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Pipeline Data Compression and Encryption Techniques in E- Learning environment

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Journal of Theoretical and Applied Information Technology © 2005 JATIT. All rights reserved. www.jatit.org Pipeline Data Compression and Encryption Techniques in ELearning environment. A.V.N.Krishna1, Dr. A.Vinaya Babu2 1Associate Professor, CSE Dept. Indur Institute Of Engg. & Tech. Siddipet, Medak Dist. Andhra Pradesh. , 2Director, School for Continues and Distance Education, J.N.T.U. Hyderabad. ABSTRACT. One of the recent developments in telecommunication industry is the introduction of communications through Internet. Some of the applications of internet are easy communications, vast library of information at one place, electronic business through internet, e learning modules and so on. Elearning is an important application of communication through Internet. E Learning is an integrated and continues approach to build knowledge skills and competencies through web enabled technologies. Effective e learning is having advantage in delivering the right content to the right person at the right time. E learning uses the new or existing network connections connected to internet. The wide area network maintains a high speed connection to an internet service provider that local centers can use to connect to the central LAN from a geographical distance away. Though they offer great accessibility, every one using the internet can see the traffic that passes between a local center and central office over these insecure internet LAN connections. Considering the fact that different encryption approaches target different types of computational complexity, it may be interesting to see if any further improvement can be achieved when different data encryptions are arranged with compression into a pipeline operation. In this work some effort has been put to calculate computational complexities and computational overhead of some encryption algorithms in e- learning environment. Key words: Compression Algorithm, RSA Encryption, Arithmetic coding algorithm, Comparative study, A new algorithm. Introduction complexity and overall improvement in e learning technologies. When ever a network connection leaves a building, The idea of an encryption system is to security to data is a must. Virtual protocol network disguise confidential information in such a way security is most widely used technique for this that its meaning is unintelligible to an purpose. This technique uses relatively low cost, unauthorized person. The information to be widely available access to public networks like the concealed is called plain text and the operation of internet to connect remote sites together safely. To disguising it is called enciphering. The enciphered obtain security objectives cryptographic message is called cipher text or cryptogram. The techniques are used to block outside traffic from person who enciphers the message is known as mingling with shared internal network. encipherer where the person to whom he sends the Different architectures can be used for virtual cryptogram is called the receiver. The set of rules networks like 1. Software 2. Look aside (S/W & which the encipherer uses to encipher his plain text H/W) 3. Flow through (H/W). All these is called algorithm. techniques involve the steps like 1. Encryption Much of this work concentrates on different algorithms 2. Packet parsing and classification 3. security algorithms and their relative advantages Process packets 4. Compression, encryption & and limitations. The different algorithms discussed authentication. Crypto processing will require a lot in this work are substitution cipher, public key of resources and many hosts will reap significant algorithm and a new algorithm. performance benefits if processing load is reduced. In this context different encryption algorithms will Encryption techniques. be discussed in terms of their computational overhead, confidentiality &authentication. The 1. Substitution Techniques. A Substitution study provides some insight into overall technique is one in which the letters of plain improvement in data transmission, better band text are replaced by other letters or numbers or width utilization, reduction in computational symbols. If the sequence is viewed as a 37 Journal of Theoretical