These conflicting results can be attributed to several variables including the contexts where the studies have been conducted e.g. ESL or EFL, the research methodologies adapted by the researchers especially peerscaffolding training, the length of the investigations, and the pair/group structures, as well as the age, gender, English proficiency level, and personal and socio-cultural characteristics of the participants. Hence the wide range of variables that can largely affect the findings of pair/small-group peerscaffolding research in general, and problems such as novice L2 learners‟ inability to identify their classmates‟ errors, their doubtful feeling about the accuracy of their classmates‟ comments, and their reluctance to use their peers‟ suggestions when placed in pair or small-groups which have been reported by several researchers as impeding factors in successful integration of pair and small-group peerscaffolding in L2 writing courses in particular, provide incentive for further research to clarify the role and potential learning benefits of collective peerscaffolding in EFL writing contexts. As it was stated earlier, collective peerscaffolding refers to those activities in which all students of the class work together and pool their writing knowledge and resources to provide assistance (scaffold) to the representative paragraphs written by their classmates in an attempt to improve their quality in subsequent drafts. Furthermore, although previous studies have explored pair/small-group scaffolding, little attention has been paid to a large group of learners (whole class) performing such task. It is hoped that engaging the whole class in peerscaffolding/collaboration activities alleviate some of the concerns expressed by L2 researchers and practitioners working with pairs or small groups. Therefore, drawing on „collective scaffolding‟ tenet (Donato, 1994), the present study aimed to address these issues by seeking volunteered learners‟ perceptions of participating in this activity. To serve that end, the following research question was formulated:
The data for the present study are part of a larger research project in English on Dynamic assessment in EFL process writing. Twenty-four Persian native speakers who were studying English were included in the project to examine the effects of symmetrical and asymmetrical scaffolding behaviors on their writing ability. They were homogenized based on their scores obtained from a TOEFL test and all of them had passed paragraph writing as a compulsory course at the same university and were randomly assigned to two groups of 12. Different stages of process writing framework proposed by Seow (2002) - brainstorming, spidergram, outlining, drafting, revising, and editing- were explained to the participants of both groups. In one class pairs of 2 were formed randomly and the class was provided with teacher and peerscaffolding, while the other class was provided with non-dynamic instruction. The treatment lasted for 16 sessions. This study consisted of both quantitative and qualitative parts. Data were obtained from learners’ writings on the given topics before and following the treatment. Both peer and teacher- learner interactions were audio recorded and transcribed. Scores obtained from pretest and posttest were the main sources of quantitative data while transcriptions of the recorded interactions and results of interviews were examined qualitatively.
According to Wood et al. (1976), for scaffolding to be effective, learners have to: a) recruit the tutee’s attention, (b) reduce degrees of freedom in the task in order to make it manageable, (c) keep direction in terms of the goals, (d) mark critical features, (e) control frustration, and (f) model solutions, while in the observed behavior of the learners they could only recruit the tutee's attention. This is different from the teacher scaffolding session in which the teacher through the devices of elaboration, explanation, and questions tried to keep learners' attention, direct them, model solution, make understanding of the talk critical, and give a model for the solution by pointing to some notes and providing comments on learners' output. In the class scaffolding and peerscaffolding sessions that the environment tended to be guided by tension, the learners used examples in their "I think" utterances. The point here is that learners may not know exactly how to proceed in the process of scaffolding. The teacher, who was well familiar with SCT and its pedagogical implications, could benefit from the scaffolding techniques and means appropriately, but this does not mean that students can take such a role. Learners need to be taught how to scaffold. In the Iranian educational system in which the dominant mode of teaching is teacher centered through the monologue, the scaffolding techniques of social constructivism approach might not be effective when learners take the control. Maftoon and Nasser (2009) maintain that learners need time and practice for scaffolding. They have to be taught explicitly how and when to scaffold.
Xie, (2006) hypothesized that by interacting with peers through online collaboration; students will perform better in problem solving. Problem solving can be viewed as a learning outcome and as a process (Mayer & Wittrock, 1996). Park and Jang (2008) have presented four phases of a problem solving process. The four phases are understanding, planning, solving, and checking. Hence, these four phases of problem solving existed in order to find the pattern and types of peerscaffolding, and they are practiced during group problem solving activities.
