The most recent articles from IT Week

Review: Gigabit switch offers flexibility

Martin Courtney — 2008-01-15T00:00:00.000Z

Martin Courtney, IT Week, Tuesday 15 January 2008 at 00:00:00

D-Link’s Layer 3 Gigabit Ethernet switch provides room for LAN and WAN growth

D-Link's xStack DGS-3427 is a Layer 3 managed Ethernet switch aimed at companies looking to connect branch office LANs into a central network backbone, and who may require fibre-optic Gigabit or 10 Gigabit Ethernet uplink options to do it.

The unit features 24 auto-sensing 10/100/1000Mbit/s Ethernet ports, and up to 12 units totalling 288 Gigabit ports can be configured for a stack in a ring topology. Switches can also be configured as a virtual stack using standard network cabling. D-Link promises stacking in a star configuration to be available in a future firmware upgrade.

Alongside the 24 Gigabit ports, the switch features four small form factor ports that can be used to accommodate fibre-optic transceivers. These include 1000Base-LX, 1000Base-SX, 1000Base-LH and 1000Base-ZX transceivers, all of which are supplied by D-Link at an extra charge.

As well as these, the rear of the switch has three apertures able to accommodate single-port copper-based 10GbE XFP or 10GBase-CX4 modules for 10Gbit/s uplink bandwidth. To reinforce its suitability for mission-critical environments, D-Link has also included a module for a redundant power supply.

The 1U switch can be rack or surface mounted, but despite being designed for branch offices, the noisy fan makes it best suited for installation in a server room.

Also provided are serial and power cables, a quick installation guide and a driver CD containing a 254-page user manual in PDF format. This also holds a couple of add-in software modules for D-View 5.1, D-Link’s own network management suite, which has to be registered online before you can activate it, and HP’s OpenView.

We could not connect to the switch’s default IP address, but were quickly able to do so once we reassigned the IP address by using telnet to access the command line interface. Once this was done, it was just a case of typing the address into the browser and inputting the username and password to begin managing the switch. The Web Manager interface is basic but easy to use.

The DGS-3427 provides the option of configuring L2/L3/L4 multi-layer access control lists and 802.1x user authentication via Terminal Access Controller Access Control System (Tacacs+) and Remote Authentication Dial-In User Service (Radius) servers. Layer 3 IPv4/v6 static routing and IPv6 tunnelling capabilities can be configured to improve network performance and security, and D-Link has included an automated network security health check mechanism, though this works only in conjunction with the manufacturer’s NetDefend firewall software if installed.

The DGS-3427 provides extensive VLAN support, and quality of service parameters can be defined to provide transmission priority to converged applications.

Review : Plug-in solution for LAN-less offices

Dave Bailey — 2007-11-20T00:00:00.000Z

Dave Bailey, IT Week, Tuesday 20 November 2007 at 00:00:00

Motorola’s Powerline MU Gateway brings LAN connectivity to buildings via the mains

Motorola’s Powerline Multiple-Unit (MU) Gateway is designed to offer a quick and easy way of providing buildings with LAN connectivity over the mains electricity supply. Motorola is a member of the HomePlug Powerline Alliance, and the system works by converting Ethernet signals into the HomePlug protocol before injecting it directly into a building’s electrical system.

The gateway operates in the 4-21MHz spectrum and can be used in single-phase or three-phase electrical systems, with security being taken care of by the 56bit Data Encryption Standard (DES).

Raw Powerline data rates are currently 85Mbit/s and Motorola quotes typical user data transfer rates of about 8-12Mbit/s per gateway. The maximum transmission distance between Gateway and modem is 100 metres, and one Powerline MU Gateway can serve up to 50 users simultaneously.

Firms thinking of installing a system for LAN connectivity over mains power must have a site visit from Motorola to establish the layout of the electricity supply in the building. Installation also requires the co-operation of the firm’s maintenance contractor.

The system can be used in large single properties, multiple units and across enterprise campuses. Powerline MU products are designed to be used on low-voltage wiring, which in the UK means 230V and 50Hz AC.

The system can use two methods of injecting the signal into the mains: inductively coupled injection or capacitive injection. The inductive coupler consists of non-conductive ferrite rings that can be wrapped around the electric cables in the electricity distribution cabinet, with one coupler being used per electrical phase. The signal penetrates the cable’s insulation and enters the electric lines without touching the bare wire. Motorola says this is its preferred signal injection method for multi-metered buildings.

