Art on Japanese Art History Essay Example for Free

Art on Japanese Art History Essay How can the artistic medium one chooses to use to express oneself determine whether or not it is truly art? While digital artists’ artistic ability is often questioned and the credit is given to the computer being used, the art itself springs from the mind of the digital artist. I can say this with personal fervor: Digital art is truly in essence a form of art that merely takes advantage of the innovations of modern technology. Digital Art isn’t computer-generated. While it might involve using tools offered by specialized computer programs a computer doesn’t do the thinking for you, and the creative ideas put forth are of the artist’s mind. Digital artist’s only use computer tools to convey their designs, all of the creative credibility should be given to the artist himself. Should the canvas the Mona Lisa was painted on be considered the creator of the masterpiece or rather Leonardo Da Vinci? Painters that stick to canvas are limiting themselves to the paint they use and the cotton woven fibers of their canvas. Why purposely choose to ignore the modern day tools that are given to you and condescendingly look down upon those who choose to utilize them? Over the years, I have spent a lot of my own time experimenting in the depths of digital art. Many times, I have used the computer as a medium for self expression; from creating to pictures on Microsoft paint as a child to experimenting with specialized software such as Adobe Photoshop. I have a deep and passionate love for creating and expressing myself through artwork on the computer. I one day aspire to have a profession in the field of digital art, such as a Graphic Designer. Because of this, I am very offended by the comments I hear from â€Å"traditional artists† that condescend digital art for its use of the computer as the artistic medium. When I hear comments that degrade digital artwork to computer-generated images, as though the computer itself designed the art I feel enraged and cheated. The other day a friend of mine ignorantly explained to me that she could, given the proper software, create her own masterpiece without any prior experience in digital art, as though anyone if given the proper software could instantaneously create masterpieces, when really there is so much more to digital art than computer software or the computer itself. It’s about one’s individual artistic talents. To me that would be the equivalent of saying that if I were given a canvas and a paintbrush I could instantaneously create a masterpiece, which I know is false and ignorant. Art is â€Å"the use of skill and imagination in the creation of aesthetic objects, environments, or experiences that can be shared with others† (Britannica). Digital art is a general term for a range of artistic works and practices that use digital technology as an essential part of the creative and/or presentation process. There are many different employment fields in digital art. A couple of examples are graphic design and web design. Graphic design is the process and art of combining text and graphics and communicating an effective message in the design of logos, graphics, brochures, newsletters, posters, signs, and any other type of visual communication. Famous Graphic Designer, Milton Glaser, says â€Å"to design is to communicate clearly by whatever means you can control or master. † A graphic designer would meet with his/her clients and discuss the type of visual communication the client is interested in. The client may provide a general idea for the design, but the creative options are left for the designer to decide how to best portray the message of the client. The designer would then either sketch out a design to scan on to the computer for further alterations or go directly to the computer software in order to design the desired product. The designer would then verify with the client for satisfaction of the product. Web Design is the art and process of creating a single Web page or entire Web sites and may involve both the aesthetics and the mechanics of a Web site’s operation although primarily it focuses on the look and feel of the Web site the design elements. â€Å"To be effective, the interfaces for online information systems must be as rich and flexible as the physical environments they replace. They must not only supply a direct path to reach the users goals, but must be able to accommodate different approaches to the task. This means that the interface design must not only organize the content for easy access, but must incorporate the right combination of technologies and interaction techniques to allow the user to work in their own style† (Quesenbery). A Web Designer would be sought out by a client in need of assistance in designing a website or website layout, usually for advertising and communicative purposes of the client. Like in Graphic design, the client may provide the designer with a general idea or guideline for the product, however, web designers must understand the dynamics of coding and html. Traditional art is understood to include things such as paintings, sculptures, and hand-drawings; basically any art which involves physical activity, usually of the hands. Famous Traditional Artists include: Leonardo DaVinci, Vincent Van Gough, and Andy Warhol. These artists use drawings and paintings as their forms of self expression which led to their innovative masterpieces: the Mona Lisa, Starry Night, and Pop Art, respectively. Traditional artists often look down upon the usage of the computer as the creative medium utilized when expressing oneself in art. Some believe that using a computer negates the creative ability of the artist and is the less credible form of art. Using computers in order to create art is sometimes seen as the easier method involving little artistic ability. â€Å"For artists diving into a new technology, it is a triple short-cut to mastery: you get a free ride on the novelty of the medium; there are no previous masters to surpass; and after a few weeks, you are the master† (Brand). There is a certain type of beauty in a hand-painted piece of art. The same is true for a masterfully drawn illustration. For this there is no substitute. Traditional art is the oldest form of art and could be considered the foundation of art. Many people consider this form of art to require the highest level of skill and creative ability, and that there is no other type of art form that can surpass it. There are a large number of people that believe this form of art is most vital, and that digital art simply shouldn’t be considered art due to the use of technology rather than their hands. Opponents of digital art argue that there is no skill in â€Å"pointing and clicking† on a computer screen. â€Å"I would rather choose the painting of a monkey over anything generated electronically, because I am more fascinated by the direct evidence of a mind at work than I am by the output of machines† (Glenn). Because of this belief, there is a good bit of animosity between the two different sects. Traditional artists feel as if they are protecting art in its truest form, whereas digital artists feel as if they are exposing the world to a newer and more advanced form of art infinitely full of possibilities. While traditional art is the older and more revered art form, that doesn’t mean that digital art is any less of an art. Both art forms require talent, precision, technique, and creativity from the artist. Digital artists are just as legitimate of artists as traditional artists. It is simply ignorant and petty to distinguish digital art as separate from true art in essence. Yes, computers are used as the medium for expression, however, like previously stated, that doesn’t mean that the computer creates the ideas and designs. The designs and creativity come from the artist and the computer is simply another way to release the idea from the artist’s mind, similar to a piece of paper or canvas. Digital art should be just as revered as traditional art because the amount of creativity and artistic ability is equal in both forms.