In contrast to this claim Baleghizadeh, TimchehMemar, and TimchehMemar (2010) by doing an experiment dare to say that because of some affective factors like the fear of failure, and anxiety, symmetrical group students who are homogeneous concerning knowledge are more successful than asymmetrical group students in reading comprehension. So, anxiety can have a debilitating effect on the reading comprehension of EFL students (Woodrow, 2006), and these authors suggest that dividing students into symmetrical groups in the class can decrease this affective factor. However, as Mattos (2000, as cited in Yu, 2004) explains sometimes peerscaffolding in group work may have a negative effect on the learners. Some negative affective factors (filters) may interfere with the learners' learning process and subsequently, they cannot cooperate well and this can debilitate students' adaptation and achievement to their educational goals and ultimately, those affective factors negatively affect their language learning process.
Educators and researchers have used the concept of scaffolding as a metaphor to describe and explain the role of adults or more knowledgeable peers in guiding learning and development (Nguyen, 2013; Verenikina, 2008; Krause, Bochner & Duchesne 2003; Hammond 2002; Daniels 2001; Stone 1998). Vygotsky (1978) through the concept of the Zone of Proximal Development (ZPD) in the Socio-constructivism theory posited that mediation is not limited to that of only teachers or adults, but peerscaffolding is also important for internalisation of knowledge, development of skills and learning progress. It was further explained that when a child is in interaction with people and in cooperation with his peers, learning a series of internal developmental processes occurs.. Fundamental communicative language skills such as listening and speaking would progress through social interaction.
can reject, accept or redirect the new peer’s request. The port portMML of the MM servent is used to leave the overlay network and it expects a single incoming message called leaveOverlayNetwork. A peer wishing to advertise its services sends an advertise message to the port portSA of its ServiceAdvertisement (SA) servent. The SA servent may advertise the service detail to the SA servent of the other peers on the overlay network and responds back to its peer with a success or fail message. The ServiceDiscovery (SD) servent is used to discover the details of services on the overlay network that match a search criterion. The portSD port of the SD servent expects a single incoming message ﬁndService with the search criteria and responds with the details of a list of services matching the search criteria. The Naming (N) servent is used to assign a unique identiﬁer to entities in a P2P system (using portGetID) and to resolve an entity’s id to a physical IP address (using portGetPeer).
A overlay network can be classified into three types, 1. decentralized, 2. partially decentralized, and 3. centralized networks, based on the degree of centralization. The decentralized overlay networks realize the purest form of P2P network. The functionality and the tasks that each peer performs are identical and there is no distinction between one peer from another. Each peer can issue, relay, and reply to query or service messages. In a partially decentralized P2P network architecture, some peers may have more important role than others, such as acting as a message relay hub or providing local index lookups for its neighboring peers. The partially decentralized overlay network is a natural adaptation of the fully decentralized overlay to the heterogeneous capabilities among different peers. Peers with higher storage space or CPU power are often elected as localized information hubs, and hence are given a more important role. A centralized overlay network suggests that there is a centralized server that provides the data lookup service for the entire network even though the end-to-end interactions and file exchanges are performed directly between two peers. Obviously, the centralized architecture violates the design concept of a P2P network, although this type of overlay network is still sometimes considered as P2P, e.g. BitTorrent. The centralize overlay network is vulnerable to single-point of failure and malicious attacks just like client-server model.
In the recent years Peer-to-Peer (P2P) technology gets the more attention from the research community as well as the industry. Decentralization is one of the main concepts of P2P networks that make it more attractive. The P2P system is a distributed system consists of a set of cooperative computers, known as peers, which share their resources like CPU cycles and memory with other peers in the system without any central authority. It is a virtual network built on top of a physical network. Initially P2P networks are used only for file sharing applications such as Napster  and BitTorrent. Nowadays P2P networks are also used for developing large scale distributed computing applications. The SETI@home  and distributed.net  are the well-known examples of such kind of systems. P2P computing is a form of distributed computing that can utilizes the idle CPU cycles of PCs connected on the Internet. The P2P computing systems are dynamic in nature, i.e. peers may join or leave the system at its own decision occasionally. According to the degree of decentralization the P2P systems are classified into two categories: hybrid systems and purely decentralized system . In hybrid P2P systems there is a central peer which maintains the information about all the member peers. This peer is also known as directory server or super peer. The SETI@home and distributed.net falls under this category. In pure P2P system there is no central point of control. All the peers have equal functionality in the system. Pure P2P systems are scalable in nature by avoiding need of centralized
removal of support as the learner becomes more autonomous and take on more responsibility for learning. The term is coined by Collins, Brown, and Newman (1989) and defined as ‘Once the learner has a grasp of the target skill, the master reduces (or fades) his participation, providing only limited hints, refinements, and feedback to the learner, who practices successively approximating smooth execution of the whole skill’(p. 456). Furthermore, fading is a gradual process accompanied by less frequent and less detailed strategies. With reference to this definition, Pea (2004) infers that fading is an indispensable feature of scaffolding without which this support develops distributed intelligence, a concept drastically different from scaffolding. He contrasts distributed intelligence with scaffold-with-fading and adds that this ‘intelligence is distributed across people, environments including designed artifacts, and situations’ (p. 431). In this respect, assistance such as availability of tools amplifies intelligence and unassisted performance is unnecessary. In other words, there is no scaffolding without fading.