For our test we used capacitive injection to send signals between two modem s, a desktop PC and a laptop. We connected the gateway to a switch to get internet access, although users can configure the gateway’s onboard WAN link to be front-ended by a firewall before connection to a router.

The modems would normally be connected to a switch or wireless access point to give connectivity to desktop systems. This is the method we pursued while the gateway was connected to a switch and then through our four-port BT ADSL router. We also attached our 3Com AP7250 wireless access point to one of the modems, allowing us to access the internet wirelessly.

The Gateway is fairly simple and can be managed through a web-based interface or by using a dedicated management package called Prizm, which we installed on our Windows Server 2003 system.

Data transfer rates

We checked data transfer rates by measuring the time it took to send a 160MB file between the laptop and a shared drive on the desktop system. By placing the modem attached to our laptop at increasing distances from the gateway we could build up a picture of how transfer rates fared as the modem got further away from the gateway’s signal injection point.

The desktop was connected to one of the four 10/100Mbit/s LAN ports on the gateway. An initial measurement with the modem next to the gateway’s injection point gave a transfer rate of 10.9Mbit/s, while moving the laptop to a desk a few feet away resulted in a data transfer rate dropping to 3.6Mbit/s. We then plugged the laptop into a socket some 18 feet from the unit and recorded a rate of 1.2Mbit/s. We could not ascertain whether these varied results were down to the electrically hostile Labs environment or due to a non-optimal signal injection position.

To tackle situations where the transfer rate falls off rapidly, Motorola offers modem distribution units that act as repeaters to increase signal strengths. These units can service up to four modems.

Each Powerline modem has four LEDs that indicate whether the unit is receiving AC power, whether it can detect Powerline signals on the wires, whether it has established an Ethernet link to connected devices, and finally whether it has registered with the nearest Powerline gateway.

Managing the system by browsing to the gateway’s web page was straightforward. We could set network encryption keys, whether the gateway was to use DHCP and which authentication servers to use. We could also set up SNMP traps for problem condition alerts. It was easy to see which modems were currently up and running, and to get access to systems logs.

Review : Layer 2 switch gives Extreme value

Dave Bailey — 2007-11-19T00:00:00.000Z

Dave Bailey, IT Week, Monday 19 November 2007 at 00:00:00

Extreme’s Summit X150 switches offer a good range of features for an affordable price

Extreme Networks’ Summit X150 series of 10/100Mbit/s switches represent the vendor’s first foray into the low-end business market. The 1U, Layer 2 switches come in 24- or 48-port versions, with Power over Ethernet available as an option on both.

We reviewed the 24-port X150-24p model with IEEE 802.3af PoE giving 15.4W to all ports. X150 models can be upgraded with either an internal redundant power supply unit the EPS 160 or an external one the EPS-500 but there is no capacity to add 10 Gigabit Ethernet capability.

Besides its 10/100Mbit/s ports, the X150-24p has two auto negotiating 10/100/1000Base-T copper ports and two small form factor (SFP) Gigabit Ethernet optical ports. Both 10/100 and gigabit SFPs can be used with the X150. There is also a single 10/100Mbit/s out-of-band management port at the rear and an RS-232 console connection at the front.

For network management, users can choose from the ExtremeXOS command line interface (CLI), SNMP, or the browser-based ExtremeXOS ScreenPlay interface.

We set up the switch by connecting an RS-232 cable to our Elonex Piranha Pro notebook running Windows 2000 Professional and set the management virtual LAN (VLAN) to a 192.168.1.0 subnet address using the CLI. After this we could connect an RJ-45 cable to the management port at the rear of the X150-24p and use the ScreenPlay GUI to further configure the system. ScreenPlay is easy to navigate and users can also check environmental parameters, such as the temperature of the switch and the state of the fans.

We were able to create VLANs for traffic specific to our AirTight Networks Wi-Fi sensor network and another specifically to allow for voice over IP calls. We could also prioritise voice traffic by setting quality of service (QoS) at a higher level than for normal traffic. If more than 100Mbit/s of bandwidth is needed, users can also use 802.3ad link aggregation to combine up to eight ports on a single logical connection.

