How Routers works

The evolution of the Internet is one of the biggest game changers in the way we interact with technology today. As we’ve moved from the highly primitive ARPANet to America Online to browsing and streaming from a highly sophisticated wireless network, it’s hard to imagine life without going online.

You can thank the router for that. Yes, that little box with all those ports that you plug into the wall is actually the magical gateway for all of your devices to connect simultaneously to the Internet. Without it, you wouldn’t be able to click through your beloved GIFs of cats, stream Netflix or even connect to Google. Have you ever wondered how it really works? The anatomy of a router may surprise you — especially since it hasn’t changed much in the four decades of its existence.

The Hardware

Needless to say, the first system that functioned the same as a router — ARPANET’s "gateway" — was a massive machine that looked more like a refrigerator than an integral part to building and sustaining an internetwork of computers. Now, the typical home router can be picked up in one hand. Today’s most common routers work on just a few elements to efficiently translate your home's cable or DSL into a wireless or ethernet connection: a computer processor, RAM and flash memory, and ethernet ports. The few materials needed to make a working router means that computer-savvy folks can actually make routers out of an old computer.

What routers have an abundance of are reliable ports through which to feed the Internet connection. All routers have a WAN port, the cabled connection that connects the router to your cable or DSL. Then, there’s a multitude of LAN ports — local area network connections that allow you to wire everything, from your Xbox to your DVR, to the Internet. Looking for the magical wireless device? That’s usually the antenna flanking the modem, operated often at radio frequencies of both 2.4 Ghz and 5 Ghz to accommodate all devices without interference (thus the term “dual-band” router).

Activating a router usually takes little more than plugging all the necessary cables and powering it all up, but configuration can be done through the router’s available dashboard. In fact, you can log into your router by plugging in your IP (the number assigned to your Internet connection, usually beginning with "192.168") into your browser and logging into the system. However, different routers have different online dashboards, so check your user manual.

How It Runs

The way a router runs is fairly straightforward, since the system has become incredibly efficient over time. By taking in the cable or DSL information through a WAN connection, the router directs the information flowing through to ensure that all of the data is transmitted to the various devices connected to the Internet at any given time. The router is able to do that by individually assigning local ISPs to every computer, and simultaneously handling each system as a separate avenue to the Internet.

In addition to translating data connections and routing, the router is also the technology responsible for your firewall. As a hardware-based network security device, it’s the router that works with your computer’s software security protocols to prevent unsolicited Internet traffic — which could contain malware or other hacking technologies. Think of your router as the first line of defense in your firewall, throwing out any unwanted noise that doesn’t look like it’s assigned to any computer in the network. This keeps your computer safe, meaning you’ll be able to happily surf online securely.

It’s also worth noting that while routers don’t necessarily differ on how they obtain, transmit and output data, not all routers are equal. This is particularly relevant when looking at wireless routers, which have become ubiquitous for their ease and access. Wireless routers operate on two separate protocols, 802.11g and 802.11n (also known as G or N). Newer models can handle the faster wireless speeds that an N-enabled router can provide, but if your computer has an older wireless card, then you’ll have to stick with a G router. N-enabled routers also have greater ranges than G-enabled routers, so if you find yourself discouraged with how far your Wi-Fi travels, check your router and consider switching standards.

No matter what your router’s capabilities, this all adds up to one thing: Internet for everyone!

How It Makes Internet

The way a router actually communicates with a DSL or Cable modem to provide Internet is an interesting concept that can be explained with a few abstract principles.

First, it’s important to note that every piece of information that the Internet has is actually called a “packet.” When you log onto a web page, for example, your computer sends out a packet of data and receives a packet in return that loads the information you request. This is actually a series of communication protocols between “nodes,” or specific endpoints by which the information travels.

