What is Classless Inter-Domain Routing (CIDR) in Networking?
/ June 14, 2018

Understanding networking is a fundamental part of configuring complex environments on the internet. This has implications when trying to communicate between servers efficiently, developing secure network policies, and keeping your nodes organized. CIDR (Classless Inter-Domain Routing) was introduced in 1993 replacing the previous generation of IP address syntax – classful networks. CIDR allowed for more efficient use of IPv4 address space and prefix aggregation, known as route summarization or supernetting. Basic Overview of CIDR A system called Classless Inter-Domain Routing, or CIDR, was developed as an alternative to traditional subnetting. The idea is that we can add a specification in the IP address itself as to the number of significant bits that make up the routing or networking portion. Classless inter-domain routing (CIDR) is a set of Internet protocol (IP) standards that is used to create unique identifiers for networks and individual devices. The IP addresses allow particular information packets to be sent to specific computers. Shortly after the introduction of CIDR, technicians found it difficult to track and label IP addresses, so a notation system was developed to make the process more efficient and standardized. That system is known as CIDR notation. To illustrate the problems with the class…

What is Proxy Server in Networking?
/ June 12, 2018

A computer can act on the behalf of other computers to request content from the Internet or an intranet. Proxy Server is placed between a user’s machine and the Internet. It can act as a firewall to provide protection and as a cache area to speed up Web page display. Proxy server is a computer that sits between a client computer and the Internet, and provides indirect network services to a client. It may reside on the user’s local computer, or at various points between the user’s computer and destination servers on the Internet. A proxy server intercepts all client requests, and provides responses from its cache or forwards the request to the real server. A client computer is connected to the proxy server, which acknowledges client requests by providing the requested resource/data from either a specified server or the local cache memory. Client requests include files or any other resources available on various servers. Basic Overview of Proxy Server Basically proxy server plays an intermediary between the client computer and the server computer. The clients usually take the help of proxy server for requesting any files, any web pages or any other resources. The proxy server acts as an…

What is Network Time Protocol (NTP) in networking?
/ June 7, 2018

Network Time Protocol (NTP) is very important for modern networks. If the time across network devices is not accurate, this can have a direct impact on network security and network management, just to name two. The key to accurate time in the network is to have your devices receive the correct time from an atomic clock, and then synchronize this correct time across all of the devices. Network Time Protocol ensures this process is automated and secure. This article serves as your introduction to this critical network function. NTP is a protocol designed to synchronize the clocks of computers over a network. Network Time Protocol (NTP) provides a mechanism to synchronize time throughout the network. An NTP device will form an association with NTP devices closer to the time source. NTP devices use a special measurement, called a stratum, to determine how far they are away from the time source. Basic Overview of the NTP NTP stands for Network Time Protocol, and it is an Internet protocol used to synchronize the clocks of computers to sometime reference. NTP is an Internet standard protocol originally developed by Professor David L. Mills at the University of Delaware. The NTP system is based…

What is X.25 Protocol in Networking?
/ May 31, 2018

With the growth in corporate packet switching networks and an increasing awareness of the opportunities for data theft, therefore we focus on the need for data security in X.25 networks. X.25 was a standard suite of protocols used for packet-switched communications over a wide area network—a WAN. A protocol is an agreed-upon set of procedures and rules. Two devices that follow the same protocols can understand each other and exchange data. X.25 can be a cost-effective means of networking systems in a wide geographical area, compared to traditional dial-up (circuit switched) connections, or remote-bridged local area networks (LANs) connected by leased lines. It provides worldwide interconnection for international corporations. Basic Overview of X.25 Protocol X25 is developed by ITU-T and it is a packet switched wide area network. As shown in the figure below, it is a interface between DTE and DCE for operation on public data network in packet mode. DTE stands for Data Terminal Equipment and DCE stands for Data Circuit Terminating Equipment. X25 is an end to end protocol. User usually will not be aware of packets passing between these terminals. X.25 defines procedures and protocols needed to establish, maintain and terminate the connections. It also defines services…

What is Different Configuration in HDLC Protocol?
/ May 26, 2018

High-level Data Link Control (HDLC) is a bit-oriented link layer protocol. Its most prominent feature is that it can transmit any types of bit stream transparently. HDLC supports point-to-point link only and does not support point-to-multipoint link. HDLC supports neither IP address negotiation nor authentication. It uses keep-alive messages to check link status. HDLC can only be encapsulated on synchronous link. Currently, this protocol is applied on the Serial interface and POS interface. Configuration in HDLC HDLC also defines different configurations for the three types of stations. The word configuration refers to the relationship between the hardware devices on a link. Following are the three configurations defined by HDLC. Unbalanced Configuration Balanced Configuration Symmetrical Configuration Unbalanced Configuration: The unbalanced configuration in an HDLC link consists of a primary station and one or more secondary stations. The unbalanced condition arises because one station controls the other stations. In an unbalanced configuration, any of the following can be used: Full-Duplex or Half-Duplex operation Point to Point or Multi-point networks Figure 1: Unbalanced Configuration Balanced Configuration: The balanced configuration in an HDLC link consists of two or more combined stations. Each of the stations has equal and complimentary responsibility compared to each other….

