Wireless Networking for Small Businesses, Branches and Home Offices

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1 Wireless Networking for Small Businesses, Branches and Home Offices Whether one believes in the Internet revolution or not, it is true that the Internet today has become an essential element in running day-to-day business. To get the most out of the Internet s capabilities, businesses need fast and affordable connections for nearly all users in an office. For small businesses and offices and home telecommuters, the challenges of deploying technologies to best leverage the Internet can be daunting. Fortunately, a number of new standards and solutions have emerged to make this much easier. Wireless technology has recently matured sufficiently to be a technology to consider for many business environments. With wireless networking being adopted by small businesses around the world, the ability to connect using wireless and wired technology simultaneously is a business tool worth having. This paper gives an overview of wireless networking technology and standards. It describes how to implement a wireless network, and includes details of the 3Com OfficeConnect Wireless Cable/DSL Gateway and 3Com 11Mbps Wireless LAN Access Point 2000.

2 Wireless Technologies In a pure wireless network, computers communicate with one another using radio signals. As no wires are needed, this makes networking extremely easy, especially if computers are distributed around an office. It also makes it a lot easier to move computers around. For example, a laptop with a wirelessnetwork card is completely portable. Wireless networks typically are never pure but rather tie into a wired network. To accomplish this, one or more devices must tie together the wired and wireless domains. In theory, there are different technologies that can be used to create a wireless network, with technologies varying in the distance or range a network can operate and the speed at which the network is expected to run. In practice, the computer industry today has settled on a single standard technology Wi-Fi as the way to connect enterprise and small business networks. Here are four technologies key wireless technologies that are often discussed: Wi-Fi or b Bluetooth IrDA HomeRF (SWAP) Wi-Fi (IEEE b) is an industry standard that enables high-speed wireless data transmissions, making it well suited for computer networking b networking has a maximum throughput of 11Mbps a very reasonable speed for small business and enterprise businesses alike. At connection time, actual speed is negotiated. If 11Mbps is not possible (due to distance, number of users, or signal quality), the highest speed is autonegotiated by two Wi-Fi enabled devices. If 11Mbps cannot be sustained, the connection will be tried next at 5.5Mbps, then at 2Mbps, and finally at 1Mbps. A Wi-Fi network works best with access points as this will dramatically increase the wireless range. An access point it a hardware device that acts as an intermediary between two PCs or workstations and their wireless Network Interface Cards. An access point used in a wireless network effectively doubles the range of a network. This increased range again adds to the usability of this technology. Almost all wireless products aimed at the small business are Wi-Fi b products.

3 Bluetooth is also a well-known industry standard. It is typically used for very short-range communications, not high-speed networking. Bluetooth is designed to network a PC, PDA, cell phone and printer, all within a short distance of each other. Today, some devices are available with bluetooth functionality built-in (such as the Ericsson T68 cellular telephone); for devices without built-in bluetooth wireless support, there are bluetooth interface cards for instance, the 3Com Wireless Bluetooth PC Card (3Com Part Number 3CRWB6096). Infrared is also a wireless technology. One standardized approach, IrDA (Infared Direct Access), operates using line-of-sight infrared signals for data communication. Although IrDA can operate at speeds of up to 4Mbps, the need for line-of-sight severely limits the usefulness of this technology. The range of this technology is also limited to around 1 metre, which makes it unusable as a business networking solution. SWAP (Shared Wireless Access Protocol) was a precursor of Wi-Fi, both being based on a more general standard IEEE SWAP has a maximum throughput of 1Mbps and is aimed more at home networks. It can also be difficult to integrate with a wired network. In most cases, SWAP networks are normally point-to-point, therefore there is no need for an access point. However the range of the technology is small, and limits the usability. A wireless receiver is required for a SWAP network. This could be a PCMCIA or PCI card (for laptop or desktop PC) or a USB adapter. The industry continues to work on standards to improve wireless networking. Much work focuses on increasing the speed and distance of wireless communication so it can be used in more enterprise business uses, particularly at the network core. All significant work leverages the base IEEE standard. Wi-Fi is a safe technology to implement for nearly all small business applications; it will not be made obsolete any time soon. How to implement a Wireless Network The two essential components of a wireless network are a wireless access point and wireless Network Interface Cards (NICs). The access point, as mentioned previously, acts as the intermediary between two communicating computers; it also serves to connect the wireless world to a wired network. The wireless NICs are placed in PCs and laptops that will use the wireless network and are configured to communicate with the central access point. Choosing the type of wireless access point The first step in building a wireless network is to choose which type of wireless access point device you need. There are two types products that provide wireless access point functionality. A dedicated wireless access point