Routers have a key role in transmitting these packets, serving as a sort of switchboard operator for every packet that you send and receive. They actually communicate to each other across the wider IP system to ensure the data is taken and returned to proper nodes (say, from your computer to Google’s servers and back). In this context, the router is not only your translator but also your director, parsing all of your data to call up that cat picture you desperately wanted to see.

Without the router, we’d all be living in the analog ages. In short, there are very few things more necessary to the Internet than that little box gathering dust in a guest room or behind your television, so make sure to thank it when you fall into your next Internet binge.

An Overview Of Smart Power Grid

The present electric grids use the technology of 1970’s. But with the advancement in various concepts of power generation, problems associated with power outages and thefts, and also due to increase in demand, we require a modernized grid to avail all the needs of customers even in the situations of hype, which can be called a “smart grid”.

The smart grid performs various functions such that it increases grid stability, reliability, efficiency and ultimately reduces line losses.

Also the smart grids are designed to allow the two-way processing of electricity from consumers that have distributed generation. Various technologies like sensing and measurement, usage of advanced components are to be used for successful functioning of the grid. In this paper, smart grid, its functions, technologies used in smart grids are discussed.

Introduction to Electric Grid

The electric grid generally refers to all or the smart grid, in a nutshell, is a way to transmit and distribute electricity by electronic means. The electric grid delivers electricity from points of generation to consumers. The electricity delivery network functions via two primary networks: the transmission system and the distribution system. The transmission systems deliver electricity from power plants to distribution substations, while distribution systems deliver electricity from distribution substations to consumers.

The grid also encompasses myriads of local area networks that use distributed energy resources to several loads and/or to meet specific application requirements for remote power, municipal or district power, premium power, and critical loads protection.

Introduction to Smart Grid

Smart grid lacks a standard definition, but enters on the use of advanced of technology to increase the reliability and efficiency of the grid, from transmission to distribution. The Smart Grid is a vision of a better electricity delivery infrastructure.

In addition to being outdated, power plants and transmission lines are aging, meaning they have difficulty handling current electricity needs, while demand may not be reduced any time, but it can still be increasing continuously. One solution could be to add more power lines, but the aging system would still be overwhelmed.

So instead of a quick fix, a more reliable, permanent solution is needed. Perhaps the most fundamental aspect of transitioning to a smarter electricity system is the smart meter.

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Why Modernization of Electric Grid is required?

The major driving forces to modernize current power grids can be divided in four, general categories:

• Increasing reliability, efficiency and safety of the power grid.
• Enabling decentralized power generation so homes can be both an energy client and supplier (provide consumers with interactive tool to manage energy usage).
• Flexibility of power consumption at the client’s side to allow supplier selection (enables distributed generation, solar, wind, and biomass).
• Increase GDP by creating more new, green collar energy jobs related to renewable energy industry manufacturing, plug-in electric vehicles, solar panel, and wind turbine generation, energy conservation and construction.

Smart grid delivery

Smart Grid Functions

The integrated system of the smart grid has two scopes.

One scope is transmission monitoring and reliability and includes the following capabilities:

• Real time monitoring of grid conditions.
• Improved automated diagnosis of grid disturbances, and better aids for the operators who must respond to grid problems.
• Automated responses to grid failure that will isolate disturbed zones and prevent or limit cascading blackouts that can spread over a wide area.
• “Plug and play” ability to connect new generating plants to the grid, reducing the need for the time consuming interconnection studies and physical upgrades.
• The automatic restoration of power would be accomplished by a combination of sensors, computer analysis and advanced substation components, as well as by the ability to reroute power to outage locations.
• Enhancing ability to manage large amounts of solar and wind power.