Database security and encryption

Database security and encryption Introduction Organisations are increasingly relying on the distributed information systems to gain productivity and efficiency advantages, but at the same time are becoming more vulnerable to security threats. Database systems are an integral component of this distributed information system and hold all the data which enables the whole system to work. A database can be defined as a shared collection of logically related data and a description of this data, designed to meet the information needs of an organization. A database system is considered as a collection of related data, database management system (DBMS) a software that manages (define, create and maintain) and controls the access to the database, and a collection of database application(s) a program that interacts with the database at some point in its execution (typical example is a SQL statement) along with the DBMS and the database itself [1]. Organisations have adopted database systems as the key data management technology for decision-making and day-to-day operations. Databases are designed to hold large amounts of data and management of data involves both defining structures for storage of information and providing mechanisms for manipulation of information. As the data is to be shared among several users the system must avoid anomalous results and ensure the safety of the information stored despite system crashes and attempts at unauthorized access. The data involved here can be highly sensitive or confidential, thus making the security of the data managed by these systems even more crucial as any security breach does not affect only a single application or user but can have disastrous consequences on the entire organisation. A number of security techniques have been suggested over the period of time to tackle the security issues. These can be classified as access control, inference control, flow control, and encryptio n. 1.1 A Short History Starting from the day one when database applications were build using hierarchical and network systems to todays date when we have so many different database systems like relational databases (RDBMS), object-oriented databases (OODBMS), object-relational databases (ORDBMS), eXtended Query (XQUERY); one factor which was, is, and will be of the utmost importance is the security of the data involved. Data always has been a valuable asset for companies and must be protected. Organizations spend millions these days in order to achieve the best security standards for the DBMS. Most of an organizations sensitive and proprietary data resides in a DBMS, thus the security of the DBMS is a primary concern. When we talk of securing a DBMS, this is with respect to both the internal and the external users. The internal users are the organization employees like database administrators, application developers, and end users who just use the application interface, which fetch its data from one of the databases and the external users can be the employees who do not have access to the database or an outsider who has nothing to do with the organization. The other factors which has made data security more crucial is the recent rapid growth of the web based information systems and applications and the concept of mobile databases. Any intentional or accidental event that can adversely affect a database system is considered as a threat to database and database security can be defined as a mechanism that protects the database against such intentional or accidental threats. Security breaches can be classified as unauthorized data observation, incorrect data modification, and data unavailability, which can lead to loss of confidentiality, availability, integrity, privacy, and theft and fraud. Unauthorized data observation results in disclosure of information to users who might not be entitled to have access to such kind of information. Incorrect data modification intentional or unintentional leaves the database in an incorrect state. Data can hamper the functionality of an entire organization in a proper way if not available when needed. Thus the security in terms of databases can be broadly classified into access security and internal security. Access security refers to the mechanisms implemented to restrict any sort of unauthorized access to the database; examples can be authorization methods such as every user has a unique username and password to establish him as a legitimate user when trying to connect to the database. When the user tries to connect to the database the login credentials will be checked against a set of usernames and password combinations setup under a security rule by a security administrator. Internal security can be referred to as an extra level of security, which comes into picture if someone has already breached the access security such as getting hold of a valid username and password, which can help getting access to the database. So the security mechanism implemented within the database such as encrypting the data inside the database can be classed as internal security, which prevents the data to be compromised even if someone has got unauthorized access to the database. Every organization needs to identify the threats they might be subjected to and the subsequently appropriate security plans and countermeasures should be taken, taking into consideration their implementation costs and effects on performance. Addressing these threats helps the enterprise to meet the compliance and risk mitigation requirements of the most regulated industries in the world. 1.2 How Databases are Vulnerable According to David Knox [2], Securing the Database may be the single biggest action an organization can take, to protect its assets. Most commonly used database in an enterprise organization is relational database. Data is a valuable resource in an enterprise organization. Therefore they have a very strong need of strictly controlling and managing it. As discussed earlier it is the responsibility of the DBMS to make sure that the data is kept secure and confidential as it the element which controls the access to the database. Enterprise database infrastructure is subject to an overwhelming range of threats most of the times. The most common threats which an Enterprise Database is exposed to are: Excessive Privilege Abuse when a user or an application has been granted database access privileges which exceeds the requirements of their job functions. For example an academic institute employee whose job only requires only the ability to change the contact information for a student can also change the grades for the student. Legitimate Privilege Abuse legitimate database access privileges can also be abused for malicious purposes. We have two risks to consider in this situation. The first one is confidential/sensitive information can be copied using the legitimate database access privilege and then sold for money. The second one and perhaps the more common is retrieving and storing large amounts of information on client machine for no malicious reason, but when the data is available on an endpoint machine rather than the database itself, it is more susceptible to Trojans, laptop theft, etc. Privilege Elevation software vulnerabilities which can be found in stored procedures, built-in functions, protocol implementations or even SQL