and Applied Information Technology © 2005 JATIT. All rights reserved. www.jatit.org sequence of bits, then substitution involves replacing plain text bit patterns with cipher text bit patterns. If we assign a numerical equivalent to (3) each letter then the algorithm can be expressed as follows. For the plain text letter P, substitution Therefore, if we choose the pair (e, n) as an cipher text C, encryption key, and (d, n) a decryption key, we C = E(P) = (P+3)mod(26) will obtain the cyphertext for any integer M A shift may be of any amount, so that general ceaser algorithm is as: C = E(P) = (P+K) mod(26) Where K takes on a value in the range 1-25. The decryption algorithm is simply (4) P=D(C) =( C-K)mod(26) For decryption, we have: If it is known that a given cipher text is a ceaser cipher , then a brute force cryptoanalysis can be easily performed. Simply we have to try all possible 25 keys. If the cryptoanalyst knows the nature of plain text , then the analyst can exploit (5) the regularities of the language. For example From equations (1) and (3), it becomes: Plain text: To fill Key { m,p,g,s,d,t,u,w,b,z,k,n,o,c,q,y,e,u,f,I,k,j,h,j,r,l} Cipher text iqtbnn. (6) 2. RSA Encryption RSA algorithm is established on the basis of: (1) where n is a product of two large prime numbers P and Q. M is any integer which satisfies and is the Euler totient function which is set to be: , and relatively prime to n. According to the properties of totient functions, we have: (2) To obtain the encryption key, a random integer, d, is selected to be greater than both P and Q. The integer, d, is also relatively prime to , namely gcd(d, )=1 (gcd=greatest common divisor). After that, another integer, e, can be computed by the following equation: When the input message is represented by a series of integers, which are less than n (message = M), we can get the encrypted message correctly decrypted. Regarding the security of this encrypted message, as long as the prime numbers P and Q are selected large enough, it will be very difficult to find out the two numbers only from n by any existing factoring algorithm. In the operating procedure, the encryption key (e, n) is normally made public, but the decryption key (d, n) is always kept private. Whenever a message is encrypted by anyone in public, only the person with the decryption key can get the right message. The encryption algorithm can also be used in the public-key cryptosystem. Assuming person A needs to send a signed cheque to person B, he can use his private key dA to sign the cheque (message M). The signed file becomes S=dA(M). For the purpose of privacy, he can use person B’s public encryption key eB to encrypt S, and send the encrypted file eB(S) to person B. Person B can use his private key dB to get S. Knowing that the cheque is signed by person A, he then use person A’s public encryption key eA to decrypt S, and finally get the decrypted cheque. 2. A New Encryption Algorithm 38 Journal of Theoretical and Applied Information Technology © 2005 JATIT. All rights reserved. www.jatit.org 3. Generate a “ternary vector” for 23 values i.e The new algorithm has the following features from 0 to 8 1. A set of mono alphabetic substitution rule 4. Let this be “B”. 5. Multiply A * B| ; is used. 6. Consider remainder of the multiple with 3. 2. A matrix is used which is used as a key. 7 A sequence is generated. 3. The matrix key generates a sequence. 8. This sequence used as key. 4. This sequence is used to the character in 9. Each numerical value of the plain text is added the plain text by a particular chosen rule. to the key to generate cipher text. 10. The algorithm is reversed to get plain text from The new algorithm is combination of cipher text. a. Substitution cipher b. Matrix key which generates sequential pattern. c. Modified Ceaser algorithm. d. Coding method. The steps that are involved in the proposed algorithm. 