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Subnetting is the technique of partitioning a large network into smaller networks. On the other hand, the supernetting is the method used for combining the smaller ranges of addresses into larger space. Supernetting was devised to make the routing process more convenient. Additionally, it reduces the size of routing table information so that it could consume less space in the router’s memory. The well-defined method for the subnetting is FLSM and VLSM while for supernetting CIDR is used. Difference between Subnetting and Supernetting Subnetting is the technique of partitioning a large network into smaller networks. On the other hand, the supernetting is the method used for combining the smaller ranges of addresses into larger space. Supernetting was devised to make the routing process more convenient. Additionally, it reduces the size of routing table information so that it could consume less space in the router’s memory. The well-defined method for the subnetting is FLSM and VLS

“Go-Back-N Protocol and “Selective Repeat Protocol” are the sliding window protocols. The sliding window protocol is primarily an error control protocol, i.e. it is a method of error detection and error correction. The basic difference between go-back-n protocol and selective repeat protocol is that the “go-back-n protocol” retransmits all the frames that lie after the frame which is damaged or lost. The “selective repea t protocol” retransmits only that frame which is damaged or lost. Key Differences Between Go-Back-N and Selective Repeat Go-Back-N protocol is design to retransmit all the frames that are arrived after the damaged or a lost frame. On the other hand, Selective Repeat protocol retransmits only that frame that is damaged or lost. If the error rate is high i.e. more frames are being damaged and then retransmitting all the frames that arrived after a damaged frame waste the lots of bandwidth. On the other hand, selective repeat protocol re-transmits only damaged fra

The quick sort and merge sort algorithms are based on the divide and conquer algorithm which works in the quite similar way. The prior difference between the quick and merge sort is that in quick sort the pivot element is used for the sorting. On the other hand, merge sort does not use pivot element for performing the sorting. Both sorting techniques, quick sort and merge sort are built on the divide and conquer method in which the set of elements are parted and then combined after rearrangement. The quick sort usually requires more comparisons than merge sort for sorting a large set of elements. Key Differences Between Quick Sort and Merge Sort : In the merge sort , the array must be parted into just two halves (i.e. n/2). As against, in quick sort, there is no compulsion of dividing the list into equal elements. The worst case complexity of quick sort is O(n 2 ) as it takes a lot more comparisons in the worst condition. In contrast, merge sort have the same worst case and

The Process and Thread are the essentially correlated. The process is an execution of a program whereas thread is an execution of a program driven by the environment of a process. Another major point which differentiates process and thread is that processes are isolated with each other whereas threads share memory or resources with each other. Key Differences Between Process and Thread : All threads of a program are logically contained within a process. A process is heavy weighted, but a thread is light weighted. A program is an isolated execution unit whereas thread is not isolated and shares memory. A thread cannot have an individual existence; it is attached to a process. On the other hand, a process can exist individually. Each thread has its own stack, so if a thread dies its stack is reclaimed. In contrast, if a process dies, all threads die including the process. Conclusion: Processes are used to achieve execution of programs in concurrent and sequential manner.

Deadlock and Starvation both are the conditions where the processes requesting for a resource has been delayed for a long. Although deadlock and starvation both are different from each other in many aspects.  Deadlock  is a condition where no process proceeds for execution, and each waits for resources that have been acquired by the other processes. On the other hands, in  Starvation , process with high priorities continuously uses the resources preventing low priority process to acquire the resources. Key Differences Between Deadlock and Starvation: In a deadlock, none of the processes proceeds for execution, each process get blocked waiting for the resources acquired by the another process. On the other hand, starvation is a condition where the processes that possess higher priority is allowed to acquire the resources continuously by preventing the low priority processes to acquire resources resulting in indefinite blocking of low priority processes. Deadlock arises when four

The scheduling which takes place when a process switches from running state to ready state or from waiting state to ready state is called  Preemptive Scheduling . On the hands, the scheduling which takes place when a process terminates or switches from running to waiting for state this kind of CPU scheduling is called  Non-Preemptive Scheduling . The basic difference between preemptive and non-preemptive scheduling lies in their name itself. That is a Preemptive scheduling can be preempted; the processes can be scheduled. In Non-preemptive scheduling, the processes can not be scheduled. Key Differences Between Preemptive and Non-Preemptive Scheduling: The basic difference between preemptive and non-preemptive scheduling is that in preemptive scheduling the CPU is allocated to the processes for the  limited  time. While in Non-preemptive scheduling, the CPU is allocated to the process till it  terminates  or switches to  waiting state . The executing process in preemptive scheduli

