message's urgency;
• transmitting the message to child nodes of the caching node;
• in response to the message including an indication that the message is urgent:
• initiating a retransmission timer upon transmitting the message when the message is urgent, based on the indication of the message's urgency;
• caching the message at the caching node;
• receiving one or more acknowledgements of receipt of the transmitted message from one or more of the child nodes, respectively;
• monitoring received acknowledgements using a bit vector-type data structure;
• and
• retransmitting the cached message to the child nodes when, upon expiration of the retransmission timer, it is determined that one or more of the child nodes did not receive the transmitted message based on the monitored received acknowledgements.