1. The letters of alphabet were given numerical values starting from 0 2. A random matrix used as a key. Let it be A. It can be seen that to extract the original information from the coded text is highly impossible for the third person who is not aware of encryption keys and the method of coding. Even if the algorithm is known it is very difficult to break the code and generate key, given the strength of the algorithm .Thus given a short response time through internet communication ,the algorithm is supposed to be safe. Example: n=0 to 7 n1=floor(n/2);r1=n-n1*2; n2=floor(n1/2);r2=n1-n2*2; n2=r3; r=[r3 r2 r1]; r=r’= | r3 | | r2 | | r1 | |__ ___| __ __ A=key= | 4 | 2 4 -5 | | -3 2 3 ! |__ _ | r=remainder(A*r , 3); 2 -2 | r=r(3,1)+r(2,1)*2+r(1,1)*4 End; OUTPUT KEY r = 21 8 11 17 10 16 19 7; 39 Journal of Theoretical and Applied Information Technology © 2005 JATIT. All rights reserved. www.jatit.org Encryption mechanism; Plain Text avn 10 31 23 Key: 21 08 11 Total : 31 39 34 %36 31 3 34 Cipher v 03 y kr 20 27 17 10 37 37 01 01 01 01 is 18 28 16 19 34 47 34 11 yb h 17 07 24 24 o n 23 21 44 08 08 I Decryption mechanism: Cipher 31 3 34 01 01 34 11 24 08 +36 0 36 0 36 36 0 36 0 36 total 31 39 34 37 37 34 47 24 44 Key 21 08 11 17 10 16 19 07 21 Difference 10 31 23 20 27 18 28 17 23 Plain text a v n k r i s h n . 3. Arithmetic Coding It would appear that Huffman or ShannonFano coding is the perfect means of compressing data. However, this is *not* the case. As mentioned above, these coding methods are optimal when and only when the symbol probabilities are integral powers of 1/2, which is usually not the case. The technique of *arithmetic coding* does not have this restriction: It achieves the same effect as treating the message as one single unit (a technique which would, for Huffman coding, require enumeration of every single possible message), and thus attains the theoretical entropy bound to compression efficiency for any source. Arithmetic coding works by representing a number by an interval of real numbers between 0 and 1. As the message becomes longer, the interval needed to represent it becomes smaller and smaller, and the number of bits needed to specify that interval increases. Successive symbols in the message reduce this interval in accordance with the probability of that symbol. The more likely symbols reduce the range by less, and thus add fewer bits to the message. 1 Codewords +-----------+-----------+-----------+ /-----\ | |8/9 YY | Detail |<- 31/32 .11111 | +-----------+-----------+<- 15/16 .1111 |Y | | too small |<- 14/16 .1110 |2/3 | YX | for text |<- 6/8 .110 +-----------+-----------+-----------+ 40 Journal of Theoretical and Applied Information Technology © 2005 JATIT. All rights reserved. www.jatit.org | | |16/27 XYY |<- 10/16 .1010 | | +-----------+ | | XY | | | | | XYX |<- 4/8 .100 | |4/9 | | | +-----------+-----------+ |||| |X | | XXY |<- 3/8 .011 | | |8/27 | | | +-----------+ | | XX | | | | | |<- 1/4 .01 | | | XXX | |||| |0 | | | +-----------+-----------+-----------+ As an example of arithmetic coding, lets consider the example of two symbols X and Y, of probabilities 0.66 and 0.33. To encode this message, we examine the first symbol: If it is a X, we choose the lower partition; if it is a Y, we choose the upper partition. Continuing in this manner for three symbols, we get the code words shown to the right of the diagram above - they can be found by simply taking an message - with longer messages the coding efficiency does indeed approach 100%. 4.Pipeline Data Compression and Encryption The two pipelines of data transmission can be designed as shown in Figure 1: The pipeline is designed to analyze the impact of encryption upon the compressed output and to see appropriate location in the interval for that particular set of symbols and turning it into a binary fraction. In practice, it is also necessary to add a special end-of-data symbol, which is not represented in this simple example. In this case the arithmetic code is not completely efficient, which is due to the shortness of the if the encryption is the favorable transform we are looking for. After compression, the compressed output is a complete random data file (noise) with its redundancy being partly removed. When the encryption algorithm is operated on the random file, the output can be expected to be another random data file. But the encryption process is 41 Journal of Theoretical and Applied Information Technology © 2005 JATIT. All rights reserved. www.jatit.org completely lossless. Therefore, its insertion will out to see the performance of different encryption not incur any loss of information, which is exactly algorithms on the transformed random data file. what we desired. Hence, the experiment is carried The results are illustrated in Table Table : Second Pipeline Experimental Results with different encryption techniques. Parameters study. for comparative Encryption: New Algorithm 1. Response time Less than 1 sec. 2. Length of the key: digits. 