Enrich multi-channel P2P VoD streaming based on dynamic replication strategy

International Journal of Advances in Applied Sciences (IJAAS)
Vol. 9, No. 2, June 2020, pp. 110~116
ISSN: 2252-8814, DOI: 10.11591/ijaas.v9.i2.pp110-116  110
Journal homepage: http://ijaas.iaescore.com
Enrich multi-channel P2P VoD streaming based on dynamic
replication strategy
K.T. Meena Abarna, T. Suresh
Department of Computer Science and Engineering, Annamalai University, India
Article Info ABSTRACT
Article history:
Received Jun 27, 2019
Revised Feb 11, 2020
Accepted Mar 21, 2020
Peer-to-Peer Video-on-Demand (VoD) is a favorable solution which
compromises thousands of videos to millions of users with
completeinteractive video watching stream. Most of the profitable P2P
streaming groupsPPLive, PPStream and UUSee have announced a multi-
channel P2P VoD system that approvals user to view extra one channel at
a time. The present multiple channel P2P VoD system resonant a video at
a low streaming rate due to the channel resource inequity and channel churn.
In order to growth the streaming capacity, this paper highlights completely
different effective helpers created resource balancing scheme that actively
recognizes the supply-and-demand inequity in multiple channels. Moreover,
peers in an extra channel help its unused bandwidth resources to peers in
a shortage channel that minimizes the server bandwidth consumption. To
provide a desired replication ratio for optimal caching, it develops a dynamic
replication strategy that optimally tunes the number of replicas based on
dynamic popularity in a distributed and dynamic routine. This work
accurately forecasts the varying popularity over time using Auto-Regressive
Integrated Moving Average (ARIMA) model, an effective time-series
forecasting technique that supports dynamic environment. Experimental
assessment displays that the offered dynamic replication strategy which
should achieves high streaming capacity under reduced server workload
when associated to existing replication algorithms.
Keywords:
Active prediction of dynamic
popularity
Dynamic replication strategy
multi-channel system
P2P
This is an open access article under the CC BY-SA license.
Corresponding Author:
K.T. Meena Abarna,
Department of Computer Science and Engineering,
Annamalai University,
Annamalai Nagar, Chidambaram, Tamil nadu, India.
Email: abarnakt@yahoo.com
1. INTRODUCTION
Problem assertion
P2P VoD streaming system is totally different from the traditional P2P sharing networks in various
aspects. In P2P VoD system, each video is divided into small chunks those have a critical time constraints.
Therefore, it leads a major challenging task to design a chunk scheduling policy for effectively delivering
the requested video within its playback deadline. In present multi-channel live P2P video systems, there are
numerous performance problems including long playback, long channel switching delay and poor
performance for the fewer standard channels.[1] These performance problems are mainly caused due to
the two inherent characteristics such as channel dynamic churn and channel resource imbalance. This paper
mainly focuses on how to address the constraint by designing effective and optimal replication strategies to
improve the streaming capacity with less server bandwidth consumption. First, optimal replication policy is
still remains as an open problem so far how to replicate the videos proportional to its popularity. However, It

Int J Adv Appl Sci ISSN: 2252-8814 
Enrich multi-channel P2P VoD streaming based on dynamic replication strategy (K.T. Meena Abarna)
111
results in poor performance especially for unpopular channels and also inaccurate to predict the different
viewing popularity over time. Therefore, the main scope of this paper is to propose a time-series analysis
techniques to predict the popularity accurately in P2P-VoD systems. It achieves an effective replication
policy replicate enough replicas based on dynamic popularity, and deficit bandwidth of unpopular movies
will contribute the server workload that improves the streaming capacity with reduced server workload.
The main aim and objectives of the paper
- To utilize the cross channel peer upload bandwidth for improving the streaming capacity in a multi-
channel P2P VoD systems.
- To propose an everyday and active replication algorithms in a spread and active fashion.
- To replicate the videos proportional to the dynamic popularity so as to reduce the server workload.
- To propose the peer scheduling policy for effectively deliver the requested video with less intra-domain
traffic in a smart and cooperative way.
The main contribution of this paper is
- Active Prediction of Dynamic Popularity: This work accurately predicts the dynamic popularity over
time using standard linear predictor model called as autoregressive integrated moving average model
ARIMA(x, y, z). This model deploys an effective time-series forecasting technique to predict the
popularity even under dynamic environment.