The second scope is consumer energy management:

• At a minimum, the ability to signal homeowners and businesses that power is expensive and/or tight in supply. This can be done, via special indicators or through web browsers or personal computer software. The expectation is that the customer will respond by reducing its power demand.
• The next level of implementation would allow the utility to automatically reduce the consumer’s electricity consumption when power is expensive or scarce. This would be managed through the link between the smart meters and customer’s equipment or appliances.
• The smart grid system would automatically detect distribution line failures, identify the specific failed equipment, and help determine the optimal plans for dispatching crews to restore service. The smart grid would automatically attempt to isolate failures to prevent local blackouts to spread over that area.
• The smart grid would make it easier to install distributed generation such as rooftop solar panels, and to allow “net metering”, a rate making approach that allows operators of distributed generators to sell surplus power to utilities. The smart grid would also manage the connection of millions of plug-in hybrid electric vehicles into the power system.

Technology- Initial Focus

Smart Grids rely on information technology advancements across telecommunications and operations. Utilities apply these technologies both to grid operations – transmission and distribution wires and associated equipment and to the customer site-meters, customer owned energy technology equipment and appliances, and home area networks (HANs).

Wires

High temperature superconductor (HTS) wire enables power transmission and distribution cables with three to five times the capacity of conventional underground AC cables and up to ten times the capacity of DC cables. Fault current management capability when using Fault Blocker cable systems.

Wires-focused Smart Grid projects commonly involve:

• One of the components to smart grid would be the replacement of the aging power lineswith high-temperature superconducting lines.
• The new wires could be installed underground to avoid cluttering up the already congested cityscapes.
• New telecommunications and operational (sense and control) technologies: These improve delivery performance and resilience.
• New sensor and control technologies. These, when combined with distributed intelligence, make it possible to report and resolve grid issues in real time (self healing).
• Transmission and distribution intelligent electronic devices. These alert operators, automatically respond to problems, and integrate generation from renewable resources.

Sensing and Measurement

Smart Grid - Advanced Metering Infrastructure (AMI)

Core duties are evaluating congestion and grid stability, monitoring equipment health, energy theft prevention, and control strategies support. Technologies include smart meters, sensing systems, advanced switches and cables, digital protective relays etc… In all these, smart meters play a vital role.

In Smart Metering, an Advanced Metering Infrastructure (AMI) of interval meters and two-way communications systems serves as a gateway for utility/customer interaction. Smart Metering has the potential to reduce both customer and utility costs.

If you take a look at your current electricity meter, you will see that it is very mechanical, humming along blindly, waiting to be read by a technician, to determine the amount of electricity used in a given month, at the end of which you receive a bill. A smart meter utilizes what is known as real-time monitoring (RTM). A display lets the consumer know how much electricity is used and even when it is less expensive to use it.

Advanced Components

Innovations in superconductivity, fault tolerance, storage, power electronics, and diagnostics components are changing fundamental abilities and characteristics of grids.

Technologies within these broad R&D categories include: flexible alternating current transmission system devices, high voltage direct current, first and second generation superconducting wire, high temperature superconducting cable, distributed energy generation and storage devices, composite conductors, and “intelligent” appliances.

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Renewable Energy and the Smart Grid

Renewable Energy and the Smart Grid

The smart grid can be seen as an alternative energy source, certainly a change from the current way of doing things. In addition to rerouting electricity, the smart grid would be able to fill in the gaps of these alternative energy power sources. One way this could be accomplished, surprisingly enough, is with another alternative energy technology – the electric car, specifically, the plug-in electric hybrid (PHEV).

This would work through the concept of energy storage, in the case of the PHEV, specifically referred to as V2G or vehicle to grid. This use of alternative energy sources, like wind and solar reduces the nation’s dependence on foreign oil and helps keep pollution from car exhaust and power plants to a minimum.

Other Technologies

Integrated communications will allow for real-time control, information and data exchange to optimize system reliability, asset utilization, and security.

Conclusion

The major source of energy for human beings is electricity. Without electricity, no technology or science could have been possibly developed. But there are many problems associated with effective functioning of the electric grids which cause a serious loss of power and may even create severe scarcity in future. Also, the latest advancements in generation of electricity from renewable sources also require a means for effective utilization.