Scaffolding is “the dialogic process by which one speaker assists another in performing a function that he or she cannot perform alone” (Ellis, 2003, p. 180). The term ‘scaffolding’ was firstly defined by Wood, Bruner, and Ross (1976). According to them, scaffolding is “adult controlling those elements of the task that are essentially beyond the learner's capacity, thus permitting him to concentrate upon and complete only those elements that are within his range of competence” (Wood, Bruner , & Ross, 1976, p. 90). As the concept of scaffolding parallels the theory proposed by Vygotsy. Scaffolding was adopted and used with Vygotsky’s work (Ellis, 2003). It is a kind of supportive dialogues (Aljaafreh & Lantolf, 1994) It is sometimes referred to as ‘assisted performance’ (Ohta, 2001).
Kademlia is a dispersed hash counter on behalf of a dispersed P2P computer systems intended by David Mazières and PetarMaymounkov in 2002. It states the assembly of the system and the interchange of statistics through the peer lookups. Kademliapeers converse among them by means of UDP. A simulated or overlap system is molded through the contributing peers. Every peer is recognized by a symbol or peer ID. The ID of the peer assists not merely as identification; however the Kademlia process utilizes the peer ID to trace standard. In fact, the peer ID offers a straight plot to file hashes and that peer accounts statistics on where to acquire the file or resource .
Kazaa is a peer to peer protocol that performs both searching and downloading via other nodes in the network. Where faster computers with higher bandwidth connections to the Internet are detected, these are promoted to a supernode. Supernodes contain information about the files that they are sharing, but also for other nodes nearby on the network. This attempts to increase search coverage while minimising connections between nodes and bandwidth.
The emerging P2P ecology allows us to open a critical perspective on the technological determinism and privileg- ing of technical innovation that now pervades contemporary neoliberal digital capitalism. Indeed, this ecological change within social and technological relations coincides with these contemporary modalities of production, seen in dominant and pervasive enterprise initiatives in every labour sector in the neoliberal era. Can the emergence of P2P participants’ battle with capital transform the traditional hierarchies that characterised sites of production typical of the industrial age? The contemporary post-capitalist ecology I have described here does seem to allow workers to arrest their own self-management. They return to a situation wherein people can formulate revolutionary subjectivities and own their labour and means of production, rather than continue to be subordinated to hierarchies and determin- istic views of technology and progress. The self-organising communities of peer production threaten the status quo by taking ownership of the means and modes of production. This also involves rethinking ecologies of production , beginning with the structuring of capital output into a commons from which to adopt and adapt, whether personally or communally, through the use of the General Public Licensing model which renders intellectual property obsolete.
Peer-to-peer routing has now been used for several years in a diverse range of applications. Despite the age of many such protocols, little work has gone into providing their for- malised models. Existing analysis typically consists of sim- ulated network scenarios rather than any proven mathemat- ical models. While this is not necessarily the case for older, unstructured algorithms, it is certainly true for newer, struc- tured protocols. As compared to simulations, models can allow for much quicker evaluation of protocols at a wide range of settings. Furthermore, they can sometimes help to gain an in-depth understanding of the protocols. Given the popularity of many such peer-to-peer systems, it is therefore important to provide their formalised models.
The simulation recorded every interaction, thus a list of true global contribution scores of each peer is available for the use of evaluation. After 300 rounds of bootstrapping interaction, one randomly choosed peer S started to discover the other 99 peers’ contribution scores by selective polling. We separate the results of selective polling into two sets, G1 and G2. G1 is the set of peers who have at least one interest file category the same with S. Peers in G1 are highly possible to interact with S. G2 is the set of peers who do not have any interest overlapped with S. They are unlikely to interact with S.
Along with the increased performance by introducing in- centives comes an increased reliability. When there is a reason to share files, users become predictable, and thus it is not pure chance anymore whether a given file is avail- able in the network. This predictability of the peers makes it possible to use peer-to-peer architectures in non peer-to- peer areas which have a peer structure but are dominated by either centralized approaches or by the requirement of a cooperative environment, specifically Grid networks and mobile ad-hoc networks.