27 decimal 5 MIPS yrs 3. Computational overhead. –per character. 6 computations 4. Computational complexity Exponential Encryption: RSA algorithm. More than 1 sec. 5 MIPS yrs 11 computations (p=11 &q=13 depending on prime numbers. Exponential. Computer Communications and Networks: A comparative study. Even though cryptography can resolve the security problem, it also creates some drawbacks. The major part of the disadvantage is computational overhead. There is no perfect encryption algorithm so far. So people who want more secure system are trying to make the encryption algorithm more complex so that no one can break the system. But complex encryption algorithm takes more time to encrypt a message as the complexity of the crypto system increases. In other words, if you want to use more secure system, you have to spend more time on communication. Another problem is data overhead. During the securing procedure, depending on the algorithm that used to make it secure, it may generate some additional data. It is also an overhead in network point of view. Thus by simulating encryption algorithm in various network conditions, we will see how the encryption algorithm affect the network performance. For fixed band width Cryptography overhead with transmission time for data transfer X axis Data size in KB, Y axis Time in ms (Scale 1: 50) 80 70 60 50 40 30 20 10 0 4 8 12 16 20 Subs titution RSA New alg data For a fixed data size, Cryptography over head for different algorithms X –axis Data size in KB, Y- axis Time in ms (Scale 1:10). 50 40 30 20 10 0 4 8 12 16 20 Substitution RSA New alg Those two figures show that test results for different data size with the fixed bandwidth. Substitution and New algorithm has least 42 Journal of Theoretical and Applied Information Technology © 2005 JATIT. All rights reserved. www.jatit.org computational overhead than RSA algorithm. Encrypted data transmission time is also linear to the data size. New algorithm has a slight more computational overhead than substitution algorithm, but for more security. The new algorithm has equal security with RSA algorithm for less computational overhead. Computer and Digital Techniques, Vol. 141, No. 6, November, 1994, pp 327-323, ISSN: 1350-2387. [4] Welch T.A. ‘A technique for highperformance data compression’, IEEE Computer, 17(6), June 1984, pp8-19. Conclusion The increasing popularity of internet in e learning makes it highly desirable to use encryption and compression techniques. The study provides some insight into computational complexity, response time and code breaking time of some encryption algorithms. Thus the study provides some insight into overall improvement in data transmission, better bandwidth utilization, reduction in computational complexity and overall improvement in e learning technologies. Thus it can be verified the purpose of encryption and compression algorithms in virtual private networks which forms an integral component of e learning technologies. [5] G. Apostolopoulos, V. Peris, P. Pradhan, and D. Saha. Securing Electronic Commerce: Reducing the SSL Overhead. IEEE Network, pages 8--16, July/August 2000. [6] A. Frier, P. Karlton, and P. Kocher. The SSL 3.0 Protocol. Netscape Communications Corporation, November 1996. [7] D. Stinson. Cryptography: Theory and Practice. CRC Press, 1995 [8] P. Flinn and J. Jordan. Using the RSA Algorithm for Encryption and Digitial Signitures: References: [1] .Rivest R.L. et.al. ‘A method for obtaining digital signatures and publickey cryptosystems’, Commun. Of the ACM, Vol 21, No 2, February 1978. [2] .Jiang, J. ‘Pipeline algorithms of RSA data encryption and data compression’ Proceedings of ICCT’96: International Conference on Communciation Technology, IEEE Press, Vol 1, pp 10881091, 1996. [3] .Jiang, J. and Jones S. ‘Parallel design of arithmetic coding’ IEE Proceedings-E: [9] Can You Encrypt, Decrypt, Sign and Verify without Infringing the RSA Patent? 