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7/31/2019 Gl 2311161122 http://slidepdf.com/reader/full/gl-2311161122 1/7 Harsharndeep Singh, Meenu Dhiman, Pankaj Kumar Sehgal / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com  Vol. 2, Issue 3, May-Jun 2012, pp.1116-1122 1116 | P age A Survey on Video Streaming Schemes over MANETs Harsharndeep Singh * Meenu Dhiman** Pankaj Kumar Sehgal** M.Tech Scholar I.T. Deptt. I.T. Deptt. I.T. Deptt., MMU Mullana MMU, Mullana MMU, Mullana  Abstract  —  Real time video streaming over wireless networks is an increasingly important and attractive service to the mobile users. Video streaming involves a large amount of data to be transmitted in real time, while wireless channel conditions may vary from time to time. It is hard to guarantee a reliable transmission over the wireless network, where the parameters specifying the transmissions are; bandwidth, packet loss, packet delays, and outage times. The quality of the video is affected negatively when network packets are lost, and the mobile users may notice some sudden stop during the video playing; the picture is momentarily frozen, followed by a jump from one scene to a totally different one. In this paper, a survey on different issues and analysis of proposed techniques for video streaming over MANETs is presented. This survey paper analyzes different schemes for video streaming in MANETs i.e. cross-layer design schemes, multiple description coding (MDC) schemes and multipath routing schemes. Keywords:  MANETs, Video Streaming, cross- layer design, MDC, Multipath routing. 1. INTRODUCTION MANETs does not have any fixed infrastructure, so the mobile nodes are free to move within a network which results in dynamic change of network topology. Other MANETs issues are limited bandwidth, lack of centralized monitoring, cooperative algorithms, limited physical security, energy constrained operations, etc. Ad-Hoc networks are categorized into two types of routing protocols, i.e. Table-driven routing protocols and On-demand routing protocols. Table-driven routing protocols are also known as pro-active routing protocols. These protocols attempt to maintain an updated routing table with routes to all known destination nodes in the network. This has the advantage of minimizing the delay during routes lookup and the disadvantage of these protocols is that it consumes a lot of network bandwidth. Whereas On-demand routing protocols only update the routing table in response to a routing request. This has the advantage of minimizing network traffic overhead and disadvantage of these protocols is increased delay.Video streaming in MANETs [1] is one of the most challenging issues. Video streaming in MANETs is mainly affected by these factors like node mobility, dynamic change in topology, multi path shadowing and fading, collusion, interference and many more. The dynamic change in topology causes periodic connectivity which results in large packet loss. Packet loss has the largest impact on the quality of the video. Video streaming in real time requires special techniques that can overcome the losses of packets in the unreliable networks. The paper is organized as follows. Section 1 discusses the introduction to MANETs and video streaming. Section 2 presents video streaming issues for MANETs. Section 3 presents different schemes for video streaming. Section 4 presents the conclusion. 2.  VIDEO STREAMING ISSUES There are several aspects of mobile ad-hoc networks that complicate the issues of video streaming. These aspects are:-  Wireless medium: Operating on a wireless medium, MANETs are susceptible to the traditional problems with wireless communications. Wireless transmissions are susceptible to various transmission errors, caused by interference from other electrical equipment, multi-path fading, or colliding transmissions by other nodes. Recovering from such errors may require retransmission of data. This leads to an increase in delay and jitter, impacting the quality of the multimedia stream. Each node has a limited transmission range. This range is dependent upon many factors, such as the wireless transmission protocol, antennae size, energy use, obstacles and weather conditions. This limited range means that data must be routed through several other nodes to reach the destination. Each hop adds processing delay and increases the possibility of introducing a

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Harsharndeep Singh, Meenu Dhiman, Pankaj Kumar Sehgal / International Journal of Engineering Research and Applications (IJERA)

ISSN: 2248-9622 www.ijera.com Vol. 2, Issue 3, May-Jun 2012, pp.1116-1122 

1116 | P a g e

A Survey on Video Streaming Schemes over MANETs

Harsharndeep Singh * Meenu Dhiman** Pankaj Kumar Sehgal**M.Tech Scholar  I.T. Deptt.  I.T. Deptt. 

