Bandwidth Efficient Frame Design

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Bandwidth Efficient TCP Frame Design without Acknowledgment Number field

Abstract. This paper presents a novel design of a TCP frame. Unlike the original design, proposed design does not include 32 bit acknowledgment number field. This modified TCP design is discussed with the help of state diagrams, pseudo code, general equations and computer simulations. A comparison is then made between suggested and original design for simplex, duplex and pipelined case. The result clearly indicates that our design provides same kind of functionality for any case but with reduced header size. This reduction of header size decreases transmission time, increases bandwidth efficiency which in return increases throughput. Key words: TCP, Simplex, Duplex, Pipelining

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Introduction

TCP provides core functionality for almost every application running on any kind of network. The Transmission Control Protocol (TCP) is the de-facto standard used by the internet community to handle bulk transfers [1]. Transmission control protocol (TCP) has become the dominant communication protocol suite in todays multimedia applications [2]. From old but reliable Ethernet to complex sensor networks, reliability of efficient and accurate communication heavily depends on the performance of TCP. Communication networks have evolved greatly in the last decade [2]. An ignored factor affecting end-to-end TCP performance is the transmission time of ACK packets [4]. The influence of ACK packets on the throughput is also usually neglected when analyzing TCP [3], [4], [5] due to its small size compared to DATA packets. Reducing the size of header but keeping the original functionality in place is achieved by our new design that is proposed in this research paper. It does not involve any complex algorithms rather some small but intelligent modifications, at sender and receiver end, have made it possible. Careful designing assures that all the functionality that was with the acknowledgment field is still there with reduced header size even if the field is removed in our new design.

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Bandwidth Efficient TCP Design without Acknowledgment Number field

The paper is organized as follows: Section 2 presents the Modified TCP Frame structure, Sender and Receiver design for the modified system, Section 3 presents the TCP frame design for simplex system, Section 4 presents the TCP frame design for Duplex and pipelined Duplex system, Section 5 presents Conclusion remarks

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Modified TCP Frame Structure without Acknowledgment Field

In this research paper we present a new design for TCP frame that does not include Acknowledgment Number field. We save 32 bits in each packet which were used for acknowledgment in original design. With this design we can save thousands of bits for a large file. Original design and modified design is shown in Fig. 1 and Fig. 2 respectively.

Fig. 1. TCP Frame structure with 32 bit Acknowledgment number.

Fig. 2. TCP Frame structure without 32 bit Acknowledgment number.

2.1

Receiver Design for TCP without Acknowledgment

Acknowledgment number is used to notify sender that data has been received successfully. We have therefore kept the functionality of acknowledgment in our

Bandwidth Efficient TCP Design without Acknowledgment Number field

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new design even if the 32 bit acknowledgment field is removed. We achieve so by introducing two timers, one at sender and other at receiver end. Since acknowledgment field is removed, we use one bit ACK flag for a new purpose. Two events that can occur at receiver are: Packet Received Successfully: A timer is placed at receiver. Transport Layer at receiver end receives packet from lower layers. In case of successful transmission receiver does not notify sender. Receiver simply extracts data, stop timer for received packet and start new timer for next packet. Packet Received Unsuccessfully: In case if packet is lost or received in corrupted form the receiver discard corrupted packet and wait for...
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