The X150 is a Layer 2 edge switch but it can also deal with some Layer 3 and 4 information, although it cannot perform IP routing using protocols like RIP or OSPF.

It also has a comprehensive feature set for a Layer 2 switch, with 802.1x, web or MAC-based authentication, protocol anomaly detection and denial of service protection.

Review : Gigabit switch offers controllable power

Dave Bailey — 2007-10-23T00:00:00.000Z

Dave Bailey, IT Week, Tuesday 23 October 2007 at 00:00:00

Nortel Networks’ 4548GT-PWR is a fully featured switch with impressive PoE capabilities

Nortel Networks’ 4548GT-PWR switch has 48 10/100/1000BaseTX RJ-45 connections with Power over Ethernet (PoE) and four shared small form factor gigabit ports.

In IT Week tests, initial setup entailed connecting an RS-232 cable to our Windows 2000 Professional system, firing up the onboard hyperterminal program and then providing network parameters to Nortel’s 4548GT-PWR setup utility. We could set the device and gateway IP addresses, as well as community strings for Simple Network Management Protocol (SNMP). We put the 4548GT-PWR on a 192.168.1.0 subnet and connected three AirTight Network sensors with Category 5 cables, which supplied power through the Gigabit Ethernet ports. We also connected one of AirTight’s SpectraGuard Enterprise appliances.

We could manage the 4548GT-PWR using either the command line interface, a web graphical user interface (GUI), or by installing Nortel’s Java Device Manager (JDM). The JDM has a versatile GUI that can display a real-time graphical representation of the front panel of the 4548GT-PWR switch. This meant that although we could see throughput trends by accessing the AirTight web GUI, we could also graph throughputs using Nortel’s JDM.

Nortel’s JDM can be installed on Windows 2000 or XP Professional systems, or on systems running Sun’s Solaris, Linux or HP-UX.

The 4548GT-PWR can generate 320W, delivering a maximum of 6.6W per port when all 48 ports are active. This can be increased to 15.4W per port through the addition of an optional 420W external power unit. We could control power to specific ports in 1W increments from a minimum of 3W to a maximum of 15.4W.

The system also allowed us to guarantee power to designated high-priority ports, and reduce power to low-priority ports. Another optional extra is Nortel’s Ethernet RPS 15 backup device, which can inject 320W into the 4548GT-PWR in the event of a mains failure.

The 4548GT-PWR is part of Nortel’s ERS 4500 Series switch family. Like its siblings, the 4548GT-PWR has a rear-mounted cascade port operating at 40Gbit/s bi-directionally, which allows firms to stack up to eight units giving 384 gigabit ports. There are extra gigabit uplinks through small form factor pluggable optical transceivers. All small form factors are supported except for the XFP 10Gbit/s version.

Standards support is comprehensive, with 802.1d, 802.1p prioritisation, 802.1x port access control, and 802.1w catered for, but the 4548GT-PWR’s routing protocol support is limited to the Internet Group Management Protocol (IGMP).

Review : Appliance keeps rogue systems at bay

Dave Bailey — 2007-10-17T00:00:00.000Z

Dave Bailey, IT Week, Wednesday 17 October 2007 at 00:00:00

Fortinet’s UTM offers a good range of security options, but configuration can be tricky

Fortinet’s FortiGate-224B is a security appliance for Windows systems that also acts as a Layer 2 switch or router. It has anti-virus, intrusion detection and prevention, anti-spam and web content filtering capabilities, and also supports IP security (IPsec) and Secure Sockets Layer (SSL) virtual private network (VPN) connections.

Our test model arrived at the labs in so-called trusted mode and it was simple to connect it to our BT ADSL router. The 224B has two 10/100Mbit/s WAN interfaces, giving firms redundant access to the internet, a RJ-45 management console port, two gigabit ports, and 24 10/100Mbit/s ports. The appliance can also be set up to act as a router.

The default IP address is 192.168.1.99, and initial setup was achieved by connecting a standard Windows XP Professional system with an IP address on the same subnet using one of the LAN ports. After connecting the device to our router, we set about configuring it to protect our Windows 2003 Server system and several client systems. We managed the 224B locally as well as remotely over a Secure Shell (SSH) connection and also by connecting to the appliance through a workstation using a LogMeIn Pro account.