So, keeping in view of these, for better performance of the grid, smart grids should be developed all over the world So that we have a more transparent, reliable system that allows consumers to save money and utility companies to more accurately control electricity.

Thus Smart Grid technology paves way for increased utilization of green power.

USB (Universal Serial Bus): An Overview

While Communication in USB we consider three parts-

1.       a) Host which can be a Computer / PC/ laptops

2.       b) USB cable and connector

3.       c) Peripheral devices eg. Keyboards, mouse, audio player etc

USB systems consist of a personal computer (PC) known as host and multiple peripheral devices like mouse, keyboard, and audio system. The host itself contains two components, the host controller and the root hub. A host controller is a hardware component that is contained in a host computer. The Host controller converts the data in the language understandable to the OPERATING SYSTEM and also manages communication on the bus. The USB host controller has an embedded hub called the root hub. A hub is a common connection point that allows multiple devices to connect in the network. A hub contains multiple ports. The root hub connects the host controller(s) to the peripheral device and acts as the first interface layer to the USB in a system. The ports that are visible at the system's back panel are the ports of the root hub.  These ports are part of the root hub and in turn can be connected to external hub thereby increasing the number of USB devices which can be connected to host. An external hub can be used to extend the connections to the maximum of 127 devices.

Whenever a USB device is connected or disconnected it is first detected at the root hub which in turns passes information to the host controller. USB is a half duplex protocol where all data is passed via a two wire interface called D+ (D plus) and D- (D minus).

The host is responsible for the following tasks:

1.       1.Detect attachment and removal of USB devices

2.       2.Provide and manage power to attached devices

3.       3.Monitor activity on the bus and initiate the process of enumeration

4.       4.Manage data flow between host and devices.

               

When we discuss data transfer across the USB we always use the vantage point of the host for reference. For example, if there is an IN transfer that means the host is going to receive the data. An OUT transfer means the host is going to transmit data

USB cable and connectors

From an outer overview, USB has two components: cables and connectors. These connectors connect devices to a host. A USB cable consists of multiple components that are shielded by an insulating jacket. Underneath the jacket is an outer shield that contains a copper braid. Inside the outer shield are multiple wires: a copper drain wire which is a twisted pair of cable, a VBUS wire (red) and a ground wire (black). An inner shield made of aluminum contains a twisted pair of data wires.

There is a D+ wire (green) and a D- wire (white). In full-speed and high-speed devices, the maximum cable length is 5-meters. To increase the distance between the host and a device, you must use a series of hubs and 5-meter cables. While USB extension cables exist in the market, using them to exceed 5 meters is against the USB specification. Low-speed devices have slightly different specifications. Their cable length is limited to 3 meters and low-speed cables are not required to be a twisted pair as USB Twisted Pair Data Wires. The voltage bus gives a constant 4.40 v – 5.25v supply to all devices and the data lines supplies up to 3.3v. The reason for using the differential D+ and D- signal is for rejecting common-mode noise. If noise becomes coupled into the cable, it will normally be present on all wires in the cable. With the use of a differential amplifier in the USB hardware internal to the host and device, the common mode noise can be rejected.

Now we move ahead and learn more about the connectors. The figure below shows the various types of connectors.

There are many different types of USB ports and connectors available. The upstream connection always uses a Type A port and connector, while the device uses Type B ports and connectors. Initially, the USB specification included only the larger Type A and Type B connectors for devices but later included the Mini and Micro connections. These Mini and Micro connectors were initially developed for USB On-the-Go which is a USB specification that allows devices that would normally act as slaves to become hosts but later they were adopted in devices as they had smaller size as compared to type B.

1.       Type A- It is used for connecting the cable to the host device also known as upstream end. They are flat in shape and have four connections in line.

2.       Type B- It is used to connect cable to peripheral device and also known as downstream end. They are square in shape and have two connections on both sides of centre.

Micro A and Micro B type connector’s description table.