Found 1627 Articles for Computer Network

This article will help you to create IPtables rules that you can directly use for your daily or routine needs, These examples will act as basic templates for you to work on iptables with these rules which suit your specific requirement.Deleting the IPtables or Existing RulesBefore you start building new IPtables set of rules, you should clean up all the default rules, and existing rules. Use the IPtables flush command, below are some examples –#iptables --flush (or) # iptables --FDefault Policies ChainThe default policy is ACCEPT, change the policy to DROP for all the INPUT, FORWARD, OUTPUT.# iptables -P INPUT ... Read More

Both VPN and Proxy are used to connect to a remote system where one can access the host system from a remote location. However, VPNs are superior than Proxy servers because a VPN can protect your privacy and security by routing your traffic via a secure VPN server and encrypting it. A Proxy, on the other hand, just routes your traffic via a mediating server and it does not provide any additional security.Read through this article to find out more about VPN and Proxy and how they are different from each other.What is a Virtual Private Network (VPN)?A virtual private ... Read More

There are various application programs that we can use to access the resources of a remote machine. Telnet and SSH are the primary client server application programs that use remote terminal service which allows a user at one site to interact with a remote timesharing system at another site as if the user’s keyboard and a display is connected directly to the remote machine. Telnet and SSH both are Layer7 application layer protocols and both use TCP (Transmission Control Protocol) at the transport layer. In this article, we will discuss the important differences between SSH and Telnet. But before going ... Read More

Multitasking plays an important role in the context of defining the performance of a computer. Multitasking decides how processes are divided and performed by the CPU between different inputoutput subsystems. In order to process multiple tasks most efficiently, computer systems use various methods to schedule the tasks, speed up calculations and improve Web browsing among which Spooling and buffering are the primary methods. In this article, we will discuss the major differences between spooling and buffering. But before going into the differences, let's have a basic overview of spooling and buffering so that it will become easier to understand how ... Read More

QoS traffic scheduling is a scheduling methodology of network traffic based upon QoS (Quality of Service). Here, the frames or packets are mapped to internal forwarding queues based on its QoS information, which are then services according to a queuing scheme.Typically, multiple queues are present each with different priority levels. The scheduler decides the type of treatment to be given to the traffic in each queue. When traffic is available, the scheduler maps it to the appropriate queue. For example, video and voice traffic are kept is queued with higher priority than background traffic.Notable QoS Traffic Scheduling MethodsWeighted Round Robin ... Read More

Worldwide Interoperability for Microwave Access (WiMAX), is a wireless microwave technology based on the IEEE 802.16 standards. It was originally published in 2001 by WiMAX forum, the version which is now called fixed WiMAX. It is similar to Wi-Fi, though it provides higher data rates up to 1 Gbps even at distances of 30 miles.WiMAX forum defines WiMAX as – A standards-based technology enabling the delivery of last-mile wireless broadband access as an alternative to cable and DSL.Features of WiMAXWiMAX is a coalition of wireless industry based upon IEEE 802.16 standards.It aims for the advancement of broadband wireless access (BWA) ... Read More

IEEE 802.16 is a standard that defines Wireless Interoperability for Microwave Access (WiMAX), a wireless technology that delivers network services to the last mile of broadband access.The IEEE 802.11 standard that lays down the specifications of the wireless local area networks (WLAN) or Wi-Fi, that connects wireless devices within a limited area.The following chart gives a comparison between 802.16 and 802.11 −FeatureIEEE 802.16IEEE 802.11TechnologyDefines WIMAX.Defines WLANs or WiFi.Application AreaLast-mile of broadband wireless access.Limited area forming wireless LANs.Versions of the Standard802.16a, 802.16d, 802.16e, 802.16m etc.802.11a, 11b, 11g, 11n, 11ac, 11ad etc.Domain of UsageIt is used for a wide area mostly outdoors.It ... Read More

Dynamic Frequency Selection (DFS) is a technique used in IEEE 802.11 wireless networks or WiFi that permits devices to dynamically switch the operating frequency of transmission in order to avoid interference with other devices.FeaturesDFS is a legal mandate for all IEEE 802.11 devices which share 5 GHz radio spectrum with radar.DFS was adopted in IEEE 802.11h standard for wireless transmissions. It came up in 2003, when the wireless network started using 5 GHz band that is primarily used by radar systems.The objective of DFS is to prevent co-channel interference of signals between the primary user, i.e. radar systems, and the ... Read More

Wireless broadband (WiBB) a networking technology designed to impart highspeed Internet and data service through wireless networks. Wireless broadband may be delivered through wireless local area networks (WLANs) or wide area networks (WWANs).Similar to other wireless services, wireless broadband can be either fixed or mobile.Features of WiBBWiBB is similar to wired broadband service since they connect to an internet backbone, with the difference that they use radio waves instead of cables to connect to the last mile of the network.The range of most broadband wireless access (BWA) services varies around 50 km from the transmitting tower.Download speeds provided by some ... Read More

The Advanced Encryption Standard, or AES, is an encryption standard established in 2001 by the National Institute of Standards and Technology (NIST) of USA. It is implemented worldwide both in hardware and software to encrypt sensitive data. AES finds wide usage while transmitting data over computer networks, particularly in wireless networks.Features of AESAES is a subset of Rijndael block cipher.It is a successor of Data Encryption Standard (DES) and is stronger and faster than DES.It is a symmetric key symmetric block cipher.It operates on 128-bit (16 bytes) data.The cipher key may be of 128, 192 or 256 bits.All computations are ... Read More