Acknowledgment Code (ACK) – Definition

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Acknowledgment Code (ACK) Definition

Acknowledgment Code, or ACK, refers to a service that is offered by mail companies to inform the sender of a letter that the recipient has received the delivery. It is usually a form signed by the receiver and then delivered to the sender. This gives proof to the sender that the letter has been received.

A Little more on What is Acknowledgment Code ACK

The legal regulations governing the concept of acknowledgment of receipt vary in different countries. However, in most states, the recipient must sign on a form after receiving the package. Nowadays, this procedure is being done by electronic means where the signature is made on a touch screen that captures even the date and the document number of the correspondence being sent.

If the recipient rejects the shipment and refuses to sign the ACK, a record of the refusal is input. If the post office sending the package loses the ACK, the client does not have the right to compensation. However, a duplicate may be issued if the issuer requests it and it must be signed again by the recipient or contain a written statement from the postman who made the delivery

Sometimes, the acknowledgment can be a brief response from a recipient after receiving a communication. This type of acknowledgment is usually delivered by large companies or state agencies where a person in contact with the other party is awaiting confirmation.

For example, suppose that a citizen sends a letter to the city’s secretary of the environment about the improvement of the cleaning of a beach. After a few days, an official returns a message of acknowledgment citing that they have received the request and they are addressing the situation.

In various communication protocols between computers, an ACK is a notice sent by one computer to another acknowledging that it has received the message from it. This type of ACK is mostly used in the layers or levels forming a network such as those in the open systems interconnection model.

The messages sent between computers may also have an error-detecting code to protect the data’s integrity. If the destination device of the message has the necessary tools to carry out this process, the ACK then can be a record of the state in which the message was received, i.e., whether it arrived without errors or not.

When the communication protocols are of greater complexity, additional elements such as data concerning incidents in the network or the request of forwarding some frames can be part of the message.

References for Acknowledgement Code ACK

Academic Research on Acknowledgement Code ACK

  • A low complexity protocol for relay channels employing rateless codes and acknowledgment, Liu, Y. (2006, July). In Information Theory, 2006 IEEE International Symposium on (pp. 1244-1248). This paper provides a low complexity communication protocol for the relay channels that significantly achieve a reliable rate even when a code spans only finite numbers of fading blocks on average.
  • Forward Acknowledgment: Refining TCP congestion control, Mathis, M., & Mahdavi, J. (1996, August). In ACM SIGCOMM Computer Communication Review (Vol. 26, No. 4, pp. 281-291). ACM. This paper focuses on the developed Forward Acknowledgement (FACK) congestion control algorithm which addresses multiple performance problems observed on the internet.
  • Issues in the implementation of selective acknowledgments for TCP, Rizzo, L. (1996). Draft report. Information is available at http://info. iet. unipi. it/luigi/sack. Html. This paper investigates the effectiveness of selective acknowledgment (SACK) options for TCP since it is expected that when a SACK mechanism is combined with suitable congestion control, it is capable of improving TCP performance over lossy networks.
  • Triple-receiver-based code protocol for unslotted DS/SSMA packet-radio networks and its performance analysis, Chen, X. H., & Lim, N. C. (1995). IEE Proceedings-Communications, 142(3), 193-200. This paper proposes the use of an unslotted DS/SSMA packet-radio protocol suitable for code-division multiple-access wireless data networks. It initiates the communication between two data terminals through hand-shake which is followed by the transmission of data-packet and uses the receiver-based signature codes for multiple-accessing.
  • Visual communication system in an apartment house using only twisted paired cable Kato, M., Kamimura, T., & Kumagai, A. (1994). IEEE Transactions on Consumer Electronics, 40(3), 418-427. This paper shows the visual communication systems of an apartment house, constructed of the Home Bus and a network, can be used in an apartment complex.
  • Description and formal specification of the link layer of P1394, Luttik, S. P. (1997, June). In Proceedings of the 2nd International Workshop on Applied Formal Methods in System Design, Zagreb (pp. 43-56). This paper describes the P1394 link layer and then gives a formal specification of the same.
  • Challenge-response based ACK message authentication, Park, M. H. (2012). Electronics Letters, 48(16), 1021-1023. This paper explains that while ACK should be short because it is just a notice of a successful receipt, the size of the ACK packets increases due to a message header or security options.
  • An approach to secure communication in mobile ad-hoc networks of Android devices, Alam, T., & Aljohani, M. (2015, November). In 2015 International Conference on Intelligent Informatics and Biomedical Sciences (ICIIBMS) (pp. 371-375). IEEE. An algorithm on mobile android devices is proposed in this paper for secure communication of wireless ad hoc networks. The major issues concerning this approach provide the security analysis for communication among ad hoc network.
  • Several secure store and forward devices, Goldschlag, D. M. (1996, January). In Proceedings of the 3rd ACM Conference on Computer and Communications Security (pp. 129-137). ACM. This paper describes the secure store and forward devices that can be used to move data from LOW to HIGH without human intervention.

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