- Dynamic Replication based on Optimal Tuning: This work proposes an effective dynamic replication
that replicates the video proportionally based on dynamic popularity in a distributed and dynamic
manner. In order to optimize the replication in a high dynamic P2P VoD system, this approach proposes
two types of tuning such as Proactive and Reactive tuning methods to achieve the desired
replication ratio.
2. RESEARCH METHOD
The main purpose of this work is to recover the streaming size of a multi-channel P2P video system
by irresistible its two fundamental characteristics: channel churn and channel resource imbalance.While
regarding the multi-channel systems [2], Wu et. al [3] proposes two strictly linked papers to recover
the server bandwidth utilization in multi-channel P2P streaming systems. In [3], Wu et al. proposed, an
online server capacity provisioning algorithm to alter the supply of server bandwidth proactively between
the dissimilar channels rendering to the expected demand, the streaming quality, and the priorities of
channels. In [4], Wu et al.proposed the effective optimization algorithm to reduce the main two problems
such as dynamic channel churn and channel resource imbalance between multiple channels. Hence, this
method permits active cross channel resource distribution and also achieves reliability in multi-channel P2P
streaming systems.
In order to analyze the server bandwidth consumption among the peers with either homogeneous or
heterogeneous upload capacity, three models [5-7] are built in multi-channel VoD systems. Kumar et al. [5]
develop a simple stochastic fluid model that seeks to expose the performance limitations of channel based
P2P streaming systems. This model provides closed-form expressions to examine the fundamental
characteristics of a P2P streaming system, including the dynamic churn, heterogeneous upload capacity,
limited infrastructure capacity and peer buffering and playback delay. However, this study assumed that
channels are of homogeneous playback rates. Moreover in [1], the same authors further extended a tractable
infinite server queuing network model to capture heterogeneous peer channel switching patterns. This paper
analytically studies the performance of multi-channel systems by considering peer channel switching, peer
churn, bandwidth heterogeneity and zipf-like channel popularity. In [2], Linear programming model differs
from the aforementioned two models because it is independent of implementations. This approach provides
a closed form solutions due to its linear property that paves a way to explore the design space of multi-
channel systems numerically. In [8], the linear programming model used to analyze the three bandwidth
allocation schemes such as Naive Bandwidth allocation Approach (NBA), Passive Channel-aware bandwidth
allocation Approach (PCA) and Active Channel-aware bandwidth allocation Approach (ACA). They are
analyzed in terms of streaming quality, channel structure, implementation complexity, peer population
distributions and upload bandwidth distributions using bandwidth satisfaction ratio. Compared to NBA and
PCA designs, ACA design provides effective performance since it allows a peer to subscribe to unwatched
channels. However, this approach does not compare the system performance under peer dynamics (channel
switching/peer leaving) in the transition state. Still, none of these proposals has taken collaboration of normal
peers in multiple VoD channels into consideration.

 ISSN: 2252-8814
Int J Adv Appl Sci, Vol. 9, No. 2, June 2020: 110 – 116
112
2.1. System model
In this work, we consider a system model of multi-channel P2P-VoD system[1] G represent as
{S, P, V} where S is the streaming server of the system, P is a set of peers {p1, p2 …pN} and V is a set of
videos represent as {v1, v2… vk}. Peers in the system include both set of active peers {ps1, ps2… psh} and set
of inactive peers {prep1 prep2… prepk}. The proposed system encompasses m number of channels {ch1, ch2…
chm} where each channel consist of set of client peers connected by mesh based P2P links {l1, l2… lR}.