2000. http://geocities.com/einsmir/cyber_law.ht m [10] RSA security [11] http://www.seas.upenn.edu:8080/~tcom5 00/commerce/crypt_digest.htm [12] equilibrium value of MeCpG steps (,+14 deg.) [31,44]. In comparison, methylation has a significantly lower stability cost when happening at major groove positions, such as 211 and 21 base pair from dyad (mutations 9 and 12), where the roll of the nucleosome bound conformation (+10 deg.) is more compatible with the equilibrium geometry of MeCpG steps. The nucleosome destabilizing effect of cytosine methylation increases with the number of methylated cytosines, following the same position dependence as the single methylations. The multiple-methylation case reveals that each major groove meth- PLOS Computational Biology | www.ploscompbiol.org 3 November 2013 | Volume 9 | Issue 11 | e1003354 DNA Methylation and Nucleosome Positioning ylation destabilizes the nucleosome by around 1 kJ/mol (close to the average estimate of 2 kJ/mol obtained for from individual methylation studies), while each minor groove methylation destabilizes it by up to 5 kJ/mol (average free energy as single mutation is around 6 kJ/mol). This energetic position-dependence is the reverse of what was observed in a recent FRET/SAXS study [30]. The differences can be attributed to the use of different ionic conditions and different sequences: a modified Widom-601 sequence of 157 bp, which already contains multiple CpG steps in mixed orientations, and which could assume different positioning due to the introduction of new CpG steps and by effect of the methylation. The analysis of our trajectories reveals a larger root mean square deviation (RMSD) and fluctuation (RMSF; see Figures S2– S3 in Text S1) for the methylated nucleosomes, but failed to detect any systematic change in DNA geometry or in intermolecular DNA-histone energy related to methylation (Fig. S1B, S1C, S4–S6 in Text S1). The hydrophobic effect should favor orientation of the methyl group out from the solvent but this effect alone is not likely to justify the positional dependent stability changes in Figure 2, as the differential solvation of the methyl groups in the bound and unbound states is only in the order of a fraction of a water molecule (Figure S5 in Text S1). We find however, a reasonable correlation between methylation-induced changes in hydrogen bond and stacking interactions of the bases and the change in nucleosome stability (see Figure S6 in Text S1). This finding suggests that methylation-induced nucleosome destabilization is related to the poorer ability of methylated DNA to fit into the required conformation for DNA in a nucleosome. Changes in the elastic deformation energy between methylated and un-methylated DNA correlate with nucleosomal differential binding free energies To further analyze the idea that methylation-induced nucleosome destabilization is connected to a worse fit of methylated DNA into the required nucleosome-bound conformation, we computed the elastic energy of the nucleosomal DNA using a harmonic deformation method [36,37,44]. This method provides a rough estimate of the energy required to deform a DNA fiber to adopt the super helical conformation in the nucleosome (full details in Suppl. Information Text S1). As shown in Figure 2, there is an evident correlation between the increase that methylation produces in the elastic deformation energy (DDE def.) and the free energy variation (DDG bind.) computed from MD/TI calculations. Clearly, methylation increases the stiffness of the CpG step [31], raising the energy cost required to wrap DNA around the histone octamers. This extra energy cost will be smaller in regions of high positive roll (naked DNA MeCpG steps have a higher roll than CpG steps [31]) than in regions of high negative roll. Thus, simple elastic considerations explain why methylation is better tolerated when the DNA faces the histones through the major groove (where positive roll is required) that when it faces histones through the minor groove (where negative roll is required). Nucleosome methylation can give rise to nucleosome repositioning We have established that methylation affects the wrapping of DNA in nucleosomes, but how does this translate into chromatin structure? As noted above, accumulation of minor groove methylations strongly destabilizes the nucleosome, and could trigger nucleosome unfolding, or notable changes in positioning or phasing of DNA around the histone core. While accumulation of methylations might be well tolerated if placed in favorable positions, accumulation in unfavorable positions would destabilize the nucleosome, which might trigger changes in chromatin structure. Chromatin could in fact react in two different ways