statements. For example, a software developer can gain the database administrative privileges by exploiting the vulnerabilities in a built-in function. Database Platform Vulnerabilities any additional services or the operating system installed on the database server can lead to an authorized access, data corruption, or denial of service. For example the Blaster Worm which took advantage of vulnerability in Windows 2000 to create denial of service. SQL Injection the most common attack technique. In a SQL injection attack, the attacker typically inserts unauthorized queries into the database using the vulnerable web application input forms and they get executed with the privileges of the application. This can be done in the internal applications or the stored procedures by internal users. Access to entire database can be gained using SQL injection Weak Audit a strong database audit is essential in an enterprise organization as it helps them to fulfill the government regulatory requirements, provides investigators with forensics link intruders to a crime deterring the attackers. Database Audit is considered as the last line of database defense. Audit data can identify the existence of a violation after the fact and can be used to link it to a particular user and repair the system in case corruption or a denial of service attack has occurred. The main reasons for a weak audit are: it degrades the performance by consuming the CPU and disk resources, administrators can turn off audit to hide an attack, organizations with mixed database environments cannot have a uniform, scalable audit process over the enterprise as the audit processes are unique to database server platform Denial of Service access to network applications or data is denied to the intended users. A simple example can be crashing a database server by exploiting vulnerability in the database platform. Other common denial of service techniques are data corruption, network flooding, server resource overload (common in database environments). Database Protocol Vulnerabilities SQL Slammer worm took advantage of a flaw in the Microsoft SQL Server protocol to force denial of service conditions. It affected 75,000 victims just over 30 minutes dramatically slowing down general internet traffic. [Analysis of BGP Update Surge during Slammer Worm Attack] Weak Authentication obtaining legitimate login credentials by improper way contributes to weak authentication schemes. The attackers can gain access to a legitimate users login details by various ways: by repeatedly entering the username/password combination until he finds the one which works (common or weak passwords can be guessed easily), by convincing someone to share their login credentials, by stealing the login credentials by copying the password files or notes. Backup Data Exposure there are several cases of security breaches involving theft of database backup tapes and hard disks as this media is thought of as least prone to attack and is often completely unprotected form attack [3]. All these security threats can be accounted for unauthorized data observation, incorrect data modification and data unavailability. A complete data security solution must take into consideration the secrecy/confidentiality, integrity and availability of data. Secrecy or confidentiality refers to the protection of data against unauthorized disclosure, integrity refers to prevention of incorrect data modification and availability refers to prevention of hardware/software errors and malicious data access denials making the database unavailable. 1.3 Security Techniques As organizations increase their adoption of database systems as the key data management technology for day-to-day operations and decision-making, the security of data managed by these systems has become crucial. Damage and misuse of data affect not only a single user or application, but may have disastrous consequences on the entire organization. There are four main control measures which can be used to provide security of data in databases. These are: Access Control Inference Control Flow Control Data Encryption Chapter 2 Literature Review Secure and secret means of communication has been always desired for in the field of database systems. There is always a possibility of interception by a party outside of the sender-receiver domain when data is transmitted. Modern digital-based encryption methods form the basis of todays world database security. Encryption in its earlier days was used by military and government organizations to facilitate secret information but in present times it is used for protecting information within many kinds of civilian systems. In 2007 the U.S. government reported that 71% of companies surveyed utilized encryption or some of their data in transit [4]. 2.1 Encryption Encryption is defined as the process of transforming information (plaintext) using an encryption algorithm (cipher) into unreadable form (encrypted information called as ciphertext) making it inaccessible to anyone without possessing special knowledge to decrypt the information. The encoding of the data by a special algorithm that renders the data unreadable by any program without the decryption key, is called encryption [1]. The code and cipher are the two methods of encrypting data. The encryption of data or a message is accomplished by one, or both, of the methods of encoding or enciphering. Each involves distinct methodologies and the two are differentiated by the level at which they are carried out. Encoding is performed at the word or block level and deals with the manipulation of groups of characters. Enciphering works at the character level. This includes scrambling individual characters in a message, referred to as transposition, and substitution, or replacing characters with others. Codes generally are designed to replace entire words or blocks of data in a message with other words or blocks of data. Languages can be considered codes, since words and phrases represent ideas, objects, and actions. There are codes that substitute entire phrases or groups of numbers or symbols with others. A single system may employ both levels of encoding. For example, consider a code encryption scheme as follows: the = jam, man = barn, is = fly, dangerous = rest. Then the message, the man is dangerous, would read in encrypted form, jam barn fly rest. Although overly-simplistic, this example illustrates the basis of codes. With the advent of electrical-based communications, codes became more sophisticated in answer to the needs of the systems. For example, the inventions of Morse code and the telegraph dictated a need for secure transmission that was more sophisticated. Codes are very susceptible to breaking and possess a large exposure surface with regard to interception and decryption via analysis. Also, there are no easily-implemented means by which to detect breaches in the system. The other method of encryption is the cipher. Instead of replacing words or blocks of numbers or symbols with others, as does the code, the cipher replaces individual or smaller sets of letters, numbers, or characters with others, based on a certain algorithm and key. Digital data and information, including vi deo, audio, and text, can be separated into groups, or blocks, of bits, and then manipulated for encryption by such methods as XOR (exclusive OR), encoding-decoding, and rotation. As