Design of Efficient Multicast Protocol for IEEE 802.11n WLANs and Cross-Layer Optimization for Scalable Video Streaming

NANO SCIENTIFIC RESEARCH CENTRE PVT.LTD.,  AMEERPET, HYD

WWW.NSRCNANO.COM, 09640648777, 09652926926

DOT NET PROJECTS LIST--2013

DOT NET 2013 IEEE PAPERS

Design of Efficient Multicast Protocol

for IEEE 802.11n WLANs and Cross-Layer Optimization for Scalable Video Streaming

Abstract:

            The legacy multicasting over IEEE 802.11-based WLANs has two well-known problems—poor reliability and low-rate transmission. In the literature, various WLAN multicast protocols have been proposed in order to overcome these problems. Existing multicast protocols, however, are not so efficient when they are used combining with the frame aggregation scheme of IEEE 802.11n. In this paper, we propose a novel MAC-level multicast protocol for IEEE 802.11n, named Reliable and Efficient Multicast Protocol (REMP). To enhance the reliability and efficiency of multicast services in IEEE 802.11n WLANs, REMP enables selective retransmissions for erroneous multicast frames and efficient adjustments of the modulation and coding scheme (MCS). In addition, we propose an extension of REMP, named scalable REMP (S-REMP), for efficient delivery of scalable video over IEEE 802.11n WLANs. In S-REMP, different MCSs are assigned to different layers of scalable video to guarantee the minimal video quality to all users while providing a higher video quality to users exhibiting better channel conditions. Our simulation results show that REMP outperforms existing multicast protocols for normal multicast traffic and S-REMP offers improved performance for scalable video streaming

Existing System:

            IEEE 802.11 wireless local area network (WLAN) has been one of the most popular wireless access technologies due to its advantages of the high data rate, low cost, and easy deployment. Recently, most mobile devices such as laptops, PDAs, and mobile phones equip the WLAN interface for low cost and high speed Internet connectivity. In IEEE 802.11n, the physical layer (PHY) data rate increases to 600 Mbps. Also IEEE 802.11nintroduces an enhanced medium access control (MAC) protocol in order to reduce MAC layer overhead. One of key MAC enhancements of 802.11n is the aggregate MAC protocol data unit (A-MPDU) aggregation, which maximizes the throughput at the MAC layer. With the successful deployment of IEEE 802.11 WLANs and increase in applications that require multicast services such as IPTV and Internet streaming, multicast communications over IEEE 802.11 WLANs have received much attention. However, there are two well-known problems in the multicast protocol of the IEEE 802.11 standard. First, multicast frames are transmitted as a simple broadcasting mechanism without acknowledgments from receivers. Due to the absence of automatic repeat request (ARQ) mechanisms, the reliability of multicast frames cannot be guaranteed, especially when the probability of collisions or bit errors is high. Second, a low and fixed transmission rate is used for multicast transmissions. Although there have been several rate adaptation mechanisms for uncast transmissions in WLANs, they cannot be directly applied to multicast transmissions since the sender does not receive any feedbacks from receivers.

Proposed System:

            In order to improve the reliability of multicast transmissions in WLANs, various ARQ mechanisms have been proposed. They can be classified into individual ARQ for each multicast receiver, uncast-like ARQ, and negative acknowledgment based (NAK-based) ARQ. Due to its effectiveness, the NAK-based ARQ mechanism is the most widely adopted to various 802.11 multicast protocols. In addition, for using the highest possible data rate enabling the provisioning of reliable multicast transmissions, several rate adaptation mechanisms have been proposed. In those mechanisms, the data rate is determined by either local acknowledgment information at the sender or explicit feedbacks from receivers. In this paper, we focus on multicast transmissions over 802.11n WLANs. Most of existing multicast protocols for WLANs have been designed based on the legacy 802.11 MAC. Since 802.11n MAC has a backward compatibility with the legacy 802.11 MAC, the existing multicast protocols can be used in 802.11n WLANs as well. However, unfortunately, the existing multicast protocols have serious problems in 802.11n WLANs when the A-MPDU aggregation is used for multicast transmissions. First, the reliable multicast protocols that use the NAK-based ARQ mechanism may result in unnecessary retransmissions for AMPDU frames. This is because the block acknowledgment mechanism for A-MPDU transmissions conflicts with the NAK-based ARQ mechanism. Besides, rate adaptation mechanisms used in existing multicast protocols cannot select appropriate data rates for A-MPDU transmissions

since they have been designed based on the legacy data transmission (i.e., single MPDU transmission.). In order to improve the performance of multicast services in IEEE 802.11n WLANs, we propose a novel MAC-level multicast protocol, named Reliable and Efficient

Multicast Protocol (REMP). By considering the A-MPDU aggregation, we introduce an advanced feedback mechanism for multicast transmissions. Basically, when the channel condition is stable, an AP exchanges control frames with a selected multicast receiver for each A-MPDU transmission. On the other hand, when the channel condition is dynamic, the AP exchanges control frames with all the multicast receivers. Based on feedbacks in the control frames, the AP selectively retransmits erroneous multicast frames and efficiently adjusts the modulation and coding scheme (MCS) under varying channel conditions. Although REMP can provide reliable multicast services to multicast receivers, it may heavily penalize receivers exhibiting better channel conditions. To handle this issue, we further consider the use of the scalable video coding technique that supports the flexible adaptation of video quality based on a hierarchical layer structure. In this paper, we extend REMP for scalable video streaming over IEEE 802.11n WLANs via cross-layer optimization. The extension of REMP, referred to as scalable REMP (S-REMP), aims at guaranteeing the minimal video quality to all users while providing a higher video quality to users exhibiting

better channel conditions. In S-REMP, different layers of scalable video are transmitted with different MCSs according to the network load..

Software and Hardware Requirements                    

Hardware Required:                            

System                                    :           Pentium IV

Hard Disk                   :           80 GB

RAM                           :           1GB

Software Required:

Operating System       :           Windows XP (Service Pack 3)

Language                    :           C# (Visual Studio 2010), HTML, XML

Modules:

·         Client Module

·         Server Module

·         Conversion (XML) module

·         HTML Module