I.T. Deptt., MMU Mullana  MMU, Mullana MMU, Mullana

 Abstract —  Real time video streaming over wireless networks

is an increasingly important and attractive service

to the mobile users. Video streaming involves a

large amount of data to be transmitted in real

time, while wireless channel conditions may vary

from time to time. It is hard to guarantee a

reliable transmission over the wireless network,

where the parameters specifying the transmissions

are; bandwidth, packet loss, packet delays, and

outage times. The quality of the video is affectednegatively when network packets are lost, and the

mobile users may notice some sudden stop during

the video playing; the picture is momentarily

frozen, followed by a jump from one scene to a

totally different one. In this paper, a survey on

different issues and analysis of proposed

techniques for video streaming over MANETs is

presented. This survey paper analyzes different

schemes for video streaming in MANETs i.e.

cross-layer design schemes, multiple description

coding (MDC) schemes and multipath routing

schemes.

Keywords:  MANETs, Video Streaming, cross-

layer design, MDC, Multipath routing.

1.  INTRODUCTIONMANETs does not have any fixed infrastructure, so

the mobile nodes are free to move within a network 

which results in dynamic change of network 

topology. Other MANETs issues are limited

bandwidth, lack of centralized monitoring,

cooperative algorithms, limited physical security,

energy constrained operations, etc. Ad-Hoc networks

are categorized into two types of routing protocols,

i.e. Table-driven routing protocols and On-demandrouting protocols. Table-driven routing protocols are

also known as pro-active routing protocols. These

protocols attempt to maintain an updated routing

table with routes to all known destination nodes in

the network. This has the advantage of minimizing

the delay during routes lookup and the disadvantage

of these protocols is that it consumes a lot of network 

bandwidth. Whereas On-demand routing protocols

only update the routing table in response to a routing

request. This has the advantage of minimizing

network traffic overhead and disadvantage of these

protocols is increased delay.Video streaming in

MANETs [1] is one of the most challenging issues.

Video streaming in MANETs is mainly affected by

these factors like node mobility, dynamic change in

topology, multi path shadowing and fading,collusion, interference and many more. The dynamic

change in topology causes periodic connectivity

which results in large packet loss. Packet loss has the

largest impact on the quality of the video. Video

streaming in real time requires special techniques that

can overcome the losses of packets in the unreliable

networks. The paper is organized as follows. Section

1 discusses the introduction to MANETs and video

streaming. Section 2 presents video streaming issues

for MANETs. Section 3 presents different schemes

for video streaming. Section 4 presents the

conclusion.

2.  VIDEO STREAMING ISSUESThere are several aspects of mobile ad-hoc networks

that complicate the issues of video streaming. These

aspects are:-

  Wireless medium: Operating on a wireless

medium, MANETs are susceptible to the

traditional problems with wireless

communications. Wireless transmissions are

susceptible to various transmission errors, caused

by interference from other electrical equipment,

multi-path fading, or colliding transmissions by

other nodes. Recovering from such errors may

require retransmission of data. This leads to an

increase in delay and jitter, impacting the quality of the multimedia stream. Each node has a limited

transmission range. This range is dependent upon

many factors, such as the wireless transmission

protocol, antennae size, energy use, obstacles and

weather conditions. This limited range means that

data must be routed through several other nodes to

reach the destination. Each hop adds processing

delay and increases the possibility of introducing a

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Harsharndeep Singh, Meenu Dhiman, Pankaj Kumar Sehgal / International Journal of Engineering Research and Applications (IJERA)

ISSN: 2248-9622 www.ijera.com Vol. 2, Issue 3, May-Jun 2012, pp.1116-1122 

1117 | P a g e

bottleneck into the network path. For each hop,

there is also the added possibility of a transmission

error occurring, which adds delay and increases

 jitter.

  Resource constraints: The devices participating in

a MANET will predominantly be small devices,which imply limited processing power, memory

and storage capacity. Being small mobile devices,

they will normally be battery powered, which

means energy consumption must be kept at a

minimum. Wireless communication will often

mean limited bandwidth, and as mentioned, the

nature of wireless communications means that this

bandwidth is shared by all devices in the

surrounding area. Additionally, an increase in

network traffic places additional load on the nodes

in the network, which in turn increases energy

consumption. It is therefore important to keep

network traffic overhead at a minimum.  Heterogeneity: While most or all of the nodes in a

MANET will have some resource constraints

imposed on them, the capabilities and resources of 

each node can be very varying. A laptop computer,

for example, has several times the processing

power and storage capacity of e.g. a cellular phone,

while a cellular phone has communication

capabilities usually not available to a computer.