Once the system was operating correctly we could back up its configuration into a separate folder on our management PC or onto a USB device. Saved configurations can also be encrypted and password protected for extra security.

We had a few problems configuring the appliance remotely, and at one point inadvertently managed to block off access to the appliance completely.

The interface is good, although the wealth of features makes it seem a little cluttered. Also, performance can suffer if too many Layer 7 functions, such as email inspection, are turned on.

The 224B has a clientless port-based security profile system. We used this to restrict network access to systems running Windows XP and specific third-party firewall and anti-virus packages. The 224B only supports Windows and so is not recommended for firms running a mix of operating systems.

Once the client profile is specified, it must be applied using the Strict Policy function, which can be set up to quarantine clients that are “out of policy”. Users who are denied access are directed to Fortinet’s remediation portal, which provides resources to help them meet the desired security requirements. Meanwhile, the Dynamic Policy option quarantines systems if a security event is detected after network access has been granted.

Security events detected by the device can also be forwarded to firms’ pre-defined syslog servers for event analysis or to Fortinet’s dedicated FortiAnalyzer appliance.

3Com SuperStack 3 4500PWR

Dave Bailey — 2006-03-07T00:00:00.000Z

Dave Bailey, IT Week, Tuesday 7 March 2006 at 00:00:00

A Layer 3 stackable switch providing controllable Power over Ethernet for converged networks

Launched in December, 3Com's SuperStack 3 4500 series of Layer 3 10/100Mbit/s stackable switches is aimed at firms wanting secure converged networks.

The 4500 range consists of 26- and 50-port versions with or without Power over Ethernet (PoE). They can be managed through a Cisco Internetwork Operating System (IOS)-like command line interface (CLI), or through a comprehensive web GUI, or via other 3Com network management software.

We accessed the CLI through an RJ-45 console port using an RJ-45/serial connector, and also connected to the web GUI and 3Com's Network Supervisor V5.1 running on a standard Windows 2000 desktop. For even more secure access we could connect using a KDE Secure Shell (KSSH) front-end client running Secure Shell (SSH) 2 on Suse Linux Professional 9.3. Simple Network Management Protocol (SNMP) version 3 is also supported.

The 4500PWR has 24 MDI/MDI-X auto-sensing 10/100Mbit/s ports. And for uplink connections to gigabit-speed network devices there are two user-configurable " dual personality" Gigabit Ethernet ports offering a choice of copper connectivity using 1000Base-T or fibre, 1000Base-X, using optional small form factor pluggable (SFP) transceiver modules. We had two 1000Base-T SFPs, which we used to uplink to our gigabit core switch.

Up to eight 4500 series switches can be stacked, which, using the 50-port models gives 384 10/100 ports, and all can be managed through a single IP address.

We could connect a variety of wireless access points and IP cameras to the 4500PWR, but companies wishing to connect IP phones to the switch are limited to models from 3Com, Cisco, Pingtel and Polycom. Network staff can access detailed information about PoE-connected devices and the specific ports the devices are connecting to, and can specify how much power the devices can draw.

The 4500PWR has a total of 300 Watts it can allocate to the PoE ports. The web GUI is the best option for IT staff to check how much power is free and how much power is being used by connected devices. For instance, our 3Com AP7250 access point was using an average of 6W, but we could specify the maximum power (in mW) that the device could draw.

In addition, protocols can be prioritised and filtered to give priority to time-sensitive applications such as voice over IP (VoIP).

For security the 4500 supports 802.1x network access combined with Radius authentication.

If extra security is needed for attached devices, Radius Authenticated Device Access (Rada) can be applied, which checks devices' Media Access Control (MAC) addresses.

Port-based access control lists (ACLs) can also be applied and the 4500PWR supports the recently announced 3Com Quarantining service to isolate suspicious network traffic.

3Com OfficeConnect Wireless 11g

Alan Stevens — 2004-03-02T12:39:50.000Z

Alan Stevens, IT Week, Tuesday 2 March 2004 at 12:39:50

A set of products giving teleworkers, small firms and branch offices everything needed to build a secure 802.11g wireless LAN

Products that are able to support all three currently implemented wireless LAN standards - 802.11a, 802.11b and 802.11g - may grab the headlines but few firms need the added complexity or expense that a multi-standard network entails. What many want is a straightforward, affordable solution like OfficeConnect Wireless 11g from 3Com, which can deliver a single high-speed wireless technology - 802.11g in this case.