an example, let us examine the basics of the XOR method. Here, a group of bits (e.g., a byte) of the data is compared to a digital key, and the exclusive-or operation is performed on the two to produce an encrypted result. Figure 2 illustrates the process. Figure 2: The XOR process for Encryption When the exclusive-or operation is performed on the plaintext and key, the ciphertext emerges and is sent. The receiver performs the exclusive-or operation on the ciphertext and the same key, and the original plaintext is reproduced [5]. Encryption can be reversible and irreversible. Irreversible techniques do not allow the encrypted data to be decrypted, but at the same time the encrypted data can be used to obtain valid statistical information. Irreversible techniques are rarely used as compared to the reversible ones. The whole process of transmitting data securely over an insecure network system is called as cryptosystem that includes à » An encryption key to encrypt the data (plaintext) à » An encryption algorithm that transforms the plaintext into encrypted information (ciphertext) with the encryption key à » A decryption key to decrypt the ciphertext à » A decryption algorithm that transforms the ciphertext back into plaintext using the decryption key [1]. 2.2 Encryption Techniques The goals in digital encryption are no different than those of historical encryption schemes. The difference is found in the methods, not the objectives. Secrecy of the message and keys are of paramount importance in any system, whether they are on parchment paper or in an electronic or optical format [5]. Various encryption techniques are available and broadly can be classified into two categories; asymmetric and symmetric encryption. In symmetric encryption the sender and receiver share the same algorithm and key for encryption and decryption and depends on safe communication network for encryption key exchange whereas in asymmetric encryption uses different keys for encryption and decryption. Asymmetric encryption gave birth to the concept of public and private keys and is preferred to symmetric encryption being more secure [1], [5]. 2.2.1 Symmetric Encryption Symmetric encryption also known as single-key encryption or conventional encryption was the only encryption and by far the most widely used of the two types before the concept of public-key encryption came into picture. The figure below illustrates the symmetric encryption process. The original message (plaintext) is converted into apparently random information (ciphertext) using an algorithm and a key. The key is a value independent of the plaintext. The algorithm produces different outputs for specific keys used at the time i.e. the output of the algorithm changes if the key is changed. The ciphertext produced is then transmitted and is transformed back to the original plaintext by using a decryption algorithm and the same key that was used for encryption. Figure: Simplified Model of Conventional Encryption [7 page 22] The model can be better understood by the following example. A source produces a message X = [X1, X2, X3 à ¢Ã¢â€š ¬Ã‚ ¦XM] in plaintext. The M elements of X are letters in some finite alphabet. The alphabet usually consisted of 26 capital letters traditionally but nowadays; binary alphabet {0,1} is used. An encryption key K = [K1, K2, K3 à ¢Ã¢â€š ¬Ã‚ ¦.KJ] is generated and is shared between the sender and the receiver using a secure channel. Also a third party can generate the encryption key and securely deliver it to both the sender and the receiver. Using the plaintext X and the encryption key K as input, the encryption algorithm produces the ciphertext Y = [Y1, Y2, Y3 à ¢Ã¢â€š ¬Ã‚ ¦.YN] as Y = EK(X) where E is the encryption algorithm and the ciphertext Y is produced as the function of the plaintext X using E. At the receivers end the ciphertext is converted back to the plaintext as X = DK(Y) where D is the decryption algorithm. Figure: Model of Conventional Cryptosystem [7 page 23] The common symmetric block ciphers are Data Encryption Standard (DES), Triple DES, and Advanced Encryption Standard (AES) 2.2.1.1 The Data Encryption Standard Data Encryption Standard has been used in the most widely used encryption schemes including Kerberos 4.0. The National Bureau of Standards adopted it as a standard in 1977 [7]. DES operates on 64-bit blocks using a 56-bit key. Like other encryption schemes, in DES there are two inputs to the encryption function, the plaintext to be encrypted and the key. The plaintext should be of 64 bits in length and the key length is 56 bits obtained by stripping off the 8 parity bits, ignoring every eighth bit from the given 64-bit key. The output from the algorithm after 16 rounds of identical operations is the 64-bit block of ciphertext. A suitable combination of permutations and combinations (16 times) on the plaintext is the basic building block of the DES. Same algorithm is used for both encryption and decryption except for processing the key schedule in the reverse order [6], [7]. The 64-bit plaintext is passed through an initial permutation (IP) that produces a permuted input by rearranging the bits. This is followed by16 rounds of the same function, which involves both permutation and substitution functions. The last round results in the output consisting of 64-bits that are a function of the input plaintext and the key. The left and the right halves of the output are swapped to produce the preoutput. The preoutput is passed through a final permutation (IP-1), an inverse of the initial permutation function to achieve the 64-bit ciphertext. The overall process for DES is explained in the diagram below Figure: General Depiction of DES Encryption Algorithm [7 page 67] The right hand side of the diagram explains how the 56-bit key is used during the process. The key is passed through a permutation function initially and then for each of the 16 rounds a subkey (Ki) is generated, by combining left circular shift and a permutation. For every round the permutation function is same, but the subkey is different because of the repeated iteration of the key bits. Since the adoption of DES as a standard, there have always been concerns about the level of security provided by it. The two areas of concern in DES are the key length and that the design criteria for the internal structure of the DES, the S-boxes, were classified. The issue with the key length was, it was reduced to 56 bits from 128 bits as in the LUCIFER algorithm [add a new reference], which was the base for DES and everyone suspected that this is an enormous decrease making it too short to withstand brute-force attacks. Also the user could not be made sure of any weak points in the internal structure of DES that would allow NSA to decipher the messages without the benefit of the key. The recent work on differential cryptanalysis and subsequent events indicated that the internal structure of DES is very strong. 