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Local Area Networks

 - Ethernet

Modern Ethernet implementations often look nothing like their historical counterparts. Where long runs of coaxial cable provided attachments for multiple stations in legacy Ethernet, modern Ethernet networks use twisted pair wiring or fibre optics to connect stations in a radial pattern. Where legacy Ethernet networks transmitted data at 10 megabits per second (Mbps), modern networks operate at 100 or 1,000 Mbps (1Ghz).

Perhaps the most striking advancement in contemporary Ethernet networks is the use of switched Ethernet. Switched networks replace the shared medium of legacy Ethernet with a dedicated segment for each station. These segments connect to a switch, which acts much like an Ethernet bridge, but can connect many of these single station segments. Some switches today can support hundreds of dedicated segments. Since the only devices on the segments are the switch and the end station, the switch picks up every transmission before it reaches another node. The switch then forwards the frame over the appropriate segment, just like a bridge, but since any segment contains only a single node, the frame only reaches the intended recipient. This allows many conversations to occur simultaneously on a switched network.

Ethernet switching gave rise to another advancement, full-duplex Ethernet. Full-duplex is a data communications term that refers to the ability to send and receive data at the same time. Legacy Ethernet is half-duplex, meaning information can move in only one direction at a time. In a totally switched network, nodes only communicate with the switch and never directly with each other. Switched networks also employ either twisted pair or fibre optic cabling, both of which use separate conductors for sending and receiving data. In this type of environment, Ethernet stations can forgo the collision detection process and transmit at will, since they are the only potential devices that can access the medium. This allows end stations to transmit to the switch at the same time that the switch transmits to them, achieving a collision-free environment.

 - NAT32

Many business users have private local area networks with only a single computer connected to the Internet.

NAT32 is a Microsoft Windows application which gives all computers on your private LANs direct Internet access. NAT32 runs only on the computer with the Internet connection and acts as an enhanced IP Router for the other computers on your private networks. The computer running NAT32 retains totally unmodified Internet access, and all applications on that computer will continue to run as before. On your other computers, most of your networking applications will require no reconfiguration, they simply pass all Internet packets to the NAT32 router, which forwards them to the Internet.

NAT32 supports Connection Sharing of Modems, ISDN Adapters, ADSL Adapters and Cable Modems. Each of your private computers is configured to use the NAT32 Router's unique private IP address as its DNS Server and Default Gateway. NAT32's built-in DHCP Server can configure the private computers automatically if you set them to "Obtain an IP address automatically" in Control Panel, Network, TCP/IP Properties.

NAT32 is available in two different versions: NAT32 Standard and NAT32 Enhanced. NAT32 Enhanced has a new, simplified user interface called the Quick Dialog. Toolbar Icons let you select commonly needed features  with a single mouse click. A list box displays the most important NAT32E Settings. To test and modify those settings, simply double-click the desired list box entry to access its configuration dialog box. The details in the Quick Dialog are updated dynamically, giving you instant feedback if a connection goes down, a Name Server has failed or any other important settings have changed. A Progress Bar shows the current throughput for each Internet adapter NAT32E is currently using.

NAT32E is the only package of its kind to offer a full-featured PPPoE Server Testbed for Windows 98/ME/2000/XP platforms. This feature works in conjunction with the RASPPPoE driver and allows tracing and debugging of PPPoE traffic. NAT32E is the only package of its kind to fully support multiple Internet Interfaces, multiple private LANs and multiple private LAN gateways. It surpasses Microsoft® Internet Connection Sharing in both performance and flexibility and is well-suited for use in large networks with complex private LAN topologies. NAT32E is now compatible with Windows ICS. Use ICS to share one Internet Connection and NAT32E to share other Internet Connections. All versions of NAT32 fully support the Windows Dial-Up Networking Server in TCP/IP mode

- Wireless Local Area Networks

A wireless local area network (WLAN) is a flexible data communications system implemented as an extension to, or as an alternative for, a wired LAN. Using radio frequency (RF) technology, wireless LANs transmit and receive data over the air, minimising the need for wired connections. Wireless networks enhance existing wired networks by providing convenient access to network resources for workers carrying portable computers and handheld devices (both in the office and in public facilities such as airports and hotels). A wireless network can also provide a cost-effective alternative to relocating physical Ethernet jacks in environments where facilities are moved or changed frequently. Successful deployment of an 802.11b network requires careful planning and network design. This process includes determining network applications, coverage requirements, number of users, client device types, and equipment selection. In addition, unlike wired  networks, environmental obstacles that can impede radio frequency (RF) signal transmissions must be carefully tested before implementing WLAN.  With wireless LANs, users can access shared information without looking for a place to plug in, and network managers can set up or augment networks without installing or moving wires. Wireless LANs offer the following productivity, convenience, and cost advantages over traditional wired networks:

Mobility: Wireless LAN systems can provide LAN users with access to real-time information anywhere in their organisation. This mobility supports productivity and service opportunities not possible with wired networks.

Installation Speed and Simplicity: Installing a wireless LAN system can be fast and easy and can eliminate the need to pull cable through walls and ceilings.

Installation Flexibility: Wireless technology allows the network to go where wire cannot go.

Reduced Cost-of-Ownership: While the initial investment required for wireless LAN hardware can be higher than the cost of wired LAN hardware, overall installation expenses and life-cycle costs can be significantly lower. Long-term cost benefits are greatest in dynamic environments requiring frequent moves and changes.

Scalability: Wireless LAN systems can be configured in a variety of topologies to meet the needs of specific applications and installations. Configurations are easily changed and range from peer-to-peer networks suitable for a small number of users to full infrastructure networks of thousands of users that enable roaming over a broad area.

Security: Because wireless technology has roots in military applications, security has long been a design criterion for wireless devices. Security provisions are typically built into wireless LANs, making them more secure than most wired LANs. It is extremely difficult for unintended receivers to listen in on wireless LAN traffic. Complex encryption techniques make it impossible for all but the most sophisticated to gain unauthorised access to network traffic. We provide a full range of services for wireless local area network environments - from scheduling a survey, to test, design, and implementation of full infrastructure network. Our experience in wireless point-to-point communications helps us to be one of the advanced companies in providing wireless services. For your needs the best wireless equipment on the market will be used, such as:

• Cisco Aironet Access Point
• Lucent Orinoco Access Point
• Apple AirPort Base Station
• Enterasys Networks RoamAbout Access Point


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