Link bandwidth may also vary dramatically

depending on the type of wireless interface used

for communication.

  Lack of fixed infrastructure: The lack of a fixed

infrastructure requires that nodes function as

routers in the network. This can introduce large

bottlenecks, if a lot of responsibility is assigned to

a node with very limited resources.

  Topology changes: The node mobility leads to

continuous changes in topology, which means that

routes may be formed and broken rapidly. When a

route breaks, the discovery of a new route will

most likely introduce delays, which will affect the

quality of an ongoing media stream. In addition,

the topology change may introduce new bottleneck 

links in the network path, leading to a reduction in

bandwidth. In the worst case, parts of the network 

may even separate in such a way that there is no

route from one part of the network to another. Thisis known as partitioning. If source and destination

nodes wind up in separate partitions, the media

stream will be broken.

  Malicious nodes: There is also a real concern that

malicious nodes may delay or disrupt network 

traffic, by providing false routing information to

neighboring nodes. One type of malicious nodes

are so-called “lack holes”, that masquerade as a

bogus destination. Models show that using the

AODV routing protocol, if only 0.8% of nodes are

”black holes”, the resulting packet loss is close to

50%. If the fraction of “lack holes” increases to

4.0%, the resulting packet loss is close to 80%.

Such high packet losses would adversely affect amultimedia stream.

3. DIFFERENT SCHEMES FOR VIDEO

STREAMING This section consist different techniques for real-

time video streaming over MANETs.

3.1 CROSS LAYER DESIGN SCHEMES In cross layer design knowledge has been shared

between all layers to obtain the highest possible

adaptivity. Yang Xiao et al. [2, 3] propose a two-

level protection and guarantee mechanism for voice

and video traffic. This mechanism is basicallydesigned to control the number of collisions

independent of the number of active stations for data

transmission. This mechanism dynamically control

data traffic parameters based on data traffic load.

Number of rules are defined such as fast-back off,

dynamically adjusting parameters when fail,

dynamically adjusting parameters when consecutive

successful. In Fast-backoff: The proposed backoff 

method achieves a larger window size much quicker,

and becomes faster when the backoff stage is large,

when compared to the original binary exponential

backoff. Dynamically adjusting parameters when fail

rule: when a frame reaches the retry limit and is

dropped, some adjustments in parameters are made.

Dynamically adjusting parameters when consecutive

successful rule: when a station successfully transmits

m consecutive frames, the parameter adjustment are

made until the original low limit is reached. S.

Kompella et al. [4] proposed a Branch- and- Bound

method for solving optimization problems, especially

in discrete and combinatorial optimization. This

method use RLT to reformulate and linearize OPT-

MR into an LP relaxation L-MR. The optimal

solution to this LP relaxation provides a lower bound

LB for the original problem [5]. Since such an LP

relaxation usually yields an infeasible solution to the

original problem, a local search algorithm should beemployed to obtain a feasible solution to the original

problem. The resulting feasible solution then

provides an upper bound UB for the original

problem. Under branch-and-bound framework, the

original problem OPT-MR is partitioned into sub-

problems, each having a smaller feasible solution

space, based on the solution provided by the LP

relaxation. New sub-problem are organized as a

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Harsharndeep Singh, Meenu Dhiman, Pankaj Kumar Sehgal / International Journal of Engineering Research and Applications (IJERA)

ISSN: 2248-9622 www.ijera.com Vol. 2, Issue 3, May-Jun 2012, pp.1116-1122 

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branch-and-bound tree, while this partitioning or

branching process is carried out recursively to obtain

two new sub-problems at each node of the tree. In

this manner, the branch-and-bound process can

fathom certain nodes of the tree, eliminating them

from further exploration. The effectiveness of thebranch-and-bound procedure depends strongly on

that of the employed fathoming strategy. H. Wang et

al. [6] proposed a cross-layer optimized framework 

which jointly considers the video coding and

transmission in wireless mesh networks. This

solution makes use of dynamic programming to solve

the minimum distortion problem and provide the

optimal solution by using bisection method. The

Optimal Solution [7] for the Minimum Distortion

Problem: the minimum distortion problem, which is a

constrained optimization problem, can be

transformed into an unconstrained optimization

problem using the redefinition of the single-packetdelay. To solve the optimization problem, we define