The streaming capacity for a channel rchmdefined as the maximum streaming rate or video quality that can be
obtained by each peer in the channel chm. The server upload bandwidth allocated to the set of channels
represented as {sch1, sch2… schm}. Let UN is the maximum upload capacity of peer (pN). In this P2P assisted
peer scheduling policy, a peer wants to view a video vk can access the data from three components such as i)
streaming server ii) synchronized (active) peers denotes as {ps1, ps2… psh} which are currently watching
the video (vk) and iii) replication (inactive) peers denotes as {prep1 prep2… prepk} which are not currently
viewing the video but cached in its local cache space. Each peer downloads the video with a playback rate
(pr) to achieve less start-up latency and reliable streaming quality. Each peer independently maintains
the local cache to store the cached videos. When a peer enters or leaves the system, video replica is cached or
gets ejected; the peer must send heart beat messages to the tracker in order to indicate its active presence in
the channel. Therefore, tracker maintains both the peer statistics and cached information about the peers in
the network. This proposed approach undergoes two processes such as i) Synchronous uploading:
synchronous peer who entered earlier than requesting peer (Preq) can able to provide the requested video for
Preq. ii) Greedy scheduling: maximum cooperation between the synchronous peers to maximize the number of
peers to download data at the required playback rate with high streaming quality.
2.2. Dynamic replication based on optimal tuning
This work proposes an effective dynamic replication [9] that replicates the video proportionally
based on deficit bandwidth in a distributed and dynamic manner. Therefore, it minimizes the upload
bandwidth consumption of server S that reduces the server workload due to the caching of enough replicas
among the peers in multi-channel P2P VoD systems. It provides a low start up latency for accessing
the videos and supports a required playback rate to improve the streaming capacity. In order to optimize
the replication effectively in a high dynamic P2P VoD system [1], this approach proposes two types of tuning
such as Proactive and Reactive tuning methods tune the number of replicas to achieve desired replication
ratio [10].
2.2.1. Reactive tuning
When the cache of peer is full, then effective cache replacement algorithm tunes the replication ratio
according to the deficit bandwidth (Udef) in order to reduce the server workload. Peer has to decide the video
to be removed from the local cache to provide space for newly arrived data. In that case, peer replaces
the cached data item based on its Enough Replica (ER) index that computes from the deficit bandwidth.
Cache replacement algorithm is illustrated as follows.
// N is number of replicas
peer p1 in channel ch2 watch video v
if cache(i) contains video v
then no cache replacement
else
do replace {
computer the number of replicas in cache (cachedcur
) for video v;
computer the number of replicas to be expected (cachedexp) to be cache
for (i=1, i<N; i++) {
cachedpre
=(Ui*i)/Udef
}
compute ER of each replica in local cache;
𝐸𝑅 =
𝑐𝑎𝑐ℎ𝑒𝑑 𝑐𝑢𝑟
𝑐𝑎𝑐ℎ𝑒𝑑 𝑝𝑟𝑒
}
This replacement approach computes the enough replica index to determine that whether replica of
the video is enough to meet the future request. The ER index is the ratio of the number of current cached data
items (cachedcur
) and the number of expected data to be cached (cachedpre
).
𝐸𝑅 =
𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑐𝑢𝑟𝑟𝑒𝑛𝑡 𝑐𝑎𝑐ℎ𝑒𝑑 𝑑𝑎𝑡𝑎 𝑖𝑡𝑒𝑚𝑠(𝑐𝑎𝑐ℎ𝑒𝑑 𝑐𝑢𝑟)
𝑁𝑢𝑚𝑏𝑒𝑟 𝑝𝑟𝑒𝑑𝑖𝑐𝑡𝑒𝑑 𝑑𝑎𝑡𝑎 𝑖𝑡𝑒𝑚𝑠 𝑡𝑜 𝑏𝑒 𝑐𝑎𝑐ℎ𝑒𝑑 (𝑐𝑎𝑐ℎ𝑒𝑑 𝑝𝑟𝑒)
(1)

113
If the computed ER index is less than one (ER<1), the number of available replicas is not enough to
meet the required replication ratio. On the contrary, computed ER index is greater than one (ER>1),
the number of replicas is much enough to meet the desired replication ratio. Therefore, cached replicas which
has high ER index remove out from the cache in order to evict the unwanted replicas when the cache is full.
Therefore, enough replica index based cache replacement techniques reduces the server load and also
achieves the optimal desired replication ratio.
