The next generation of networks must support billions of connected devices in the Internet-of-Things (IoT). To support IoT applications, sources sense and send their measurement updates over the Internet to a monitor (control station) for real-time monitoring and actuation. Ideally, these updates would be delivered at a high rate, only constrained by the sensing rate supported by the sources. However, given network constraints, such a rate may lead to delays in delivery of updates at the monitor that make the freshest update at the monitor unacceptably old for the application.
Age Control Protocol+ (ACP+) is a novel transport layer protocol,that enables timely delivery of such updates to monitors, in a network-transparent manner. ACP+ allows the source to adapt its rate of updates to dynamic network conditions such that the average age of the sensed information at the monitor is minimized.
ACP+ is published at IEEE INFOCOM AOI Workshop 2021
T. Shreedhar, S. K. Kaul and R. D. Yates, "An Empirical Study of Ageing in the Cloud," IEEE INFOCOM 2021 - IEEE Conference on Computer Communications Workshops (INFOCOM WKSHPS).
ACP (previous version of this code) was published in IEEE WoWMoM 2019
T. Shreedhar, S. K. Kaul and R. D. Yates, "An Age Control Transport Protocol for Delivering Fresh Updates in the Internet-of-Things," 2019 IEEE 20th International Symposium on "A World of Wireless, Mobile and Multimedia Networks" (WoWMoM), 2019, pp. 1-7, doi: 10.1109/WoWMoM.2019.8793011.
The Age Control Protocol+ resides in the transport layer of the TCP/IP networking stack and operates only on the end hosts. ACP+ also uses the user datagram protocol (UDP) for sending of updates generated by the sources, inline with the freshness requirements of the updates.
The client appends a header to an update from a source. The header contains a timestamp field that stores the time the update was generated. The source ACP+ calculates the inter-update generation rates using the estimated network conditions over the end-to-end path to the monitor ACP+. For this, monitor sends an ACK which contains the timestamp of the update being acknowledged. The ACK(s) allow the source ACP+ to keep an estimate of the age of sensed information at the monitor. Out-of-order packets and ACK(s) are discarded from the calculations.
For establishing an ACP+ connection, the monitor/server ACP+ must be listening on a previously advertised UDP port. The ACP+ client/source establishes a UDP connection with the server, and sends an update and waits for an ACK or for a suitable timeout to occur, and repeats this process for a few times, with the goal of probing the network to set an initial update rate. ACP+ operation can be described by a sequence of control epochs. Please refer to the paper on details of how an update rate is set at a control epoch. An ACP+ end-to-end connection is closed when the source closes its corresponding UDP socket.
Following are the steps to run the codes in this repository :
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Create executables of C++ source code
g++ -std=gnu++11 client_acp.cpp -o client_acp -lpthread -lrtg++ -std=gnu++11 client_baseline.cpp -o client_baseline -lpthread -lrtg++ -std=gnu++11 server.cpp -o server -lpthread -lrt -
Run server on a machine and pass a port number along with it
./server $port -
Run client on a different machine and pass a port number along with it. You can run the ACP and baseline on a single machine.
./client_acp $serverIP $packetSize $numPackets 2 $stepSize $port./client_baseline $serverIP $packetSize $numPackets 2 $port
Flags: $serverIP→ IP address of ACP+ server $packetSize → Packet size of the UDP packet (bytes) $numPackets → Total number of packets that the client sends $stepSize → Step size used in the control block. Use 100 for step size 1. $port → UDP port for ACP+ client server