DMT Optimal Cooperative Protocols with Destination-Based Selection of the Best Relay

We design a cooperative protocol in the context of wireless mesh networks in order to increase the reliability of wireless links. Destination terminals ask for cooperation when they fail in decoding data frames transmitted by source terminals. In that case, each destination terminal D calls a specific relay terminal B with a signaling frame to help its transmission with source terminal S. To select appropriate relays, destination terminals maintain tables of relay terminals, one for each possible source address. These tables are constituted by passively overhearing ongoing transmissions. Hence, when cooperation is needed between S and D, and when a relay B is found by terminal D in the relay table associated with terminal S, the destination terminal sends a negative acknowledgment frame that contains the address of B. When the best relay B has successfully decoded the source message, it sends a copy of the data frame to D using a selective decode-andforward transmission scheme. The on-demand approach allows maximization of the spatial multiplexing gain and the cooperation of the best relay allows maximization of the spatial diversity order. Hence, the proposed protocol achieves optimal diversitymultiplexing trade-off performance. Moreover, this performance is achieved through a collision-free selection process

Solution for TCP/IP Flooding

TCP stands for transmission control protocol. It was defined by Internet Engineering Task Force (IETF). It is used in establishing and maintaining communication between applications on different computers and provide full duplex acknowledgement and flow control service to upper layer protocol and application. [2][3][4][5] In this report proposes solution for TCP SYN flood

DMT Optimal On-Demand Relaying for Mesh Networks

This paper presents a new cooperative MAC (Medium Access Control) protocol called BRIAF (Best Relay based Incremental Amplify-and-Forward). The proposed protocol presents two features: on-demand relaying and selection of the best relay terminal. “On-demand relaying” means that a cooperative transmission is implemented between a source terminal and a destination terminal only when the destination terminal fails in decoding the data transmitted by the source terminal. This feature maximizes the spatial multiplexing gain r of the transmission. “Selection of the best relay terminal” means that a selection of the best relay among a set of (m-1) relay candidates is implemented when a cooperative transmission is needed. This feature maximizes the diversity order d(r) of the transmission. Hence, an optimal DMT (Diversity Multiplexing Tradeoff) curve is achieved with a diversity order d(r) = m(1-r) for 0 ≤ r ≤ 1

Intelli MAC Layer Protocol for Cognitive Radio Networks

According to the FCC (Federal Communications Commission) [11], the utilization of the spectrum has been increasing rapidly over a wide range of frequency bands. There are various reasons that cause this dynamic growth. One reason is increase in network capacity. Another reason is increase in mobile services needed to carry over the spectrum. In order to overcome the shortage of spectrum due to increased usage, Cognitive Radio (CR) technology has been introduced. Cognitive Radios can utilize idle spectrum holes that are not occupied by the Primary Users (PUs) for performing temporary wireless communication tasks. PUs are licensed users which own and have access to certain spectrum bands. Challenging issues that need to be addressed by the CRs are spectrum sensing, spectrum sharing, spectrum management and spectrum mobility. The main contribution of this thesis is to design a new MAC layer protocol in order to determine the behavior of Secondary Users (SUs) based on PUs transmission history while taking into account both PUs and SUs. SUs are non licensed users which transmit only on those spectrum bands that are unutilized by the PUs. SUs usually observe the activity of PUs on spectrum bands. This new protocol allows the CR nodes to sense, share and manage access of the nodes to the spectrum. This protocol prevents any damage caused by SUs to the PUs transmission. Also, the new MAC protocol will negotiate the spectrum by assisting the CRs to identify the underutilized spectrum based on channel conditions such as channel throughput, channel data rate, channel score, channel utilization and packet error rate (PER). The Intelli MAC layer protocol measures transmission time among PUs and reduces channel sensing time for SUs. For managing the entire network, this protocol uses the concept of Harmonious Channel (HC). This protocol uses multiple half duplex transceivers for carrying data communication among users

Solution for TCP/IP Flooding

TCP stands for transmission control protocol. It was defined by Internet Engineering Task Force (IETF). It is used in establishing and maintaining communication between applications on different computers and provide full duplex acknowledgement and flow control service to upper layer protocol and application. [2][3][4][5] In this report proposes solution for TCP SYN flood

Pipelining protocols in TCP

Transmission Control Protocol (TCP), the most popular transport layer communication protocol for the Internet.It was originally designed for wired networks, where Bit Error Rate (BER) is low and congestion is the primary cause of packet loss [1].This article analyzes handshaking issues and pipeline protocols, such as slow start, congestion control, collisions, low BER etc. Then it provides pipeline protocols to wireless network i.e., Head of Line Blocking. At the end it proposes solution for TCP enhancement specific to wireless network