In this post, we will understand the difference between backup and recovery.BackupIt refers to storing a copy of the original data in a separate memory location.It is basically a copy of data that is used to restore the original data in case of a data loss/damage.It is the replication of data.It just keeps one extra copy to ensure data is not lost forever.It helps in giving data protection.It makes the process of data recovery hassle free and easy.It is an affordable process.It is used in production environments.Example - SnapManager helps create a backup of data and everything else in the ... Read More

As we know in context of computer/system, the main key feature on which the whole performance get dependent is Memory. It is memory and its allocation which make the system to perform fast and efficient. Now on the basis of organizing of this memory in the system, we can distinguish between Simultaneous and Hierarchical Access Memory Organisations.Following are the important differences between Simultaneous and Hierarchical Access Memory Organisations.Sr. No.KeySimultaneous Access Memory OrganisationsHierarchical Access Memory Organisations1DefinitionSimultaneous Access Memory Organisations is the memory organizing technique in which CPU can interact with multiple memory levels at same time and gets data interaction. This ... Read More

Communication, in general, is the process of transferring data from a source to a destination by using any of the available modes such as audio, video, text or even signals, etc. This communication may be straightforward between one sender and one receiver or it may include multiple senders and receivers. On the basis of the number of senders and receivers involved, a communication can either be "Point-to-Point" or "Multi-point".Read through this article to find out more about these two forms of communication and how they differ from each other.What is Point-to-Point Communication?In telecommunications, a point-to-point connection is a communications link ... Read More

As we know that Cryptography comprises of two processes which are namely as encryption and decryption performed at sender and receiver end respectively. Basically Cryptography is practiced or implemented for doing secure communication between sender and receiver in the public environment in such a manner that other than these two parties no one could get or understand the message that is delivered.On the basis of type of encryption and decryption of the message we can distinguish between Classical and Quantum Cryptography as follows −Sr. No.KeyClassical CryptographyQuantum Cryptography1BasisIn Classical Cryptography encryption and decryption is done on the basis of mathematical computation.On ... Read More

Inverted Index and Forward Index are data structures used to search text in a document or set of documents.Inverted IndexInverted Index stores the words as index and document name(s) as mapped reference(s).Forward IndexForward Index stores the document name as index and word(s) as mapped reference(s).The following are some of the important differences between the Inverted Index and Forward Index.Sr. No.KeyInverted IndexForward Index1Mapping PatternInverted Index stores the words as index and document name(s) as mapped reference(s).Forward Index stores the document name as index and word(s) as mapped reference(s).2Index Building ProcessScan the document, prepare a list of unique words.Prepare a list of ... Read More

Top-Down Parsing and Bottom-Up Parsing are used for parsing a tree to reach the starting node of the tree. Both the parsing techniques are different from each other. The most basic difference between the two is that top-down parsing starts from top of the parse tree, while bottom-up parsing starts from the lowest level of the parse tree. Read this article to learn more about top-down parsing and bottom-up parsing and how these two parsing techniques are different from each other. What is Top-Down Parsing? Top-Down Parsing technique is a parsing technique which starts from the top level of the ... Read More

Both Substitution Cipher and Transposition Cipher are traditional techniques used in cryptography to encrypt a plaintext into ciphertext in order to prevent it from getting tampered. Read through this article to find out more about Substitution cipher and Transposition cipher and how they are different from each other.What is Substitution Cipher Technique?In the Substitution Cipher technique, each character is substituted with other character/number or other symbol. This technique changes the identity of a character but not its position in the string.A substitution cipher encrypts a text sequence by replacing letters or units of text with other letters or units of ... Read More

Steganography, or cover writing, is a method where a secret method is converted into fake looking message. This technique helps to keep a message secret. It is pretty difficult to use and understand. The structure of data remains unaltered in Steganography. It is used in text, audio, video or images. Cryptography, or secret writing, is a method where a secret method is converted in cipher text and sent to other person who then decrypt the cipher text into plain text. Cryptography can be classified as Symmetric key cryptography or Asymmetric key cryptography. Read through this article to find out more ... Read More

Many times we need to search for a particular string which may be present in multiple files. In this article we'll see which commands to use to find all the files that contains a particular string or Word.Using grepIt is a powerful regular expression search tool. At a basic level , it will match an input string with the list of files that contain that string.Below is the syntax and the example.grep 'string' directory-path/*.* #Example grep 'config' hadoop-2.6.5/etc/hadoop/*.*Running the above code gives us the following result −hadoop-2.6.5/etc/hadoop/capacity-scheduler.xml: hadoop-2.6.5/etc/hadoop/core-site.xml: hadoop-2.6.5/etc/hadoop/hadoop-policy.xml: hadoop-2.6.5/etc/hadoop/hdfs-site.xml: hadoop-2.6.5/etc/hadoop/httpfs-site.xml: hadoop-2.6.5/etc/hadoop/kms-acls.xml: hadoop-2.6.5/etc/hadoop/kms-site.xml: hadoop-2.6.5/etc/hadoop/mapred-site.xml.template: hadoop-2.6.5/etc/hadoop/ssl-client.xml.example: hadoop-2.6.5/etc/hadoop/ssl-server.xml.example: hadoop-2.6.5/etc/hadoop/yarn-site.xml:Using grep -rIn ... Read More

The hard disk in a computer is formatted with specific file system so that the operating system can read and write into it. For UNIX based systems we have various type of file systems. In this article we will see how to format a new partition in hard disk with ext4 file system.Available Filesystem typesFirst we see what are the different file systems available for the current operating system. The below command lists all those file systems.$ ls -1 /sbin/mkfs*Running the above code gives us the following result −/sbin/mkfs /sbin/mkfs.bfs /sbin/mkfs.cramfs /sbin/mkfs.ext2 /sbin/mkfs.ext3 /sbin/mkfs.ext4 /sbin/mkfs.ext4dev /sbin/mkfs.fat /sbin/mkfs.minix /sbin/mkfs.msdos /sbin/mkfs.ntfs /sbin/mkfs.vfatLook ... Read More