in response to significant levels of methylation in unfavorable positions: i) the DNA could either detach from the histone core, leading to nucleosome eviction or nucleosome repositioning, or ii) the DNA could rotate around the histone core, changing its phase to place MeCpG steps in favorable positions. Both effects are anticipated to alter DNA accessibility and impact gene expression regulation. The sub-microsecond time scale of our MD trajectories of methylated DNAs bound to nucleosomes is not large enough to capture these effects, but clear trends are visible in cases of multiple mutations occurring in unfavorable positions, where unmethylated and methylated DNA sequences are out of phase by around 28 degrees (Figure S7 in Text S1). Due to this repositioning, large or small, DNA could move and the nucleosome structure could assume a more compact and distorted conformation, as detected by Lee and Lee [29], or a slightly open conformation as found in Jimenez-Useche et al. [30]. Using the harmonic deformation method, we additionally predicted the change in stability induced by cytosine methylation for millions of different nucleosomal DNA sequences. Consistently with our calculations, we used two extreme scenarios to prepare our DNA sequences (see Fig. 3): i) all positions where the minor grooves contact the histone core are occupied by CpG steps, and ii) all positions where the major grooves contact the histone core are occupied by CpG steps. We then computed the elastic energy required to wrap the DNA around the histone proteins in unmethylated and methylated states, and, as expected, observed that methylation disfavors DNA wrapping (Figure 3A). We have rescaled the elastic energy differences with a factor of 0.23 to match the DDG prediction in figure 2B. In agreement with the rest of our results, our analysis confirms that the effect of methylation is position-dependent. In fact, the overall difference between the two extreme methylation scenarios (all-in-minor vs all-in-major) is larger than 60 kJ/mol, the average difference being around 15 kJ/ mol. We have also computed the elastic energy differences for a million sequences with CpG/MeCpG steps positioned at all possible intermediate locations with respect to the position (figure 3B). The large differences between the extreme cases can induce rotations of DNA around the histone core, shifting its phase to allow the placement of the methylated CpG steps facing the histones through the major groove. It is illustrative to compare the magnitude of CpG methylation penalty with sequence dependent differences. Since there are roughly 1.5e88 possible 147 base pairs long sequence combinations (i.e., (4n+4(n/2))/2, n = 147), it is unfeasible to calculate all the possible sequence effects. However, using our elastic model we can provide a range of values based on a reasonably large number of samples. If we consider all possible nucleosomal sequences in the yeast genome (around 12 Mbp), the energy difference between the best and the worst sequence that could form a nucleosome is 0.7 kj/mol per base (a minimum of 1 kJ/mol and maximum of around 1.7 kJ/mol per base, the first best and the last worst sequences are displayed in Table S3 in Text S1). We repeated the same calculation for one million random sequences and we obtained equivalent results. Placing one CpG step every helical turn gives an average energetic difference between minor groove and major groove methylation of 15 kJ/ mol, which translates into ,0.5 kJ/mol per methyl group, 2 kJ/ mol per base for the largest effects. Considering that not all nucleosome base pair steps are likely to be CpG steps, we can conclude that the balance between the destabilization due to CpG methylation and sequence repositioning will depend on the PLOS Computational Biology | www.ploscompbiol.org 4 November 2013 | Volume 9 | Issue 11 | e1003354 DNA Methylation and Nucleosome Positioning Figure 3. Methylated and non-methylated DNA elastic deformation energies. (A) Distribution of deformation energies for 147 bplong random DNA sequences with CpG steps positioned every 10 base steps (one helical turn) in minor (red and dark red) and major (light and dark blue) grooves respectively. The energy values were rescaled by the slope of a best-fit straight line of figure 2, which is 0.23, to por la lectura a través de la lectura de la prensa. La educación