a cost function Gk (vk −a, . . . , vk ) which represents

the minimum average distortion up to and including

the packet k  , given that vk −a, . . . , vk  are the

decision vectors for the packets (k − a) , . . . , k . Let O

be the total packet number of the video clip, and we

have O =  N ×I . Therefore, GO(vO−a, . . . , vO)

represents the minimum total distortion of the whole

video clip. The Optimal Solution for the Minimum

Delay Problem: for every given T p max, we can find

the parameter vector which results in  D∗(T p max),

the minimum average distortion of the whole video

clip, where each packet delay has to be below the

maximum delay T p max. we can use bisection to find

the optimal T ∗p max such that  D∗(T ∗p max) =  Ds

max, which solves the minimum delay problem .

Simulation results indicate that the proposed

framework has significant performance enhancement

over other systems where some system parameters

take fixed values. The performance gain is

significant, especially when the delay requirement is

stringent. Y. Mao et al. [8] propose a multimedia

network architecture that use slice priority of NAL

and partial checksum technique named ASIC. In

order to maintain better video quality for user, this

technique defines transmission priority so that the

video with higher priority data can be delivered first.To improve the throughput, partial checksum for

insensitive video data is calculated. The system

encapsulates sliced data into NAL-unit and partial

checksum is calculated for these sliced data by the

information stored in NAL header. The slice data

which is generated by VCL is the input of ASIC. The

advantage of this scheme is that when there is limited

bandwidth the transmission order is dependent on the

priority of slice. If every packet has same

transmission priority, then packet loss and delay time

causes video fragmentation [9]. In high bit error ratio

environment, the partial checksum can reduce error

video packet loss so that the throughput can be

improved. The multimedia network ASIC is designedin Verilog hardware description language and

synthesized by Synopsis using CCU 0.09 um CMOS

single-poly eight-metal standard cell library. The

proposed multimedia network ASIC operates faster

when compared to other networks. The system

achieves 14.58Gbps (455.8 MHz * 32bits) so that can

deal with 10Gbps fast Ethernet traffic. Besides, ASIC

supports NAL so that it is more suitable for

H.264/AVC streaming video delivery.

3.2 MULTIPLE DESCRIPTIONS CODING

SCHEMES 

Multiple descriptions coding (MDC) is a sourcecoding technique that generates multiple correlated

bit streams, each of which can be independently

encoded and decoded. Each bit stream, called a

description, is transmitted through the networks and

is expected to follow a different path to reach the

destination. The errors that could occur among

descriptions are independent and, hence, the

performance of MDC is maximal. Therefore, MDC is

considered as a promising technique to enhance the

error flexibility of a video transport system by

transmitting the video over multiple independent

channels like MIMO. The different techniques for

MDC are presented below in a chronological order.

Apostolopoulos [10] suggest to use two different

channels to transmit even and odd frames that will be

encoded by using Multiple Description Coding

(MDC)[11], he suggests that it can be beneficial to

transmit different amounts of traffic on different

channels. It may consist of two separate encoders and

decoders that alternate previous decoded frame it

uses to perform the prediction. If there are no errors

or frame losses and both even and odd streams are

received correctly, then both streams are decoded to

produce the full frames sequence for final display. If 

one stream has an error or frame losses then the state

for that stream is incorrect and there will be error

propagation for that stream. However, the otherindependently stream can still be accurately and

straightforwardly decoded to produce usable video.

Shiwen Mao et al. [12], proposed three MCP-based

video transport techniques for mobile ad hoc

networks. These schemes take advantage of path

diversity to get better performance. These three

schemes are based on the block-based hybrid coding

framework using MCP and discrete cosine transform

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(DCT), which is selected by all existing video coding

standards. The three techniques are (1) Feedback 

Based Reference Picture Selection (2) Layered

Coding with Selective ARQ. In Feedback Based

Reference Picture Selection, the reference frames are

selected based on feedback and predicted path status,the last frame that is selected to be correctly received

as the reference frame. In this technique the coded

frames are sent through the separate paths. The

mapping of frames depends on the bandwidth

available on each path. Decoder is assumed to send a

feedback message. If any packet in a frame is lost,

the decoder sends a negative feedback (NACK).

