Classful Vs Classless Address

Hello friends in this post i am again going to tell you some more interesting concepts of networking.In this post i am going to tell you what is the difference between classfull and classless address.

Classful addressing:In the classful addressing system all the IP addresses that are available are divided into the five classes A,B,C,D and E, in which class A,B and C address are frequently used because class D is for Multicast and is rarely used and class E is reserved and is not currently used.Each of the IP address belongs to a particular class that’s why they are classful addresses.Earlier this addressing system did not have any name,but when classless addressing system came into existence then it is named as Classful addressing system.The main disadvantage of classful addressing is that it limited the flexibility and number of addresses that can be assigned to any device.One of the major disadvantage of classful addressing is that it does not send subnet information but it will send the complete network address. The router will supply its own subnet mask based on its locally configured subnets. As long as you have the same subnet mask and the network is contiguous, you can use subnets of a classful network address.
Classless Addressing:Classless addressing system is also known as CIDR(Classless Inter-Domain Routing).Classless addressing is a way to allocate and specify the Internet addresses used in inter-domain routing more flexibly than with the original system of Internet Protocol (IP) address classes.What happened in classful addressing is that if any company needs more than 254 host machines but far fewer than the 65,533 host addresses then the only option for the company is to take the class B address.Now suppose company needs only 1000 IP addresses for its host computers then in this (65533-1000=64533) IP addresses get wasted.For this reason, the Internet was, until the arrival of CIDR, running out of address space much more quickly than necessary. CIDR effectively solved the problem by providing a new and more flexible way to specify network addresses in routers.A CIDR network address looks like this:

192.30.250.00/15

The “192.30.250.00″ is the network address itself and the “15″ says that the first 15 bits are the network part of the address, leaving the last 17 bits for specific host addresses.One more advantage of classless addressing is that classless protocol sends subnet information. This allows you to create discontiguous networks with any given classful network address.

DHCP Server

Hello friends in this post i am giving answer to one of the most common question from the field of networking,that is how an IP address is assigned to any computer or any device like switch,hub,bridge.

DHCP is the only responsible to assign IP address to any device.Dynamic Host Configuration Protocol (DHCP) is a network protocol that enables a server to automatically assign an IP address to an individual computer’s TCP/IP stack software. DHCP assigns a number dynamically from a defined range of numbers configured for a given network.Today you found almost all wireless access points, many wired Ethernet routers, and computers running Internet Connection Sharing have built-in DHCP servers.Due to this reason DHCP servers are mainly preffered for the small networks in comparison to large networks.DHCP assigns a TCP/IP address when a system is started. Typically, it works like this:

1. A user turns on a computer with a DHCP client.

2. The client computer sends a broadcast request (called a DISCOVER or DHCPDISCOVER), looking for a DHCP server to answer.

3. The router directs the DISCOVER packet to the correct DHCP server.

4. The server receives the DISCOVER packet. Based on availability and usage policies set on the server, the server determines an appropriate address (if any) to give to the client. The server then temporarily reserves that address for the client and sends back to the client an OFFER (or DHCPOFFER) packet, with that address information. The server also configures the client’s DNS servers, WINS servers, NTP servers, and sometimes other services as well.

5. The client sends a REQUEST (or DHCPREQUEST) packet, letting the server know that it intends to use the address.

6. The server sends an ACK (or DHCPACK) packet, confirming that the client has a been given a lease on the address for a server-specified period of time.

When we assign IP address statically to any computer then there is always a probability that two computers are configured with the same IP address. This creates a conflict that results in loss of service. Using DHCP to dynamically assign IP addresses minimizes these conflicts.

Repeater Vs Hub Vs Switch

As all we know various types of devices like repeaters,hub, routers, switch are used very frequently in the setup of any computer network.Here in this post we see all these devices one by one.

Repeater: A repeater is an electronic device that is used to receive a signal and after receiving, it transmit signal to the higher level so that it can move to long distance without any destruction in its value.In other words we can also say that repeater is a device that is designed to overcome signal attenuation means to recover signal degradation.All repeaters has two ports one for receiving the signal and other for its transmission.Repeaters can be used for carrying electrical signals in the form of copper wire or to carry light in the form of fiber optics.It is a layer 1 device that means Physical layer device.