en los medios las fuerzas dispersas en función de los soportes mediáticos y orientarse más hacia la educación en medios que al dominio adquiere pleno derecho y entidad en la sección sexta titulada «competencias sociales y cívi- técnico de los aparatos. cas» que indica que «los alum- nos deberán ser capaces de juz- gar y tendrán espíritu crítico, lo que supone ser educados en los las programaciones oficiales, ya que, a lo largo de un medios y tener conciencia de su lugar y de su influencia estudio de los textos, los documentalistas del CLEMI en la sociedad». han podido señalar más de una centena de referencias a la educación de los medios en el seno de disciplinas 4. Un entorno positivo como el francés, la historia, la geografía, las lenguas, Si nos atenemos a las cifras, el panorama de la las artes plásticas : trabajos sobre las portadas de educación en medios es muy positivo. Una gran ope- prensa, reflexiones sobre temas mediáticos, análisis de ración de visibilidad como la «Semana de la prensa y publicidad, análisis de imágenes desde todos los ángu- de los medios en la escuela», coordinada por el CLE- los, reflexión sobre las noticias en los países europeos, MI, confirma año tras año, después de 17 convocato- información y opinión rias, el atractivo que ejerce sobre los profesores y los Esta presencia se constata desde la escuela mater- alumnos. Concebida como una gran operación de nal (2 a 6 años) donde, por ejemplo, se le pregunta a complementariedad entre la escuela y los profesiona- los niños más pequeños si saben diferenciar entre un les de los medios, alrededor del aprendizaje ciudada- periódico, un libro, un catálogo, a través de activida- no de la comunicación mediática, este evento moviliza des sensoriales, si saben para qué sirve un cartel, un durante toda una semana un porcentaje elevado de periódico, un cuaderno, un ordenador si son capa- centros escolares que representan un potencial de 4,3 ces de reconocer y distinguir imágenes de origen y de millones de alumnos (cifras de 2006). Basada en el naturaleza distintas. Podríamos continuar con más voluntariado, la semana permite desarrollar activida- ejemplos en todos los niveles de enseñanza y práctica- des más o menos ambiciosas centradas en la introduc- Páginas 43-48 ción de los medios en la vida de la escuela a través de la instalación de kioscos, organización de debates con profesionales y la confección por parte de los alumnos de documentos difundidos en los medios profesionales. Es la ocasión de dar un empujón a la educación en medios y de disfrutarlos. Los medios –un millar en 2006– se asocian de maneras diversas ofreciendo ejemplares de periódicos, acceso a noticias o a imágenes, proponiendo encuentros, permitiendo intervenir a los jóvenes en sus ondas o en sus columnas Esta operación da luz al trabajo de la educación en medios y moviliza a los diferentes participantes en el proyecto. 5. La formación de los docentes La formación es uno de los pilares principales de la educación en los medios. Su función es indispensable ya que no se trata de una disciplina, sino de una enseñanza que se hace sobre la base del voluntariado y del compromiso personal. Se trata de convencer, de mostrar, de interactuar. En primer lugar es necesario incluirla en la formación continua de los docentes, cuyo volumen se ha incrementado desde 1981 con la aparición de una verdadera política de formación continua de personal. Es difícil dar una imagen completa del volumen y del público, pero si nos atenemos a las cifras del CLEMI, hay más de 24.000 profesores que han asistido y se han involucrado durante 2004-05. 5.1. La formación continua En la mayoría de los casos, los profesores reciben su formación en contextos cercanos a su centro de trabajo, o incluso en este mismo. Después de una política centrada en la oferta que hacían los formadores, se valora más positivamente la demanda por parte del profesorado, ya que sólo así será verdaderamente fructífera. Los cursos de formación se repartieron en varias categorías: desde los formatos más tradicionales (cursos, debates, animaciones), hasta actividades de asesoramiento y de acompañamiento, y por supuesto los coloquios que permiten un trabajo en profundidad ya que van acompañados de expertos investigadores y profesionales. Citemos, por ejemplo en 2005, los coloquios del CLEMI-Toulouse sobre el cine documental o el del CLEMI-Dijon sobre «Políticos