4 A gateway with a built-in wireless access point These products offer different feature sets, and the choice of which one to use will depend on the network requirements.. A dedicated wireless access point will control the wireless portion of the network and allow communication between the wired and wireless portions. It will feature an Ethernet port to enable connection to the wired network. A gateway with a built-in access point connects between the wired network, wireless network and the Internet. It controls all traffic going to the Internet and can be configured to allow or block traffic depending on a users needs. Positioning a wireless access point Once the decision has been made on which type of device to use, the next step is to decide where the wireless network is to be situated. It should be positioned so all the devices using the wireless network are well within the range of the chosen device, or so all the common areas like conference rooms have coverage. The wireless access point should be positioned: Centrally to the computers that will be using the wireless network. This location should be as high as possible in the building to optimize wireless connections Conveniently for a connection to a wired network entry point, if this is desired. This may be as simple as locating the access point within wiring distance to a switch port. Conveniently for a connection to the cable or DSL modem that is used to connect to the Internet (when using a wireless gateway only) So that the front panel LEDs are easily viewed for at-a-glance network inspection. When setting up a wireless gateway, the antennae should b positioned so that they are at 90 degrees to each other (e.g. one vertical, one horizontal) to optimize the area supported by the gateway s access point. Configuring your wireless network Once all equipment is installed, the configuration of the wireless network should be a simple task. For the whole network to work, the configuration settings defined in the access point must be duplicated in every wireless NIC. At the access point or wireless gateway, a Service Area Name (or Service Set Identifier (SSID)) and a wireless channel are selected to uniquely define the wireless network.

5 Sometimes, a network may require multiple access points. In this case, giving multiple access points the same SSID will make them part of the same network and will allow roaming between access points. At the PC or workstation with the wireless NIC, the same Service Area Name must be entered. Most NIC's search the radio channels to locate the channel that matches the Service Area Name, so the channel only needs to be entered in the access point or gateway, not in the NIC. In a small business with one or a few access points, the choice of channel will make very little difference. You may wish to select a specific radio channel if this channel is already in use by a different wireless network, or if there is interference present from another local source. Finally, enable the security within the access point to ensure the safety of your wireless network. For more information on this please see the Improving Security in Wireless Networks white paper. This completes the set-up of your wireless network. Now, your wirelessenabled PCs and laptops should be communicating to each other. 3Com offers wireless products that a small business with little or no networking expertise can easily configure and maintain a wireless network. The OfficeConnect Wireless Cable/DSL Gateway will provide shared broadband access between a wired and wireless network. The Access Point 2000

6 The 3Com Wireless Solutions 3Com is your source for wireless solutions for small business, branches and home offices. 3Com offers a full set of products, from gateways and access points to Network Interface Cards. 3Com OfficeConnect Wireless Cable/DSL Gateway 3CRWE51196 The 3Com OfficeConnect Wireless Cable/DSL Gateway is an easy-to-install, high-quality device which offers small business and home office users secure, reliable shared Internet access over cable, DSL and other broadband access services, while providing a simple way to manage and protect a local wired and wireless network. The 3Com OfficeConnect Wireless Cable/DSL Gateway offers Network Address Translation (NAT) security coupled with hacker attack detection and prevention. This will hide the local network from the Internet dangers as well as protecting it from Denial of Service attacks. VPN protocols (PPTP & IPSec) can pass through the gateway to allow the set-up of secure tunnels. The 3Com OfficeConnect Wireless Cable/DSL Gateway incorporates an b wireless access point providing shared Internet Access between both a wired and a wireless network.

7 Feature Sharing an Internet connection between multiple PCs Network Address Translation (NAT) Denial of Service (DoS) Attack Prevention Built-in b access point VPN Pass-Thru (IPSec and PPTP) User-Definable Special Application support Virtual servers User access privileges Built-in 4-Port 10/100 switch DHCP server Web-based Interface Lifetime Warranty Benefit Significant cost savings. Security through hiding the private network. Added security by ensuring that hacker attacks are not able to bring down the network. Allows seamless integration between wired and wireless networks. Allows secure connection to a remote network via the Internet, resulting in cost savings. Allows the operation of applications that need multiple, dynamic ports to be open (e.g. NetMeeting, MSN Gaming Zone). More flexibility for network. Allow publicly accessible servers to exist on the private LAN. Specify different access rights (Allow and block services) on a per-user basis. Allows connection of up to 4 computers directly to the gateway. Allows file and resource sharing. Enables easy network addressing. Allows intuitive management of the device and network addressing. Peace of mind.

8 3Com 11Mbps Wireless LAN Access Point CRWE20096A The 3Com 11 Mbps Wireless LAN Access Point 2000 is an affordable and simple-to-install access point. It s a great choice for basic b wireless LAN extensions that won t strain the budget. An embedded HTTP web management server allows remote management of the wireless LAN segments in branch and remote offices for efficient operation and savings. Because it avoids the expense and complexity of running cables, this wireless LAN solution costs less than wired LANs. It s also a very attractive option for equipping a home office or small office with wireless access.

9 Feature Connects to both wired and wireless networks Wi-Fi Certified Web-based Interface DHCP Server 40 and 128-bit encryption of wireless connections Small Footprint Benefit Allows seamless integration between wired and wireless networks. Provides interoperability with other Wi-FI certified products. Allows intuitive management of the device and network addressing. Enables easy network addressing. Allows secure connection between wireless client and access point. Requires very little space. 3Com Corporation, Corporate Headquarters, 5400 Bayfront Plaza, Santa Clara, CA To learn more about 3Com solutions, visit 3Com Corporation is publicly traded on Nasdaq under the symbol COMS. The information contained in this document represents the current view of 3Com Corporation on the issues discussed as of the date of publication. Because 3Com must respond to changing market conditions, this paper should not be interpreted to be a commitment on the part of 3Com, and 3Com cannot guarantee the accuracy of any information presented after the date of publication. This document is for informational purposes only; 3Com makes no warranties, express or implied, in this document. Copyright Com Corporation. All rights reserved. 3Com is a registered trademark and the 3Com logo is a trademark of 3Com Corporation.