2.2.1.2 Triple DES Triple DES was developed as an alternative to the potential vulnerability of the standard DES to a brute-force attack. It became very popular in Internet-based applications. Triple DES uses multiple encryptions with DES and multiple keys as shown in the figure [below]. Triple DES with two keys is relatively preferred to DES but Triple DES with three keys is preferred overall. The plaintext P is encrypted with the first key K1, then decrypted with the second key K2 and then finally encrypted again with the third key K3.According to the figure the ciphertext C is produced as C = EK3[DK2[EK1[P]]] These keys need to be applied in the reverse order while decrypting. The ciphertext c is decrypted with the third key K3 first, then encrypted with the second key K2, and then finally decrypted again with the first key K1; also called as Encrypt-Decrypt-Encrypt (EDE) mode, producing the plaintext P as P = DK1[EK2[DK3[C]]] Figure: Triple DES encryption/decryption [6 page 72] 2.2.1.3 Advanced Encryption Standard 2.3 Encryption in Database Security Organizations are increasingly relying on, possibly distributed, information systems for daily business; hence they become more vulnerable to security breaches even as they gain productivity and efficiency advantages. Database security has gained a substantial importance over the period of time. Database security has always been about protecting the data data in the form of customer information, intellectual property, financial assets, commercial transactions, and any number of other records that are retained, managed and used on the systems. The confidentiality and integrity of this data needs to be protected as it is converted into information and knowledge within the enterprise. Core enterprise data is stored in relational databases and then offered up via applications to users. These databases typically store the most valuable information assets of an enterprise and are under constant threat, not only from the external users but also from the legitimate users such as trusted ins iders, super users, consultants and partners or perhaps their unprotected user accounts that compromise the system and take or modify the data for some inappropriate purpose. To begin with, classifying the types of information in the database and the security needs associated with them is the first and important step. As databases are used in a multitude of ways, it is useful to have some of the primary functions characterized in order to understand the different security requirements. A number of security techniques have been developed and are being developed for database security, encryption being one of them. Encryption is defined as the process of transforming information (plaintext) using an encryption algorithm (cipher) into unreadable form (encrypted information called as ciphertext) making it inaccessible to anyone without possessing special knowledge to decrypt the information. The encoding of the data by a special algorithm that renders the data unreadable by any program without the decryption key, is called encryption [1]. 2.3.1 Access Encryption There are multiple reasons for access control to confidential information in enterprise computing environments being challenging. Few of them are: First, the number of information services in an enterprise computing environment is huge which makes the management of access rights essential. Second, a client might not know which access rights are necessary in order to be granted access to the requested information before requesting access. Third, flexible access rights including context-sensitive constraints must be supported by access control Access control schemes can be broadly classified in two types: proof-based and encryption-based access control schemes. In a proof-based scheme, a client needs to assemble some access rights in a proof of access, which demonstrates to a service that the client is authorized to access the requested information. Proof-based access control is preferred to be used for scenarios where client specific access rights required are flexible. It becomes easy to include support for constraints if the access rights are flexible. However, it is not the same case for covert access requirements. According to the existing designs, it is assumed that a service can inform a client of the nature of the required proof of access. The service does not need to locate the required access rights, which can be an expensive task, in proof-based access control scheme. [9] In an encryption-based access-control scheme, confidential information is provided to any client in an encrypted form by the service. Clients who are authorized to access the information have the corresponding decryption key. Encryption-based access-control scheme is attractive for scenarios where there are lots of queries to a service shielding the service from having to run client-specific access control. As compared to proof-based access control it is straightforward to add support for covert access requirements to existing encryption-based architectures. In particular, all the information is encrypted by the service as usual, but the client is not told about the corresponding decryption key to use. The client has a set of decryption keys, the client now needs to search this set for a matching key. On the other hand, considering that key management should remain simple, it is less straightforward to add support for constraints on access rights to the proposed architectures. [10] 2.3.1.1 Encryption-Based Access Control Encryption-based access control is attractive, in case there are lots of requests for the same information, as it is independent of the individual clients issuing these requests. For example, an information item can be encrypted once and the service can use the ciphertext for answering multiple requests. However, dealing with constraints on access rights and with granularity aware access rights becomes difficult with the uniform treatment of requests. Further challenges are presented in cases of covert access requirements and service-independent access rights. The main requirements for encryption based access control are: à » Any knowledge about the used encryption key or the required decryption key must not be revealed by the encrypted information. à » For decrypting encrypted information, each value of a constraint must require a separate key that should be accessible only under the given constraint/value combination and we want a scheme that supports hierarchical constraints to make key management simple. à » The decryption key for coarse-grained information should be derivable from the key for fine-grained information to further simplify key management. à » A single decryption key will be used to decrypt the same information offered by multiple services as implied by the service-independent access rights. Because of this, same information can be accessed by a service encrypting information offered by other services in a symmetric cryptosystem. This problem can be avoided by using asymmetric cryptosystem. [8] 2.3.1.2 Encryption-Based Access Control Techniques An access-control architecture will be an ideal one if the access rights are simple to manage; the system is constrainable and is aware of granularity. The architecture also has to be asymmetric, provide indistinguishability, and be personalizable in the case of proof-based access control. Some common encryption-based access control techniques are: Identity Based Encryption An identity-based encryption scheme is specified by four randomized algorithms: à » Setup: takes a security parameter k and returns system parameters and master-key. The system parameters include a description of a finite message space m and a description of a finite ciphertext space c. Intuitively, the system parameters