2.2.2. Proactive tuning
Cache replacement algorithm reduces the server workload only in the case when the popularity of
the video is uniform all over the time. However, the popularity of a video may varies dynamically (non-
stationary), therefore, server workload increases when there is surge demand for video. It degrades
the system performance and takes longer time to obtain the desired replication ratio. Therefore, this work
proposes a proactive approach that predicts the popularity using standard linear predictor model called as
autoregressive integrated moving average model ARIMA (x, y, z) [9]. This model deploys an effective time-
series forecasting technique to predict the popularity even under dynamic environment. In order to predict
the popularity, this approach differentiates the non-stationary time series (NSt)into y times for deriving
the stationary time series St. The stationary time series St is the linear weighted sum of x values in the series
{St-1, St-2… St-x} and z number of casual errors {Et-1… Et-z} This approach deploys two phases such as
regression model recognition and regression model evaluation to predict the popularity of the data item
linearly. Regression model recognition identifies the appropriate values for x, y, z. And then, in
the regression model evaluation estimates the coefficients for the linear weighted summation that is x+z;
Thus, the popularity prediction for time t+1 computes ARIMA (0, 3, 2) as follows
(2)
Here,  is the co-efficient for the casual error (Etand then casual error at a future time Et+1 is zero and then
(3)
Substitute Et in equation
(4)
In order to derive the coefficient, this approach dynamically refines the ARIMA model by training
the model using popularity statistics of the most recent n times in a dynamic fashion and then value of
the coefficient of casual error  is derived. The popularity of the data is accurately predicted using (2).
Dynamic Popularity based Push algorithm are explained as follows
Step 1: Peer statistics Collection
Number of active peers in ech channel
Step 2: Popularity Statistics Collecton
Statistic: collect the most recent n times popularitu statistics
Step 3: Supervise learning the model
Train ARIMA (0,3,2) using collected popularity statistics
Step 4: Popularity Prediction
Predict the video popularity for time t+1 at time t
(t 1) 13 2 (P Pt)t t tP P P   
Step 5: Checking of confidence interval for predicted popularity
if ( (t 1)P  lies with in confifence interval of 1tP
)
Correct Popularity Prediction:
else
retrain the ARIMA (0,3,2) using collected popularity statistics.
Step 6: Push approach to tune replica
if(P(v)>Threshold)
Replicate the video v to meet desired replication ratio
else
push out the video v;

 ISSN: 2252-8814
114
In this Active tuning, each peer actively replicates the number of replicas of data items, which have
predicted high popularity in the future. On the other hand, less popular data items with predicted low
popularity are pushed out when its number of replications is greater than the desired replication ratio. In this
proactive tuning approach, each peer proactively predicts the popularity of the data item in its local cache
during idle time. Then, each peer replicates the data item based on its predicted popularity in order to meet
the desired replication ratios. It reduces the server workload at the same time improves the streaming quality
3. RESULTS AND ANALYSIS
This section carry out an extensive simulation to validate and evaluate the performance of proposed
dynamic replication strategy with helpers based resource channel allocation approach. Experimental set up
comprises a nearly 5,000 peers and streaming server provide nearly 200 videos with an upload capacity of
70Mbps. Each video plays at a playback rate (Pr) of 500Kbps and its popularity follows Zipf distribution.
The size of the video is 60 minutes, which is consistently divided into 60 segments. The peer’s upload and
download sizes uniformly spread among in the range of 1.5 Mbps and 3.0 Mbps. Each peer preserves a buffer
with a capacity of 5 sections. The playback time of each peer is dispersed randomly between 0 and 60
minutes. Moreover, experimental results show the helpfulness of the proposed approach in terms of
streaming capacity and reduction of server load by comparing with the existing proportional
replication approach.
3.1. Average streaming capacity
Figure 1 shows that the proposed dynamic replication approach achieves high streaming capacity
than the existing proportional approach in accordance to the increasing server upload capacity. In proposed
approach, the streaming capacity increases gradually by optimally allocating the server upload capacity
among the multiple channels using helpers based resource sharing scheme. Whereas in the existing scheme,
peer bandwidth resources shares within the same channel, not among the multiple channels. Therefore,
expected streaming quality cannot be acquired in proportional replication approach.
Figure 1. Average streaming capacity in dynamic replication
3.2. Reduction of server load
3.2.1. Effect of cache size
Figure 2 shows the reduction of server load in a proposed dynamic replication approach. According
to the increasing cache size, active peers itself can able to satisfy the request from any other peers in
the system. Therefore, requested peer does not depend upon the server for streaming. Thus, the server
workload can be predominantly reduced according to the increasing cache size. The following graph clearly
examines that when the cache size is small, both the approaches come under the same server workload.