Hub: In simple words we can say that a hub is a multi port repeater.It means it allows multiple machines to connect to the same network, by broadcasting traffic to all of its ports.The most practical implication of this is that only one device can send data at a time, otherwise a collision occurs. Hubs implement a collision detection multiple access method to detect when two machines attempt to send data at the same time. A hub supports broadcasting of any signal.It is also layer 1 device.

Switch:In general switch is very much different from the repeater and the hub , both of them works on IP address while the switch works on the MAC address. A switch works by keeping track of which MAC addresses are attached to each port. It inspects traffic and only sends it to the port that the destination device is on (based on the destination MAC address). A switch had a finite amount of memory in which it can store MAC addresses, smaller switches such as ones intended for desktop use have less memory then larger ones that may form part of an enterprise networks backbone. When a switches memory becomes full of active MAC addresses it will often revert to functioning like a hub and broadcast traffic to all ports.A switch is a layer 2 device(Data link Layer).

Fastest DVD Writer

As all we computer users are aware of what a DVD writer do its main task to read data from DVD and write data to DVD. The comparison factor that is used to compare various DVD writers is their speed performance. Now Samsung is going to launch industry’s fastest DVD writer the new Super-WriteMaster SH-S223 which offers a powerful over-speed performance feature enabling consumers to burn data at high speeds, even on low speed media.

This is the first and only company in India that makes this product first. The main facility of this DVD writer is over-speed recording, users can write at 22X speeds on 16X media and 12X speeds on 8X media. As lower speed media is more cost-effective, users can save money while burning discs at faster speeds. Now with the help of this writer you can get blazing recording speeds across a gamut of different data media types including: 22X DVD±R recording, 12X DVD-RAM recording, 16X DVD+R Dual Layer recording, 12X DVD-R Dual Layer recording, 8X DVD+RW recording and 6X DVD-RW recording. This writer also provides you the facility of burn 4.7GB on a DVD±R disc in approximately 4 minutes and 26 seconds, a 6 percent increase in speed compared to a 20X DVD writer.

It also takes less than 12 minutes to burn 4.7GB in DVD-RAM format, which is a 30 percent increase in speed over a 20X DVD drive. This DVD writer easily supports the SATA interface, the dominant interface for pc’s. In addition to SAT[4] (Speed Adjustment Technology), TAC[5](Tilt Actuator Compensation) and Double OPC[6] (Optimum Power Control) it includes all the features of all the previous DVD writers.

Indian version of Youtube

As all we know every internet user is aware of the what the Google is and the various products of Google like Orkut, Google earth, Gmail, Youtube and many more. Here I am going to told you something about the world’s most visited website for online videos i.e youtube.com. Now youtube going to take the Indian version that means its Indian version is going to be launched in form of youtube.co.in which promotes an entirely local experience highlighting and featuring the content and functionality most desired by Indian users.

As all we know what Youtube is, the most popular online video community that allows people to discover, watch and share originally created content, announced the launch of its local Indian site.YouTube India features a localized homepage and search functions, allowing users to create and share videos, discover the most popular and relevant videos in India, and connect with other Indian and global users. Steve Chen the cofounder of Youtube is very excited about the launching the indian version of youtube.

They said its a new experience to bring a local version of YouTube to India considering the passion of users here for music and entertainment. In addition to all the international features some new local features are also added to this new version such as promoted videos, featured videos, and homepage promotions, localised user interface and help center. In addition to this, site also tries to facilitate connections among the large Indian NRI community. In India, YouTube has already signed partnerships with Eros Entertainment, Rajshri Films, IIFA, Ministry of Tourism, IIT Delhi, NDTV, UTV, Zoom TV, India TV and Krishcricket, to name a few, and will continue to work with a range of partners, across a range of genres, to bring Indian content to more people in new ways.