will be publicly known, while the master-key will be known only to the Private Key Generator (PKG). à » Extract: takes as input system parameters, master-key, and an arbitrary ID à Ã‚ µ {0,1}*, and returns a private key d. ID is an arbitrary string which is then used as a public key, and d is the corresponding private decryption key. The Extract algorithm extracts a private key from the given public key. à » Encrypt: takes as input system parameters, ID, and M à Ã‚ µ m. It returns a ciphertext C à Ã‚ µ c. à » Decrypt: takes as input system parameters, C à Ã‚ µ c, and a private key d. It returns M à Ã‚ µ m. Standard consistency constraint must be satisfied by these algorithms, especially when d is the private key generated by algorithm Extract when it is given ID as the public key, then à ¢Ã‹â€ Ã¢â€š ¬ M à Ã‚ µ m: Decrypt (params, d) = M where C = Encrypt (params, ID, M) [11] Hierarchical Identity-Based Encryption One of the first practical IBE schemes was presented by Boneh and Franklin. Gentry and Silverberg [7] introduced Hierarchical Identity-Based Encryption scheme based on Boneh and Franklins work. In HIBE, private keys are given out by a root PKG to the sub PKGs, which then in turn distribute private keys to individuals (sub PKGs) in their domains. There are IDs associated with the root PKG and the public key of an individual corresponds to these IDs, any sub PKGs on the path from the root PKG to the individual, and the individual. Public parameters are required only from the root PKG for encrypting messages. It has the advantage of reducing the amount o

SUVs: Not Just Practical Essay -- miscellaneous

SUVs: Not Just Practical Car technology is advancing quickly and unstoppably. Along with that, the concepts of some vehicles have also changed, creating new uses that consequently make them attractive for other clients. Following this tendency for more multifunctional machines, one kind of vehicle has increased its popularity as it combines the best of work vehicles and regular automobiles. Therefore, a new market has been opened for the Sport Utility Vehicles (SUVs). SUVs creators have developed such a comfortable and practical interior by placing accessories, small gadgets, devices, pleasure add-ons, and many other things we could want or need. Because of that, now it is easier than ever, for a person who owns a SUV to do activities that were not considered appropriate for these vehicles not very long ago. Examples of this are how these SUVs respond to demands regarding road trips, field trips, every day usage, usage as entertainment centers, and even in family vehicle usage. For the purpose of understanding the uses presented above it is helpful to know its definition. A SUV can be described basically as a high-performance four-wheel car built on a truck chassis, an element that gives a big part of its strength and durability. Even though, according to WordIQ.com, a SUV is a type of vehicle that combines the load-hauling and passenger-carrying capacity of a station wagon or minivan with features designed for off-road driving. In more recent years, though, the term has also grown to include vehicles with similar size and style marketed as sport utility vehicles, but do not incorporate many off-road features. The SUVs is considered to be descendent of commercial and military vehicles such as Jeep and Land Rover, starters of the genre. In the last 25 years, though, and even more in the last decade, they have become popular with urban buyers. Therefore, it has to fit the demands of urban buyers, who may use the SUVs to travel long distances. One very noticeable characteristic of today’s SUVs is that they have changed in order to be more suitable for long trips in them, keeping up with the competition for that market. Since a few years ago these cars were used almost exclusively for work, the purpose for what they were created, the manufacturers were not paying too much attention on how comfortable they would be for spending a big amount of time in ... ...umerous utilities. The SUVs can provide that, and they will continue to improve in order to fulfill the need of the buyers in the next decades, which will probably search for products with even broader uses. This appears to indicate that the SUVs are slowly becoming the vehicle of the future, for they are the most likely candidates to win in one market, that, along with many others, seems to be destined to become every time more simple. Finally, what was only a type of vehicle with work purposes is now also popular in cities and with people that would not think they needed it a few years ago. Statistics are moving towards the SUVs’ taking over the automobile market: Every year a bigger number of them being bought. Still, the exterior of the SUVs has barely changed during the last few years. This lead us to the conclusion that it is the redesign of the concept and interior of this type of car, not of the exterior, what has led to this major change of the use of it, which has been reflected on its current customers. They now not only give usefulness, but also comfort. This has led to the fact that we can do more things than ever with the every time more functional â€Å"house vehicle†.

Wedding Speech by a Childhood Friend of the Groom -- Wedding Toasts Ro

Wedding Speech by a Childhood Friend of the Groom Good afternoon, ladies and gentlemen. On behalf of the bridesmaids, I would like to thank Scott for his kind words. For once in my life, I find myself agreeing with him - they look stunning and did an excellent job today. For those of you who don't know me, my name is Jason. I’ve been Scott’s best friend for nearly 20 years. I’ve known him for a similar period. And all the time we’ve spent growing up together means that he’s had as much of a part in developing my sense of humor as anyone. So, while I have tried to make this speech funny, it’s his fault if it’s not. I have very fond memories of growing up with Scott. I’ve been his partner in crime on many a wild occasion and, in quieter times, a close confidant to whom he could tell almost anything. And I do mean anything – which has provided me with ample material for my speech this afternoon. Although I did agree not to divulge any details of the stag night, like about the Danish stripper he got chatting to in the hotel bar. So I won’t. Scott and I have done many things together during our almost life-long friendship – although they’re probably not quite as interesting to relate as the story about that Danish stripper, but I gave him my word on that one. Anyway, over the years we've built go-carts together, rode our bikes together, played football together, bunked school together, tried to... ...r. And I, as much as all of you, want that happiness for myself. Er, sorry, I mean, I want their happiness to last forever. And I do. So although I’m not actually married myself [turn to bridesmaids again], I thought it might be helpful if I offered them each a little piece of advice. Pamela: no matter how far away you are from your loved one, when you’re married, you’re never alone - because you know where my flat is. And Scott: getting married bestows upon you many, many obligations. But remember, foreplay is only optional. Ladies and gentlemen, on a final and serious note, please be upstanding and raise your glasses to my very best friend and his beautiful new wife. To Scott and Pamela.