Otherwise, it sends a positive feedback (ACK). An

encoder receives the feedback message for frame n-

RTT when it is coding frame n, where round-trip

time (RTT) is measured in frame intervals. Once a

NACK is received form one path for a delivered

frame, the path is assumed to be “bad” until an ACK is received. Similarly, we assume that the path is in

“good” status until NACK is received. While

encoding a new frame, the encoder assume the last

accurately decoded frame, depend on the feedback 

messages received till this time, and uses that frame

as the reference frame. In Layered Coding with

Selective ARQ This scheme makes the use of layered

video coding. In this scheme, a raw video stream is

coded into two layers, a BL and an EL. A BL frame

is encoded using the standard predictive video coding

technique. That’s why BL has a lower coding

efficiency than a standard single layer coder. This

loss in coding efficiency is, however, justified by

increased error resilience: a lost EL packet will notaffect the BL pictures. Good quality is guaranteed if 

the BL packets are delivered error-free or at a very

low loss rate. Although this approach is optimal in

terms of coding efficiency for the enhancement layer,

error propagation can still occur in the EL pictures.

Tesanovic et al. [13], proposed a new scheme for

video transmission for efficient and robust video

streaming video over wireless channels, through a

combination of MIMO and MDC technology. Two

complementary MIMO techniques are used: space

time block coding[14] and spatial multiplexing. The

quality of the reconstructed video, already enhanced

 by the inherent MIMO systems’ properties, is further improved through the use of MDC. MDC has

evolved and has been adapted to lossy packet

networks. With correct design, MDC can exploit the

interactions between descriptions when losses occur

in multichannels wireless communications to reliably

recover to the video [15]. Lin et al. [16], investigate

the influence of two important characteristics on the

performance of the diversity level of the space time

code and the error resilient ability of the video coder.

For MIMO video system, the selection of diversity

levels and the selection of an error-resilient video

coder with appropriate redundancy are not

independent of each other. Where the video data need

to be lossy coded before transmission over threetransmitting and receiving antennas. The distortion

caused by the lossy source encoder directly depends

on the availability of the bit rates. Although a pace

time coder with full diversity can provide strongest

error protection of the source data, it usually supports

a lower bit rate, which means that the video encoder

can only output low-quality pictures. On the other

hand, a space time coder with maximum rate

(minimum diversity) allows the highest bit rate for

video coding, but its weak error correction ability

may cause devastating effects in the received video

quality. The results show that the appropriate source

coding and channel coding schemes depends on thechannel environment. Hence, to obtain the best

overall system performance, the source coding and

channel coding parameters need to be chosen jointly

and with regard to the channel quality. Joohee Kim et

al. [17], proposed a multipath video streaming [19]

framework using channel-adaptive MDC for efficient

video transmission. in this technique the sender sends

packets or information through different paths to the

receiver. Now the receiver will measure average

packet loss and the available bandwidth for those

different paths and sends the information back to the

sender. The proposed channel adaptive multiple

description coding algorithm generates two correlated

descriptions by adjusting its source coding bit ratesand the amount of MD coding redundancy according

to time-varying network conditions[18].

3.3 MULTIPATH ROUTING SCHEMES 

Routing is responsible to establish and maintain

possible end-to-end paths from source to

destination. The main challenge in video streams is

to classify the routes that ensure the video delivery

with a satisfying quality. In general, Multipath

routing can improve QoS by providing: - (i)

Accumulation of bandwidth and delay: breaking the

capacity of more than one route. (ii) Route load

balancing: balance the traffic load in highernumber of nodes.(iii) Fault tolerance: by adding

redundancy, to reduce the effect of network failures

onto affected video quality, it is important that the

paths are disjoint. In case the Multipath routing

protocol offers multiple paths with sufficient path

diversity, it is less probable that a link failure

affecting one of the paths simultaneously affects one

of the other paths. This is especially beneficial in

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real-time streaming, where the playback buffer is

limited and the video coder no longer can rely

only on time diversity. Johannes karlsson et al. [20,

21] proposed an error control method for real time

video streaming. In this technique, the reference

frame is considered as the last possibly correctdecoded frame. GloMoSim network simulator is

used for integrating the video codec because there is

a possibility of video frames loss. Which will

gradually effect the size of following video frames.

A new application layer is added as an interface to

the modified XviD video codec in the simulator.

They are connected using local sockets in Linux.

