What is X.25 Protocol in Networking and its Architecture ?
/ 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 Protocol 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…

What is Different Configuration in High-level Data Link Control (HDLC) Protocol?
/ May 26, 2018

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…

What is Simple Mail Transfer Protocol (SMTP)?
/ April 29, 2018

Simple Mail Transport Protocol is the most widely adopted protocol for e-mail delivery. Simple Mail Transport Protocol (SMTP) was originally designed for a smaller community of users which was assumed to be well behaved and trust worthy. As such no heed was paid towards incorporating security protocols in it. But with its growth, this trust was breached, owing to lack of adequate security mechanism in it. Email is emerging as the one of the most valuable service in internet today. Most of the internet systems use SMTP as a method to transfer mail from one user to another. Description about SMTP SMTP stands for Simple Mail Transfer Protocol. This protocol allows transmitting electronic mail over the Internet or any other network. The protocol itself is designed on a character basis. Thus the entire transfer of a mail can be exanimated by a human being without having to decode first the data. This is the reason why mails can be send without major problem using a simple Telnet application. The entire process of sending a mail is describe here using a Telnet application as example base. Most e-mail systems that send mail over the Internet use simple mail transfer protocol (SMTP)…

What is Dynamic Host Control Protocol (DHCP)
/ April 28, 2018

In recent years with the rapid development of the wireless internet and mobile communication systems, the use of notebook computers, PDAs and portable systems is gradually increasing and has become popular. And most of the users may want to access the internet from anywhere in the world. However, when these mobile hosts move from one network to another, users have to change system configuration, including host IP address, default gateway, and name servers. In order to support the automatic configuration changes on these hosts, several technologies such as dynamic host configuration mechanisms or mobility support in the IP layer have been developed. What is DHCP? The DHCP is an internet protocol that lets network administrators centrally manage and automate the assignment of IP addresses in an organization’s network. Without the DHCP, the IP address must be entered manually at each host in an organization and a new IP address must be entered each time a host moves to a new location on the network. DHCP refers to Dynamic Host Control Protocol. DHCP is responsible for dynamically assigning IP addresses to all the computers in a network immediately after the computer starts. DHCP (Server) is used to automatically allocate IP addresses…

What is Ad hoc On Demand Distance Vector (AODV) Routing Protocol
/ April 27, 2018

Routing is an important function in any network; it be wired or wireless. Routing is the act of moving information from a source to a destination in an internetwork. During this process, at least one intermediate node within the internetwork is encountered. Traditional wireless communication networks require a fixed infrastructure over which communication takes place. Therefore, considerable resources and effort are required to set up such networks, even before they can actually be used. Routing is the process of selecting paths in a network along which to send network traffic Overview of AODV In order to facilitate communication within the network, a routing protocol is used to discover routes between nodes. The primary goal of such an ad-hoc network routing protocol is correct and efficient route establishment between a pair of nodes so that messages may be delivered in a timely manner. Route construction should be done with a minimum of overhead and bandwidth consumption. An Ad-hoc routing protocol is a convention or standard that controls how nodes come to agree which way to route packets between computing devices in a MANET. AODV is a very simple, efficient, and effective routing protocol for Mobile Ad-hoc Networks which do not have…

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