Jarok as a Traitor :: Star Trek Defector Essays Papers

Jarok as a Traitor A creator of a web page has good intentions to display to the viewer the correct information, but there is no way to tell if the creator gives an accurate representation of the information. In the episode "The Defector", Jarok does not appear to be a traitor through his actions, but the way he represents himself clearly makes him a traitor. A traitor, as defined by Webster's Collegiate Dictionary, is one who betrays another's trust or is false to an obligation or duty. A defector is defined as one who leaves a situation often to go over to a rival one. During the course of the episode, Jarok is a traitor to the Romulans, the Federation, and his daughter, although he is labeled in the title of the episode as a defector. During the episode, Jarok physically joins with the Federation, which can lead one to believe he is a defector. He may have crossed over for the good of everyone, but he betrayed his country at an ideological level. He gave information to the Federation, including details of the Romulan fleet, technology, and offensive. "Jarok said that he had seen reports, fee receipts, and work orders for the construction of a military base." (Smith 30 Jan. 1996) He, also, stole a ship and claimed he had no other option, but there were, most likely, other options he could have resorted to. Tomalak, the head of the Romulans remarked at the end of the episode, " You see, Picard, after we dissect your enterprise for every precious bit of information, I intend to display its broken hull in the center of the Romulan capitol as a symbol of our victory. It will inspire our armies for generations to come. And serve as a warning to any other traitor who would create ripples of disloyalty." ("The Defector" 1 4 Jan. 1990) The Romulans planted misinformation knowing Jarok might betray their trust. Jarok believed he had valid information, which placed even greater value on these top secrets he shouldn't have revealed to the Federation. When one obtains information from a web page, the information may not be the truth. After betraying his own country, he could have come over to the rival to act as a defector; instead he represented himself as a traitor to the Federation. By using a false name, it seemed he wanted to conceal his true identity to the Federation.

Edvard Munch The Scream and The Sick Child Essay

Edvard Munch was born in Norway in 1863 and became a troubled artist after he was influenced by many older impressionists. Most of his work is a reflection of impressionism and tells a story that is mostly dark or consist of death, illness, anxiety, pain, or fear. His paintings also are influenced by the heartache he endured as a child watching close family members die from sickness that he survived, such as, his sister and his mother who both became ill and died of tuberculosis. The darkness continued to haunt him throughout his life and influenced his paintings as well which in turn, created a very famous artist of impressionism and symbolism. Most of his work symbolized troubles, anxiety, and a loss in someway shape or form to include death, or psychological problems such as anxiety.(Wolf,2009) Munch used paintings that signify demons and bad times rather than the happy times in peoples lives which was different and accepted. One of Edvard Munch’s first and earliest paintings, sick child, is an early example of a painting that shows sadness, sickness, and possible death. The painting is of a young girl, munch’s sister, laying in a bed straight up and hovered over by another grienving womanly figure who’s head is bowed as to only show us the top of her head. The girl looks vaguely pale with bright red long uncombed hair and a blank stare on her face. The girl is staring at a dark wall that could signify death. The women hovered over her signifies grievance and pain seeing how she is not directly looking at the girl but rather sad and depressed. Hands are not drawn in the painting but an interlocking of shapes used to signify that joining of hands is greatly illustrated, perhaps, to indicate the woman at the bedside as being her mother who dies 11 years earlier. The painting of his sister who died at the age of 15 and his mother who died of the same disease a decade earlier is an obsess ive painting that took Munch 6 different tries to master exactly the way he wanted it to be. Each version was different in different ways and told the similar story. His first version of the painting was a black and white lithograph with similar thick vertical and horizontal brushstrokes as see in the paintings he did after the first. However, each new version of The sick child, adds more story and elements in order to further depict such a dark and haunting time. Munch used dark colors and rough brushstrokes of impasto paint in his painting depicting a sadness and hard time in his life.(Esaak,2012) Happiness is not in any part of this painting and melancholic tones are also used and presented throughout, as well as, scratched surfaces made to look weathered and torn. The lithograph painting was first painting in white and black and later was changed and painted with dark and more intense colors and with more impressionism which was popular in that time and therefore was a blend of both lithograph and impressionism. (Esaak,2012) Another famous work of art done by Edvard Munc h is, The Scream. Again Munch used free,loose, and vertical brushstrokes and paints with dark intense colors. The use of semi-abstraction is also present throughout this painting. Munch used fauvism, expressionism, and surrealism in this painting. The painting definitely depicts a distoration of reality throughout. The girl in the pictures face is distorted as well as the bridge and sky around her which leaves the work to personal vision when analyzing it. Munch was influenced to paint The Scream after walking with his friends at sundown and was frightened by a terrible scream and therefore, the picture is a symbol of his fear deep inside himself. The figure with an odd shaped cartoon head, comparable to an alien, has their hands to their agonizing face as if screaming themselves in fear and the world around them seems to stop as the sky in the background looks horrifying and portrays violence.(Welford,2002) The sky is shown in red and yellow colors and the sea below is shown with the use of dark blue, greens, and black. Nature represents the swirling of the sky and the sea and the swirling represents the irony of horror. As his friends walk on not feeling the same fear as the artist, shows that the fear inside peoples heads do not affect everyone. Therefore, the irony of this painting proves that fact that only certain people will relate to what the artist is trying to portray which is fear and anxiety within ones self. The scream itself is portraying the release of tension and fear that one feels from living with the anxiety and fears.(Welford,2002) The painting also depicts the sudden onset of anxiety and fear that can come on at any given time which affects some people in crowded places or just walking along on the bridge as in this painting. The noises and screams that the artist fears is not feared or heard by others around him and therefore, not everyone can understand the fear. Edvard Munch was an excellent antinaturalist impressionist artist who used realistic views in order to capture the views of his audience. His paintings incorporate the sorrow and heartache that most humans feel as some part in their lives, others more than some. Other paintings depict the anguish of facing the demons inside when it comes to psychological problems, as well as fear and anxiety and some viewers can relate to the artists work and how he used detailed paintings to show his point of view on the subject. He used subjective content and realism to show disparity, and darkness, as well as surrealism. People were also a large part of his paintings as well as nature when trying to convey his message like he did in The sick child, and The scream. Reference Page Welford, John. â€Å"The Scream by Edvard Munch.† Artwork analysis. (2002): 1-12. Web. 16 Feb. 2013. . Wolf, Justin. â€Å"The Art Story.† Edward Munch. (2009): n. page. Web. 16 Feb. 2013. . . Zsaak, Shelley. â€Å"The Sick Child 1896.† Edvard Munch. (2012): n. page. Web. 16 Feb. 2013. .