The simulator is event driven and will periodically

request a new video frame from the video codec. If a

packet is lost the simulator will also inform the

video codec about this. The modified XviD codec

stores some extra bits in the bit stream and is not

standard compliant. We send videos over a network simulator where we drop the packets randomly.

Different packet loss rates are tested, from 0% to

15% loss. This is tested for two different intra frame

intervals and for dynamic reference picture

selection. For the dynamic reference picture

selection there is no delay in the feedback. This

means that the encoder will know about a loss

before it encodes the next frame. If the feedback 

delay is increased the performance of dynamic

reference picture selection will decrease [22].Toby

Xu el at. [23] Proposed a proactive link protection

and receiver-oriented adaptation technique. Initially,

the source node discovers a route to its destination

node. After path discovery process source nodestarts to send data to the destination node. Initially

source node may need to set hop_cnt = 0 of a packet

and incremented each time when the packet is

retransmitted. And dest_pos field is used for

piggybacking the location of the destination node.

Whenever the destination node receives a packet, it

includes its current location in its ACK packet. This

location information is piggybacked to the source

node. Mobility of nodes may cause path burst which

results into streaming interruption. This problem is

undertaken by two new techniques [24].

  Proactive Link Protection: - it is aimed at

replacing a link that is about to break byproactively looking for an alternative one.

  Receiver-Oriented Adaptation: - The idea behind

this technique is making a straight path from

source to destination with minimum no. of hops.

In ideal case hop_cnt can be calculated using this

equation [L/R], where L is the length of the

connection line, and R is the transmission range.

Hamid Gharavi [25] proposed two multichannels

routing protocols. The first multichannels routing

protocol is based on single-path routing. This routing

protocol suppresses the intrapath interference in a

collision avoidance network or carrier sense multiple

access network [27]. The above routing protocol isdeveloped by using link-partitioning scheme where

the neighbor nodes operate at different non

overlapping frequency bands. A technique, named

systematic channel assignment, for this approach

shows that the partitioning scheme can substantially

amplifies the throughput performance of a multihop

link. The second multichannels routing protocol is

invented for transmission of real-time traffic over

multiple-path routes. In mobile ad hoc networks,

especially for real-time traffic, this approach can be

affected unfortunately from co-channel interference

due to the concurrent transmission of packets via

multiple routes. So a dual-path routing protocol isdeveloped, which guarantees a different frequency

band for each path, thus eliminating interpath

interference. This protocol reduces the possibility of 

losing all the routes at the same time. Both, dual-

description video coding [26] and the above

described routing protocols can enhance the

performance of real time video transmission over ad-

hoc networks. Monica et al. [28] proposed a

multipath [29] multimedia dynamic source routing

(MMDSR) technique. Initially the source sends a

Probe Message (PM) packet to destination through

each one of the paths discovered by DSR. A time-out

is triggered upon the arrival of the first PM packet at

destination. The PM packets received after timeoutare discarded, because these packets arrived through

a path having too much delay. After time-out, a Probe

Message Reply (PMR) packet generated by

destination node contains a set of sampled values of 

the QoS parameters collected from all the PM

packets that arrived in time. The PMR message is

sent back to the source through each one of the paths

through which a PM arrived. This information will be

analyzed at the source, where paths as categorized as

best_path, medium_path, wrost_path. Then, the

packets are sent according to their priorities as

highest priority packets through best_path, medium

priority through medium_path and lower prioritythrough wrost_path. 

4. CONCLUSION AND FUTURE WORKThis paper provides a classification and specification

of the challenges involved in video streaming over

MANETs and the techniques proposed to address

them. Since most solutions are based on cross layer

design, this paper gives an overview and analysis of 

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the combination of layers and the exchanged

parameters that are the most commonly used. This

survey shows that in general, currently existing

techniques tackle dynamicity and strict resource

constraints by jointly optimizing transmission

parameters at various layers of the protocol stack.Frequent path and transmission errors are handled by

adding redundancy, typically either by caching or

replication in an overlay, or by utilizing redundant

network routes. In order to select optimal

transmission parameters, it seems widely accepted

that cross-layer parameter exchanges are needed. Our

analysis unveils that 65% of the surveyed solutions

employ cross layering of some sort. Typically, the

application layer adapts the video stream bit rate

according to path characteristics obtained at the

network layer. Conversely, the network layer

discovers routes with end-to-end characteristics that

best suit the requirements of the video stream. It isbeneficial to combine multi stream coding techniques

(layered coding or MDC) with multiple routes.