What is Simple Network Management Protocol (SNMP) in Computer Networks?
/ May 24, 2018

SNMP stands for simple network management protocol. It is a way that servers can share information about their current state, and also a channel through which administer can modify pre-defined values. While the protocol itself is very simple, the structure of programs that implement SNMP can be very complex. SNMP is one of the widely accepted protocols to manage and monitor network elements. Most of the professional–grade network elements come with bundled SNMP agent. These agents have to be enabled and configured to communicate with the network management system (NMS). Simple Network Management Protocol (SNMP), an application layer protocol, facilitates the exchange of management information among network devices, such as nodes and routers. It comprises part of the TCP/IP suite. System administrators can remotely manage network performance, find and solve network problems, and plan for network growth by using SNMP. Basic Concepts SNMP is a protocol that is implemented on the application layer of the networking stack. The protocol was created as a way of gathering information from very different systems in a consistent manner. Although it can be used in connection to a diverse array of systems, the method of querying information and the paths to the relevant information…

What is Blowfish Algorithm in Cryptography?
/ May 23, 2018

In cryptographic circles, plaintext is the message we are trying to transmit. The process of encryption converts that plaintext message into ciphertext, and decryption converts the ciphertext back into plaintext. Encryption algorithms are technically classified in two broad categories- Symmetric key Cryptography and Asymmetric Key Cryptography. In symmetric type of Cryptography, the key that is used for encryption is same as the key used in decryption. Examples of various symmetric key algorithms are Data encryption standard (DES), Triple DES, Advanced Encryption Standard (AES) and Blowfish Encryption Algorithm. In Asymmetric Cryptography, two unique keys are used for encryption and decryption. One is public and the other one is private. Examples of various Asymmetric key algorithms are Elliptic-curve cryptography (ECC), Diffie–Hellman key exchange, Rivest-Shamir-Adleman (RSA), etc. Overview of blowfish Algorithm Blowfish is another algorithm designed by Bruce Schneier in 1993 to replace DES. This symmetric cipher splits messages into blocks of 64 bits and encrypts them individually. Blowfish can be found in software categories ranging from e-commerce platforms for securing payments to password management tools, where it used to protect passwords. It’s definitely one of the more flexible encryption methods available. Blowfish is a symmetric block cipher that can be used as…

What is Virtual private network and how it works
/ May 18, 2018

VPN literally stands for virtual private network. With a VPN, all your traffic is held inside a private, encrypted tunnel as it makes its way through the public internet. You don’t access the destination until after you’ve reached the end of the VPN tunnel. The root of why VPNs are popular is because they can be used to anonymize and encrypt internet traffic. Governments, ISPs, wireless network hackers and others can not only not see what’s inside a VPN but also usually not even be able to find out who is using it. Overview of VPN A virtual private network, or VPN, is an encrypted connection over the Internet from a device to a network. The encrypted connection helps ensure that sensitive data is safely transmitted. It prevents unauthorized people from eavesdropping on the traffic and allows the user to conduct work remotely.  VPN technology is widely used in corporate environments. A Virtual Private Network (VPN) is an entity where remote locations are connected over a shared provider environment. It establishes connectivity between a set of geographically dispersed endpoints in a network infrastructure. The endpoints of the VPN are connected using links and increasing demand on the performance of network connectivity…

What is Secure Shell Protocol in Computer Network?
/ May 9, 2018

As Internet access becomes increasingly inexpensive and available, it has become a viable replacement for traditional couriers, telephone, and fax, as well as remote dial-up access to a company’s internal computer resources. SSH, the Secure Shell could be a common software based approach to network security. It is a protocol that enables user to log into another computer over a network, to execute commands in a remote machine, and to maneuver files from one machine to a different. Overview of Secure Shell SSH or Secure Shell is a network communication protocol that enables two computers to communicate and share data. An inherent feature of SSH is that the communication between the two computers is encrypted meaning that it is suitable for use on insecure networks. Secure Shell is a protocol that provides authentication, encryption and data integrity to secure network communications. Implementations of Secure Shell offer the following capabilities: a secure command-shell, secure file transfer, and remote access to a variety of TCP/IP applications via a secure tunnel. Secure Shell client and server applications are widely available for most popular operating systems. SSH (Secure Shell) is a protocol for running secure network services over an insecure network. The protocol serves…

What is MD 5 Algorithm in Network Security?
/ May 6, 2018

Overview of MD5 Algorithm Hash algorithms are important components in many cryptographic applications and security protocol suites. MD5 which stands for Message Digest algorithm 5 is a widely used cryptographic hash function. The idea behind this algorithm is to take up a random data (text or binary) as an input and generate a fixed size “hash value” as the output. The input data can be of any size or length, but the output “hash value” size is always fixed. MD5 was designed by well-known cryptographer Ronald Rivest in 1991. In 2004, some serious flaws were found in MD5. The complete implications of these flaws has yet to be determined. The MD5 algorithm is a cryptographic algorithm that takes an input of arbitrary length and produces a message digest that is 128 bits long. The digest is sometimes also called the “hash” or “fingerprint” of the input. MD5 is used in many situations where a potentially long message needs to be processed and/or compared quickly. The most common application is the creation and verification of digital signatures. Properties of a Message-Digest Algorithm When people plan to design a message-digest algorithm, they try to make the algorithm satisfy the following properties: It…

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