Chameleon Essay

â€Å"Love has no culture, boundaries, race and religion. It is pure and beautiful like early morning sunrise falling in lake.† is a quote by Santosh Kalwar, who writes books about truth, love and relationships. What he expresses is that it doesn’t matter what skin color you have, as long it is real love. In the novel â€Å"Chameleon† by Ranbir Sahota we hear about a girl named Rita. Rita has problems balancing between who she wants to be, and who she is expected to be because of her race. She is desperately trying hard to be fully integrated but is finding it difficult because her family is so old fashioned. When it comes to love she doesn’t know if she should make her parents happy or follow her own heart. A first person narrator named Rita, where we have access to only her thoughts, tells the short story. Rita is the main protagonist in the novel and a daughter of an Indian Sikh. Opposite to her family, being integrated means a lot to her, and in her everyday life in England, she is trying to fit in. Her father only moved to England because some of his friends did. Therefore they don’t want to integrate simply because they don’t have the love and passion for the country. She on the other hand has graduated from Sheffield University and went to teach English in Germany. Eating white food, listing to white music and bleaching her own skin is just part of her daily life for trying to be part of the English society. The title is â€Å"Chameleon† and describes Rita and how she can blend in, even though she is dark. According to her, the Indian culture doesn’t allow women to have a voice. Her mother and father has set up an arranged marriage for her, where the men can have expectations for her, but she cant expect anything from them. Rita doesn’t have an interest towards Indian men because she sees them as brothers and boring. Therefore she is dating a white man named Mark behind her parent’s back. Even though it is against the Indian culture values and rules. Marks mom says that she doesn’t want to speak to Mark, if he is dating a girl, who isn’t Catholic. But Rita knows that his mother has a problem with her skin color: â€Å" I was fine as the token dark  friend but it was a different matter when it came to marriage† (page 99, lines 3-4). For Marks mother their relationship is fine on a friendly base but not as a love interest. His mother doesn ’t want to be seen as a racists so she is covering up her real problem by saying it is because she isn’t Catholic. In that way Marks mother is actually just like a chameleon as well as Rita. Because of their families the main problem for the couple becomes the diverse between culture and religion. They can’t be together because their cultural backgrounds’ doesn’t allow them to. Mark and Rita then rents a little house together to get some private space. To them it is their escape from the judging and controlling world into a wonderful world where all people are the same. At some point Rita is meeting with Sunjay, who is set to be her future husband according to her mom. They are laughing together and are having a good chemistry. They are talking together like equals, which you wouldn’t expect because of Rita’s description about the Indian culture where women doesn’t have a voice. They also have the same positive attitude when it comes to love between different races. Sunday’s mother and father think that he has too many white friends. Both Rita and Sunjay have integrated themselves very well and are struggling with their families putting pressure on them. Although she doesn’t wants to let her parents down she does small things to annoy them. She swears a lot and is provocative towards them in her comments some times, which is not ladylike in the Indian culture. Also on page 106 lines 7-14 where we are in her thoughts and she is imagining what would happen if she told her parents about Mark and her. She says that it is comical and it would turn into a bloodbath, which is an absurd thought to have about such an important and serious theme. Over the last six weeks Rita had seen three other men but none of them where like Mark. She then spent the night with Mark at their house. Her mother and father show up unexpectedly and she starts to panic and puts Mark in the closet. â€Å"I surprised myself – I didn’t care too much about his pain. I just heard the knocking getting louder and more urgent† (page 104, line 30-31). What worries Rita the most is upsetting her parents and she knows that they doesn’t like for her to be white. Therefor she quickly hides Mark because it  is her â€Å"white side† and she doesn’t wants to be a disappointment to her parents. She lets them in and they start to tell her about Mrs. Methi’s daughter, who has run away with a white man. But in reality they are using that story instead of telling her directly that they know about her and Mark. At one point her father goes into the kitchen to talk to her because he has always been the one to get the truth out of her. One thing he is telling her is: â€Å"Girls like that are left with fatherless children without an identity† (page 108, lines 7-8). He says this to scare her and tries indirectly to affect her not to stay with Mark. Rita doesn’t get these hints until they leave and says that she would like to introduce them to Mark. The story ends with a cliffhanger but you are still let with a feeling of what is going to happen. She will tell her parents that she is with Mark and that they have to respect that. By the look of what they have been telling Rita in the house they are not going to be taken it lightly. Because they are so traditional she is now a shame to the family. But you can tell that Rita is a strong woman, so she is going to go against her parent’s judgment and stay with Mark.