y medios: ¿connivencia?». Estos coloquios, que forman parte de un trabajo pedagógico regular, reagrupan a los diferentes participantes regionales y nacionales alrededor de grandes temas de la educación en medios y permiten generar nuevos conocimientos de aproximación y una profundización. Páginas 43-48 Hay otro tipo de formación original que se viene desarrollando desde hace menos tiempo, a través de cursos profesionales, como por ejemplo, en el Festival Internacional de Foto-periodismo «Visa para la imagen», en Perpignan. La formación se consolida en el curso, da acceso a las exposiciones, a las conferencias de profesionales y a los grandes debates, pero añade además propuestas pedagógicas y reflexiones didácticas destinadas a los docentes. Estas nuevas modalidades de formación son también consecuencia del agotamiento de la formación tradicional en las regiones. Los contenidos más frecuentes en formación continua conciernen tanto a los temas más clásicos como a los cambios que se están llevando a cabo en las prácticas mediáticas. Así encontramos distintas tendencias para 2004-05: La imagen desde el ángulo de la producción de imágenes animadas, el análisis de la imagen de la información o las imágenes del J.T. La prensa escrita y el periódico escolar. Internet y la información en línea. Medios y educación de los medios. 5.2 La formación inicial La formación inicial está aun en un grado muy ini- cial. El hecho de que la educación en medios no sea una disciplina impide su presencia en los IUFM (Institutos Universitarios de Formación de Maestros) que dan una prioridad absoluta a la didáctica de las disciplinas. En 2003, alrededor de 1.400 cursillistas sobre un total de 30.000 participaron en un momento u otro de un módulo de educación en medios. Estos módulos se ofrecen en función del interés que ese formador encuentra puntualmente y forman parte a menudo de varias disciplinas: documentación, letras, historia-geografía Estamos aún lejos de una política concertada en este dominio. La optativa «Cine-audiovisual» ha entrado desde hace muy poco tiempo en algunos IUFM destinada a obtener un certificado de enseñanza de la opción audiovisual y cine. Internet tiene cabida también en los cursos de formación inicial, recientemente con la aparición de un certificado informático y de Internet para los docentes, dirigido más a constatar competencias personales que a valorar una aptitud para enseñarlos. 6. ¿Y el futuro? El problema del futuro se plantea una vez más por la irrupción de nuevas técnicas y nuevos soportes. La difusión acelerada de lo digital replantea hoy muchas cuestiones relativas a prácticas mediáticas. Muchos Comunicar, 28, 2007 47 Comunicar, 28, 2007 Enrique Martínez-Salanova '2007 para Comunicar 48 trabajos que llevan el rótulo de la educación en medios solicitan una revisión ya que los conceptos cambian. La metodología elaborada en el marco de la educación en medios parece incluso permitir la inclinación de la sociedad de la información hacia una sociedad del conocimiento, como defiende la UNESCO. En Francia, se necesitaría unir las fuerzas dispersas en función de los soportes mediáticos y orientarse más hacia la educación en medios que al dominio técnico de los aparatos. Los avances recientes en el reconocimiento de estos contenidos y las competencias que supondrían podrían permitirlo. Referencias CLEMI/ACADEMIE DE BORDEAUX (Ed.) (2003): Parcours médias au collège: approches disciplinaires et transdisciplinaires. Aquitaine, Sceren-CRDP. GONNET, J. (2001): Education aux médias. Les controverses fécondes. Paris, Hachette Education/CNDP. SAVINO, J.; MARMIESSE, C. et BENSA, F. (2005): L’éducation aux médias de la maternelle au lycée. Direction de l’Enseignement Scolaire. Paris, Ministère de l’Education Nationale, Sceren/CNDP, Témoigner. BEVORT, E. et FREMONT, P. (2001): Médias, violence et education. Paris, CNDP, Actes et rapports pour l’éducation. – www.clemi.org: fiches pédagogiques, rapports et liens avec les pages régionales/académiques. – www.ac-nancy-metz.fr/cinemav/quai.html: Le site «Quai des images» est dédié à l’enseignement du cinéma et de l’audiovisuel. – www.france5.fr/education: la rubrique «Côté profs» a une entrée «education aux médias». – www.educaunet.org: Programme européen d’éducation aux risques liés à Internet. dResedfeleexliobnuetsacón Páginas 43-48
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