Hard disks in danger

From the title you think that what nonsense i am saying, but it is true. Now it is assumed in the various harddisk manufacturing industries like Kingston, Transcend etc that within the next few years hard disks are completely replaced by their next version that is SSDs that means Solid state drives. As flashed based memories, which are only limited to RAM, but USB storage devices and MP3 players evolved into a strong competitor for HDDs. The most significant development in this field was made by Samsung in May 2006, with the announcement of world’s first notebook PC, featuring a 32 GB NAND Flash based Solidstate disk(SSD), instead of traditional HDD. The main reasons behind that why SSDs take over the HDDs are form factor, speed, boot delay, power consumption, ruggedness and many more. Regarding power consumption SSDs consume only 5 percent of what HDDs devour. According to Samsung press release, SSDs read 300 percent faster(53 MBps) and write 150 percent quicker(28 MBps) then normal hard drives. Also HDDs cannot resolve the issue of boot delay(time that PC takes to start the operating system). The Microsoft Windows XP operating system will boot up 25-50 percent faster on n SSD compared to other drives claims Samsung. One more drawback of HDDs is that no matter how well they packed , HDDs are vulnerable to temperature, magnetic fields, humidity and physical impact whereas SSD are almost immune to them.

As all we know the thing that had some advantage also had some disadvantage ya i am talking about some drawbacks of SSDs the major one is its pricing, SSDs are much expensive as compared to HDDs - while HDDs offer storage at the rate of approx $1 per GB, but SSDs cost it bout $90 per GB. Some other drawbacks of SSDs are its reliabilityand storage capacity.

InfraRed Communication

As all we know what are the Infrared radiations, these are the radiations that are not visible from naked eyes, we can feel only these rays by their heating effect. More about infrared rays we can say that in daily life the heat that we received from the sun is the form of Infra red radiation. As all we know in the electromagnetic spectrum infrared radiations lies between microwaves and visible light,hence it can be used as a source of communication. As, here I going to tell u how infrared technology used incommunication. For infra red communication a photoled transmitter and a photodiode receptor is required. In Infrared communication the LED transmitter transmits the infrared signal as bursts of non-visible light. At the receiver end a photo-diode or a photo receptor detects and captures the light pulses,which are then proceed to retrieve the information they contain. In this way the information between the source and the target is transferred.The source and target can be mobile phones, laptops and any other thing that supports wireless communication. The main advantage of Infrared communication is that the power requirement for it is very low,hence it is best suitable for laptops,telephones etc.The circuitiry cost for it is also low.As the information transferred through infrared communication is highly secure because the data flow between the source and the target is unidirectional, means directionality of the infrared beam ensures that isn’t leaked or move to nearby devices as it’s transmitted.With having advantage, it also had some disadvantages like for data transmission between the source and target they must be directly aligned means both of them able to see each other. One of the major disadvantage of Infrared communication is that it is of short range in nature means it can not work when the source and target are at large distance from each other. The information transmitted through IR communication is easily affected by obstacles like peoples, walls etc, if they exists in the way of line of transmission, hence complete data is not received. The IR communication is also effected by environmental condition like weather, sunlight, rain, pollution etc. From all these points it is clear that IR communication is not a suitable method of wireless communication. Today, there are many technologies exists that are much better than IR like Bluetooth, Wi-fi etc.

“Funda of GPS”

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Hello friends,in this blog i want to give you some information regarding GPS(Global Positioning System).Actually,GPS is a technology which is used to find the location of its user.In the begining it intended only for the military purpose,but in the begining of 1980 it is available for the civilian use.GPS technology was developed by the Department of Defense of U.S. government.In technical words we can say that GPS is a fully functional Global Navigation Satellite System(GNSS) which is a network of 24 satellites placed in earth’s orbit.GPS is totally envirnoment or condition independent.It can works in any weather ,anywhere in the world and 24 hours a day.Actually GPS satellite works due to the centripretal force between GPS satellite and earth due to which it revolves around the earth twice in a day in very precise orbit and transmit signal information to earth. At earth GPS receiver receives these signal and uses triangulation to calculate user’s exact location.GPS is launched because to figure out where you are and where you’re going is probably one of oldest pastimes.The user’s location is calculated such that,the time difference between the transmitter send the signal and the receiver received the signal is calculated,and then with the help of other satellites the receiver can determine the user’s position and display it on the unit’s electronic map.In this way the position of any body can be calculated.Since,the era of GPS is started and in the next few years GPS will be at its top.