Congestion is no longer handled entirely at the

transport layer, primarily because rate adaptation

should be handled by a flexible video codec.

Additionally, the aggregation of network resources

through the use of multiple routes, which in addition

adds path redundancy, calls for a transport protocol

that provides an adequate multipath interface to the

application. In terms of cross-layer optimization,

some works increase efficiency by including lower

link and physical layers in a more holistic cross-

layering approach. It is hence questionable whether

such complex systems will behave similarly whendeployed in real networks. This survey concludes that

few papers include enough information for the

experiments to be repeatable. Experimental results

are often difficult or impossible to compare, due to

the high variability of experiment parameter values.

There are still certain problems, which are yet to be

properly addressed. In MANETs, however, the

probability of the existence of such a path may be

low at any given point in time. Furthermore, mobility

can cause this connectivity to disappear and appear

frequently and unpredictably. Thus, server – client

connectivity throughout complete multimedia

sessions can be very improbable. If these sessionswere terminated whenever a partition occurs,

streaming across such networks would appear highly

impractical, no matter how well the system performs

end to end. More research is required to provide

delay-tolerant streaming solutions for MANETs

incorporating the above-mentioned mechanisms.

Altogether, realizing video streaming over MANETs,

there already exist many different types of techniques

to handle the challenges. Yet, there are many

unresolved issues to be addressed by future research.

REFERENCES[1] Tim Bohrloch,Carlos T. Calafate, A. Torres,

J.C.Cano, P.Manzoni, “Evaluating videostreaming performance in MANETs using a

testbed,” XXII Jornadas de Paralelismo , Sept.

2011

[2] Y. Xiao, H. Li, and S. Choi, “Protection and

Guarantee for Voice and Video Traffic in IEEE

802.11e Wireless LANs,” IEEE Infocom’04,

Hong Kong, pp. 2153-2163, Mar. 2004.

[3] Y. Xiao , “Backoff -based Priority Schemes for

IEEE 802.11,” IEEE ICC'O3. Anchorage. AK,

May 2003.

[4] S. Kompella, S. Mao, Y. Hou, and H. Sherali,

“Cross-layer optimized multipath routing for

video communications in wireless networks,”IEEE J. Select. Areas Commun., vol. 25, no. 4,

pp. 831 – 840, May 2007.

[5] J.Chakareski, S. Han, and B. Girod, “Layered

coding vs. multiple descriptions for video

streaming over multiple paths,” ACM

Multimedia, Berkeley, CA, pp. 422 – 431, Nov.

2003.

[6] Wu, D., Ci, S., Wang, H., “Cross-layer

optimization for packetized video

communications over wireless mesh networks,”

Proceedings of IEEE ICC 2008, pp. 1996 – 2000,

2008.

[7] Y. Wang, R.R Reibman and S. Lin, “Multiple

description coding for video delivery,” IEEE,

93(1), pp .57 – 70, Jan. 2005.

[8] Yi-Mao Hsiao, Feng-Pin Chang, Jai-Shiarng

Chen, Yan-Lin Su, Zhi-Wei Yang, Wei-Shan

Chen and Yuan-Sun Chu ”High Speed ASIC

Design of Multimedia” Network Industrial

Electronics and Applications (ICIEA), 5th

IEEE

Conference, pp 155 – 159, June 2010.

[9] Yaser Pourmohammadi Fallah, Darrell

Koskinen, Avideh Shahabi, Faizal Karim, Panos

 Nasiopoulos, “A Cross Layer Optimization 

Mechanism to Improve H.264 Video

Transmission over WLANs,” IEEE Consumer

Communications and Networking Conference(CCNC), pp. 875-8, 2007

[10] J. G. Apostolopoulos, “Reliable Video

Communication over Lose Packet Networks

using Multiple State Encoding and Path

Diversity,” Visual Communication and Image

Processing Conference, pp. 392-409, 2001.

[11] A. Reibman, H. Jafarkhani, Y. Wang, M.