Whenever a process is loaded or removed from the physical memory block, it creates a small hole in memory space which is called fragment. Due to fragmentation, the system fails in allocating the contiguous memory space to a process even though it have the requested amount of memory but, in a non-contiguous manner. The fragmentation is further classified into two categories Internal and External Fragmentation. Key Differences Between Internal and External fragmentation The basic reason behind the occurrences of internal and external fragmentation is that internal fragmentation occurs when memory is partitioned into  fixed-sized blocks  whereas external fragmentation occurs when memory is partitioned into  variable size blocks . When the memory block allotted to the process comes out to be slightly larger than requested memory, then the free space left in the allotted memory block causes internal fragmentation. On the other hands, when the process is removed from the memory it crea

The memory management in the operating system is an essential functionality, which allows the allocation of memory to the processes for execution and deallocates the memory when the process is no longer needed. If we talk about the basic differences between the paging and segmentation it is, a  page  is a fixed-sized block whereas, a  segment  is a variable-sized block. Key Differences Between Paging and Segmentation The basic difference between paging and segmentation is that a page is always of  fixed block size  whereas, a segment is of  variable size . Paging may lead to  internal fragmentation  as the page is of fixed block size, but it may happen that the process does not acquire the entire block size which will generate the internal fragment in memory. The segmentation may lead to  external fragmentation  as the memory is filled with the variable sized blocks. In paging the user only provides a  single integer  as the address which is divided by the hardware into a  page

Block Cipher and Stream Cipher are the methods used for converting the plain text into cipher text directly and belong to the family of symmetric key ciphers. The major difference between a block cipher and a stream cipher is that the block cipher encrypts and decrypts a block of the text at a time. On the other hand, stream cipher encrypts and decrypts the text by taking the one byte of the text at a time. Key Differences Between Block Cipher and Stream Cipher Block cipher technique involves encryption of one block of text at a time, i.e. singly. Similarly, decrypt the text by taking one block after another. In contrast, Stream cipher technique involves encryption and decryption of one byte of the text at a time. Block cipher uses both confusion and diffusion while stream cipher relies only on confusion. The usual size of the block could be 64 or 128 bits in the Block cipher. As against, 1 byte (8 bits) at a time is converted in the stream cipher. Block cipher uses  ECB (El

DES (Data Encryption Standard) and AES (Advanced Encryption Standard) both are the symmetric block cipher. AES was introduced to overcome the drawback of DES. As DES has a smaller key size which makes it less secure to overcome this triple DES was introduced but it turns out to be slower. Hence, later AES was introduced by the National Institute of Standard and Technology. The basic difference between DES and AES is that in  DES  plaintext block is divided into two halves before the main algorithm starts whereas, in  AES  the entire block is processed to obtain the ciphertext. Key Differences Between DES and AES. The basic difference between DES and AES is that the block in DES is divided into two halves before further processing whereas, in AES entire block is processed to obtain ciphertext. The DES algorithm works on the Feistel Cipher principle, and the AES algorithm works on substitution and permutation principle. The key size of DES is 56 bit which is comparatively smal

Ransomware:  is a type of  m alicious software  from cryptovirology  that threatens to publish the victim's data or perpetually block access to it unless a ransome  is paid.  While some simple ransomware may lock the system in a way which is not difficult for a knowledgeable person to reverse, more advanced malware uses a technique called cryptiviral exortion  , in which it encrypts  the victim's files, making them inaccessible, and demands a ransom payment to decrypt them. In a properly implemented cryptoviral extortion attack, recovering the files without the decryption key  is an  intractable   problem – and difficult to trace digital currencies   such as Ukash  and BitCoin  are used for the ransoms, making tracing and prosecuting the perpetrators difficult. Spyware   is software that aims to gather information about a person or organization without their knowledge, that may send such information to another entity without the consumer's consent, or that asserts

Torjan Horse: I n Computing, a Torjan Horse is a program that appears harmless but is in fact malicious. Torjan horse contains the malicious code when triggered causes the loss or the theft of data. Unlike the virus, it is not able to replicate  itself nor it can propagate without an end user assistance. This is why attacker must use social engineering tactics to trick the end user into executing the Torjan. Typically, malware programming is hidden into the innocent looking email attachment or free download. when user clicks on the email attachment or download  the free program the malware that is hidden is transferred into the users computing device  and carry out the task as designed by the attacker. some of them are : Bitfrost , Tiny Banker ,Fake AV Trojan, Magic Lantern ,Zeus. Computer Virus: C omputer Virus is a malicious code that replicate by copying itself to another program , computer boot sector or documents and change how a computer works. It works in two p