In Dynamic Replication, peers replicate videos in a smart and cooperative way to avoid repeatedly caching of
videos that are likely to be cached by the other peers in the system. More importantly, when the cache is large
enough, proposed dynamic replication performs better than the existing proportional replication approach.
10 20 30 40 50 60 70
0
0.5
1
1.5
2
Server Upload Capacity (Mbps)
StreamingCapacity(Mbps)
Average Streaming capacity of Dynamic Replication
Dynamic
Proportional

115
Figure 2. Reduction of server load in dynamic replication
3.2.2. Effect of the number of peers
Figure 3 shows that the dynamic replication approach acquires less server workload than the already
existing proportional replication approach even under a large number of peers. This is because; proposed
approach signifies the effective replication of the number of replicas in a distributed and dynamic manner
that makes a better use of the peers’ cache space. Therefore, effective maintaining of the videos in a cache
space improves the streaming quality and also reduces the server workload.
Figure 3. Reduction of server load in dynamic replication
4. CONCLUSION
This paper mostly reflects the recently emerging multi-channel P2P video-on-demand streaming
service and the problem of how to use collaboratively. In order to optimize the replication, this paper
proposed two types of tuning such as passive and active tuning to achieve desired replication ratio
Furthermore, presented a mathematical framework to optimize the replication based on dynamic popularity.
The proposed algorithms are effective evenunder a dynamic churn and videos with different viewing
popularity. It uses an effective time series forecasting technique, autoregressive integrated moving average
model ARIMA (x, y, z) to predict the popularity over time. Experimental evaluation illustrates that proposed
approach achieves high streaming capacity and less server workload than existing replication approaches.
1 1.5 2 2.5 3 3.5 4
0
1
2
3
4
Cache size (MB)
Serverworkload*10
5
Reduction of server workload in Dynamic Replication
Dynamic
Proportional
1000 2000 3000 4000 5000
0
1
2
3
4
Reduction of server load in Dynamic Replication
Number of peers
ServerLoad*(10
4
)
Dynamic
Proportional

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116
REFERENCES
[1] Z. Wang, C. Wu, L. Sun, and S. Yang, “Strategies of collaboration in multi-channel P2P VoD streaming,” IEEE
Global Telecommunications Conference, pp. 1-5, 2010.
[2] Yifeng He and Ling Guan, “Improving streaming capacity in multi-channel P2P VoD systems via intra-channel and
cross-channel resource allocation,” International Journal of Digital Multimedia Broadcasting, vol. 2012, 2012.
[3] C. Wu, B. Li, and S. Zhao, “Multi-channel live P2P streaming: Refocusing on servers,” Proceedings of the IEEE
international conference on Computer Communications, 2008.
[4] D. Wu, C. Liang, Y. Liu, and K. Ross, “View-upload decoupling: A redesign of multi-channel P2P video systems,”
Proceedings of the IEEE 28th Conference on Computer Communications, pp. 2726–2730, Apr 2009.
[5] R. Kumar, Y. Liu, and K. Ross, “Stochastic fluid theory for P2P streaming systems,” Proceedings of the 26th
IEEE
International conference on Computer Communications, pp. 919–927, 2007.
[6] D. Wu, et al., “Queuing network models for multichannel P2P live streaming systems,” Proceedings of the IEEE
International conference on Computer Communications, pp. 73–81, 2009.
[7] M. Wang, L. Xu, and B. Ramamurthy, “Linear programming models for multi-channel P2P streaming systems,”
Proceedings of the IEEE INFOCOM, pp. 1–5, 2010.
[8] Miao Wang, et al., “Exploring the design space of multichannel peer-to-peer live video streaming systems”,
IEEE/ACM Transactions on Networking, vol. 21, no. 1, pp. 162-175, 2013.
[9] Y. Zhou, T.Z.J. Fu, et al., “A unifying model and analysis of P2P VoD replication and scheduling”, Proceedings of
the IEEE INFOCOM, pp. 1530 – 1538, 2012.
[10] W. Wu and J. Lui, “Exploring the optimal replication strategy in P2P VoD systems: characterization and
evaluation”, In Proceedings of the 30th IEEE International Conference on Computer Communications,
pp. 1206–1214, 2011.

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