the 45nm effect

Hello friends this is my first blog ,in this blog i want to give you some information regarding “the 45nm effect” in chips.I hope it will be beneficial to you if you go through it. As all we know chips are the most important circuitry part of processors and processor speed is also depends on the size of the chips.In recent years chip making technology has been moved from 90nm to 65nm,but today it moved up to 45nm.The worlds largest processor making company Intel is shrinking chip sizes like never before.Intel has invested $1.5 billion in this project.Intel’s 45nm chip is believed to be smaller,faster,and more power efficient than all its predecessors. The “45nm effect” implies that by using nano technology size of the chips can be reduced up to 45nm. Hence, in order to reduce the chip size we have to reduce the transistor size,but as the transistor get thinner,electrical leakage takes place in the transistors.Hence while shrinking the size of the silicon-di-oxide gate dielectric,transistor gate leakage was one of the most difficult technical challenges that industry faced. To get rid of this problem,Intel has developed a hafnium-based material with the high k property (where k is the dielectric constant of the material),which helps deliver transistors with very low leakage current and high performance.Reducing power leakage and improving performance are the most important features of Intel project.The company’s most advanced manufacturing technology today is 65nm,which went into commercial production last year.In the current stage Intel has about fifteen 45nm product design in various stages of development.The resulting chips that are formed after “45 nm” technology will have 820 millions transistors to put in for parallel computing,energy management and graphics.Today market is still waiting for applications of this 45nm chip.The chips that are produced on 45nm technology will be faster ,consume less energy,contain more transistor and be cheaper to mass produce.All of this results in better PC,laptop and server processor speed,while reducing the amount of power leakage from transistors and hence overall efficiency is increased.In today’s server environment people want to consolidate.This is an opportunity for software developers across the globe to implement parallelism in their applications.But this is not the limit,very soon we see microprocessors that use up to 32nanometere chips from this industry.The future of smaller and more intelligent chips,according to the International Technology Roadmap for Semiconductors or ITRS(http://www.irts.net/reports.html),will be 32nm,22nm and then 16nm technology.

“The era of tera”

As all we know this is the age of science. In this scientific age computers played an important role in everyone’s life.A few years ago we thinked that if any computer executed thousands instruction per second then it is sufficient for any task,but as the requirement increases it is required to execute millions of instructions per second for that dual core and quad core processors are launched but these were hot topics only for a meanwhile.As the demand for computing power increases,the industry is moving towards “massively multi core technology”,in this technology such types of processors are required that can execute trillions of instructions per second.Hence in this order to achieve these task “teraflop” processors are launched.The performance of first teraflop computer is not as per requirements,there are some drawbacks associated with it,like it occupies a great space(more than 180 squares meters) and consumed 500 kilowatts of electricity and was powered by nearly 10,000 Pentium pro processors.In 2007, Intel achieved the same performance on a multi-core chip not bigger than a finger nail and consuming only 62 watts of power.On its launching its official stated that whenever in future,if there is need for this huge computing power ,then the end products will definitely come.The company revealed the artificial intelligence,instant video communications,photo realistic games,multimedia data mining could become everyday realities.The company also demonstrated a computer based on the 80-core chip running a scientific calculation at speeds above 1 trillion mathematical calculations per second.This level of performance is equivalent to that world’s fastest supercomputer of a decade ago.As all we knows performance is not directly related to the numbers of cores in a processor because after a certain level it starts diminishing.
As from all these points it is clear that “tera scale”computing has a bright future.If the world requires this high amount of computing power in future,”the era of tera” will definitely become a reality.