Optical fiber

Fiber Optic Networking

Networking is a wide ranging and loosely defined area in the industry. With all broadband and MSO applications using a network structure to deliver its signal, networking applications have a significant contribution in virtually every area. The defining difference is networking focused on the conduit and method of delivering a signal or content, rather than creation, switching, or termination.

With the increasing bandwidth requirements associated with broadband services, service providers and network operators are expanding and extending fiber optics further down line to accommodate present and future requirements. This network extension and expansion requires multiple fiber optic connectivity products in a myriad of forms. Trunk cables, distribution cables, high-density interconnect cables, and standard patch cords are just a few of the many types of products. Timbercon manufactures reliable fiber optic networking cables to support these networking applications.

One wireless router can allow multiple devices to connect to the Internet.

WiFi has a lot of advantages. Wireless networks are easy to set up and inexpensive. They're also unobtrusive -- unless you're on the lookout for a place to use your laptop, you may not even notice when you're in a hotspot. In this article, we'll look at the technology that allows information to travel over the air. We'll also review what it takes to create a wireless network in your home.

First, let's go over a few WiFi basics.

What Is WiFi?

What's in a name? You may be wondering why people refer to WiFi as 802.11 networking. The 802.11 designation comes from the IEEE. The IEEE sets standards for a range of technological protocols, and it uses a numbering system to classify these standards.

A wireless network uses radio waves, just like cell phones, televisions and radios do. In fact, communication across a wireless network is a lot like two-way radio communication. Here's what happens:

1. A computer's wireless adapter translates data into a radio signal and transmits it using an antenna.
2. A wireless router receives the signal and decodes it. The router sends the information to the Internet using a physical, wired Ethernet connection.

The process also works in reverse, with the router receiving information from the Internet, translating it into a radio signal and sending it to the computer's wireless adapter.

The radios used for WiFi communication are very similar to the radios used for walkie-talkies, cell phones and other devices. They can transmit and receive radio waves, and they can convert 1s and 0s into radio waves and convert the radio waves back into 1s and 0s. But WiFi radios have a few notable differences from other radios:

• They transmit at frequencies of 2.4 GHz or 5 GHz. This frequency is considerably higher than the frequencies used for cell phones, walkie-talkies and televisions. The higher frequency allows the signal to carry more data.
• They use 802.11 networking standards, which come in several flavors:
  • 802.11a transmits at 5 GHz and can move up to 54 megabits of data per second. It also uses orthogonal frequency-division multiplexing (OFDM), a more efficient coding technique that splits that radio signal into several sub-signals before they reach a receiver. This greatly reduces interference.
    
  • 802.11b is the slowest and least expensive standard. For a while, its cost made it popular, but now it's becoming less common as faster standards become less expensive. 802.11b transmits in the 2.4 GHz frequency band of the radio spectrum. It can handle up to 11 megabits of data per second, and it uses complementary code keying (CCK) modulation to improve speeds.
  • 802.11g transmits at 2.4 GHz like 802.11b, but it's a lot faster -- it can handle up to 54 megabits of data per second. 802.11g is faster because it uses the same OFDM coding as 802.11a.
  • 802.11n is the newest standard that is widely available. This standard significantly improves speed and range. For instance, although 802.11g theoretically moves 54 megabits of data per second, it only achieves real-world speeds of about 24 megabits of data per second because of network congestion. 802.11n, however, reportedly can achieve speeds as high as 140 megabits per second. The standard is currently in draft form -- the Institute of Electrical and Electronics Engineers (IEEE) plans to formally ratify 802.11n by the end of 2009.
• Other 802.11 standards focus on specific applications of wireless networks, like wide area networks (WANs) inside vehicles or technology that lets you move from one wireless network to another seamlessly.
• WiFi radios can transmit on any of three frequency bands. Or, they can "frequency hop" rapidly between the different bands. Frequency hopping helps reduce interference and lets multiple devices use the same wireless connection simultaneously.

WiFi Hotspots

If you want to take advantage of public WiFi hotspots or start a wireless network in your home, the first thing you'll need to do is make sure your computer has the right gear. Most new laptops and many new desktop computers come with built-in wireless transmitters. If your laptop doesn't, you can buy a wireless adapter that plugs into the PC card slot or USB port. Desktop computers can use USB adapters, or you can buy an adapter that plugs into the PCI slot inside the computer's case. Many of these adapters can use more than one 802.11 standard.

VPN (Virtual Private Network)

What is Virtual Private Network

VPN (Virtual Private Network)

Learn how to setup vpn, step by step instructions, how virtual private network works, windows configurations, and hardware and software requirement in the virtual private network. A virtual private network is a private network that uses public network (Internet) and maintains privacy and security procedures through encryption and other security procedure. VPN’s provides an alternative dedicated private network connection for the offices and companies.

PPPT provides a secure 128bit encrypted connection from the local computer to the VPN server. In VPN, not only the data is encrypted but the source and destination network address is also encrypted.
VPN uses internet as a medium to connect to the remote networks and sites and allows virtual connections.

Virtual Private Nework is an alternative method to connecting the office network or a LAN. Internet is a public domain and anyone with a computer, a phone line, modem and internet service can access it.

passwords, firewalls and other security procedures. VPN may be composed of a number of servers and sites.

The most common Virtual Private Nework is a remote-access VPN, which creates a secure tunnel from your computer and your company’s server.

In some cases you don’t even need to have internet access but you only need a computer, telephone line, modem and software, which network administrator might have installed on your computer or you will be provided with the instructions that how to configure PPTP.

After successfully configuring the PPTP, you will be able to dial the company’s server and access it by creating a VPN. In Virtual Private Nework, remote computers act as they are in the same and secure local network.
There are a number of advantages and disadvantages of the VPN connections

computer network diagrams

Networking

A useful procedure in network analysis is to simplify the network by reducing the number of components. This can be done by replacing the actual components with other notional components that have the same effect. A particular technique might directly reduce the number of components, for instance by combining impedances in series. On the other hand it might merely change the form in to one in which the components can be reduced in a later operation. For instance, one might transform a voltage generator into a current generator using Norton's theorem in order to be able to later combine the internal resistance of the generator with a parallel impedance load.

A resistive circuit is a circuit containing only resistors, ideal current sources, and ideal voltage sources. If the sources are constant (DC) sources, the result is a DC circuit. The analysis of a circuit refers to the process of solving for the voltages and currents present in the circuit. The solution principles outlined here also apply to phasor analysis of AC circuits.

Two circuits are said to be equivalent with respect to a pair of terminals if the voltage across the terminals and current through the terminals for one network have the same relationship as the voltage and current at the terminals of the other network.

If V₂ = V₁ implies I₂ = I₁ for all (real) values of V₁, then with respect to terminals ab and xy, circuit 1 and circuit 2 are equivalent.

The above is a sufficient definition for a one-port network. For more than one port, then it must be defined that the currents and voltages between all pairs of corresponding ports must bear the same relationship. For instance, star and delta networks are effectively three port networks and hence require three simultaneous equations to fully specify their equivalence.