Orchard, and R. Puri, “Multiple description

Page 7: Gl 2311161122

7/31/2019 Gl 2311161122

http://slidepdf.com/reader/full/gl-2311161122 7/7

Harsharndeep Singh, Meenu Dhiman, Pankaj Kumar Sehgal / International Journal of Engineering Research and Applications (IJERA)

ISSN: 2248-9622 www.ijera.com Vol. 2, Issue 3, May-Jun 2012, pp.1116-1122 

1122 | P a g e

coding for video using motion compensated

prediction," IEEE Inter. Conf. Image Processing

, October 1999.

[12] Mao, S., Lin, S., Panwar, S., Wang, Y., Celebi,

E., “Video transport over ad hoc networks:

multistream coding with multipath transport,”IEEE J. Sel. Areas Commun. Vol. 21, Issue no.

10, pp. 1721 – 1737, 2003.

[13] M. Tesanovic , D. R. Bull and A. Doufexi ,

“Enhanced Error -Resilient Video Transport over

MIMO Systems using Multiple Descriptions,”

IEEE Vehicular Technology Conference, pp. 1-

5, 2006.

[14] Larsson E. G. and Stoica P. “Space-time block 

coding for wireless communications”,

Cambridge University Press, 2003.

[15] Alamouti S. M. “A Simple Transmit Diversity

Technique for Wireless Communications”,

IEEE Journal on selected areas inCommunications, Vol. 16, Issue no. 8, pp.

1451-1458, October 1998.

[16] S. Lin, A. Stefanov, and Y. Wang, “On the

Performance of Space – Time Block-Coded

MIMO Video Communications,” IEEE

Transactions on Vehicular Technology, Vol.

56, Issue no. 3, pp. 1223-1229, 2007

[17] Kim, J., Hong, J.C., “Channel-adaptive

multiple description coding for wireless video

streaming,” 16thInternational Conference on

Computer Communications and Networks, pp.

474 – 478, 2007.

[18] A. Reibman, H. Jafarkhani, Y. Wang, and M.

Orchard, “Multiple description video codingusing rate distortion splitting,” International

Conference on Image Processing, pp. 978 – 

981, 2001.

[19] ITU-T and ISO/IEC JTC1, “Advanced video

coding for generic audiovisual services,” ITU-

T Recommendation H.264-ISO/IEC 14496-10

AVC, 2003.

[20] Karlsson, J., Li, H., Eriksson, J., “Real-time

video over wireless ad-hoc networks,” 14th

International Conference on Computer

Communications and Networks, pp. 596,

2005.

[21] Mahesh K. Marina and Samir R. Das., “Ad

hoc on-demand multipath distance vector

routing,” Computer Science Department,

Stony Brook University, April 2003.

[22] Sung-Ju Lee and Mario Gerla, “Split multipath

routing with maximally disjoint paths in adhoc networks,” ICC 2002, Helsinki, Finland,

June 2001.

[23] Xu, T., Cai, Y., “Streaming in MANET:

Proactive link protection and receiver-oriented

adaptation,” IEEE International Performance,

Computing, and Communications Conference,

pp. 178 – 185, 2007.

[24] A. Nasipuri, R. Castañeda, and S. R. Das,

“Performance of multipath routing for on-

demond protocols in mobile ad hoc networks,”

Mobile Networks and Applications, Vol. 6,

Issue no. 4, pp. 339 – 349, 2001.

[25] Gharavi, H., “Multi-channel for multihopcommunication links,” International

Conference on Telecommunications, pp. 1 – 6,

2008.

[26] J. Li, Z. J. Haas, M. Sheng, and C. Y. Chen,

“Performance evaluation of modified IEEE

802.11 MAC for multi-channel multi-hop ad

hoc network,” 17thInt. Conf. Adv. Inf. Netw.

Applicat., pp. 312 – 317, Mar 2003.

[27] W.C. Hung, K. L. E. Law, and A. Leon-

Garcia, “A dynamic multi-channel MAC for

ad-hoc LAN,” 21st Biennial Symp. Commun.,

Kingston, Canada, pp. 31 – 35, Jun. 2002.

[28] Monica A. Igartua, Victor .C. Frias, “Self -

configured multipath routing using pathlifetime for video streaming services over Ad

Hoc networks,” Computer Communications ,

pp. 1-32, 2010.

[29] S.J. Lee and M. Gerla, “Split multipath routing

with maximally disjoint paths in ad hoc

networks,” IEEE ICC, Helsinki, Finland, pp.

3201 – 3205, June 2001.