The OfficeConnect family comprises a PC Card adapter, access point and wireless cable/DSL broadband gateway, suitable for deployment in small to medium-sized enterprises. Range is around 100m for all three products, with dynamic rate-shifting to improve poor reception and clear channel selection to find the least busy channel. Maximum data transfer rates are advertised at 54Mbit/s, but users should not expect anything faster than 22Mbit/s in practical usage.

All three products support WEP (Wired Equivalent Privacy) encryption for security plus the newer 256bit WPA (Wi-Fi Protected Access) technology. This combines the Temporal Key Integrity Protocol (TKIP) and 802.1x authentication to thwart eavesdroppers by periodically generating a unique encryption key for each client. This gives a higher level of protection than the fixed keys used by WEP.

The OfficeConnect Wireless 11g PC Card adapter is a Type II (3.3 volt), 32bit device featuring a robust antenna that stretches the full width of the card as well as link status and activity LEDs.

Drivers are supplied for use with Windows 98SE, ME, 2000 and XP. The 3Com Wireless Card Manager utility makes card setup simple, with the option of defining multiple profiles to reflect the different settings required for the networks with which the adapter will communicate.

Ad hoc (peer-to-peer) networking can be configured, but most companies will opt for a separate access point to support multiple users and connect to the wired LAN. The OfficeConnect Wireless 11g Access Point, a beige box about the size of a small network switch, fulfils this role.

Power comes from an external AC adapter, and there are two antennae at the back, plus a single Fast Ethernet port for LAN attachment. Administrators configure the device over the wired network using a browser. The access point can support 802.11g and 802.11b links and up to 128 concurrent user connections.

Wireless clients can connect to the internet via the access point and a separate router, although a small network might combine these using the OfficeConnect Wireless 11g Cable/DSL gateway. This is the same size and shape as the access point, with a similar external AC adapter and antennae, but it has a four-port Fast Ethernet switch for local connectivity and a separate WAN port to attach to an external cable or DSL modem.

The gateway can support up to 253 simultaneous users - 128 of whom can be wireless - and incorporates both an internet router and a stateful inspection firewall with VPN pass-through to protect local network users from denial of service (DoS) and other common attacks.

URL filtering is another useful option on the cable/DSL gateway, which, at just under £80 + VAT, is a good choice for both branch offices and teleworkers, plus users wanting to network PCs wirelessly and provide shared internet connectivity at home.

Price: PC Card £44.99 + VAT; Access Point £64.99 + VAT; Cable/DSL Gateway £79 + VAT

Contact: 3Com 01442 438 000

Netgear FS526T

Alan Stevens — 2003-11-24T18:37:05.000Z

Alan Stevens, IT Week, Monday 24 November 2003 at 18:37:05

This Fast Ethernet switch offers simple management facilities and Gigabit backplane support

Netgear's latest fast Ethernet switch, the FS526T, is a half-way house between simple unmanaged switches and those with full Simple Network Management Protocol (SNMP) support. An embedded web server provides the remote management interface, through which it is possible to both monitor activity and configure basic virtual LAN (VLAN), port trunking and quality-of-service (QoS) functions. Not as comprehensively as with a more fully featured managed switch, but sufficient for smaller networks and for less than £7 per port.

Like other Netgear switches the FS526T features a robust blue metal enclosure that, in this instance, can be rack-mounted using the brackets supplied if required. The AC supply is built in and there is an integrated cooling fan, although it is noisy enough to cause firms looking to deploy the switch in an open-plan office some concern.

The price does not merit fibre optic connectivity, and the UTP ports are all arranged at the front. There are 26 ports altogether, the bulk of which are 10/ 100Mbit/s with just two supporting Gigabit Ethernet, typically to connect to servers or act as uplinks to a Gigabit backbone.

All are auto-sensing and have "auto-uplink" support, which means you can connect to either end-point devices or other switches/hubs without the need for crossover cables.

Behind the ports is an Asic-based store-and-forward switching engine with an overall bandwidth of 8.8Gbit/s, and support for 4,000 MAC addresses per switch with 784kB of shared buffer memory. The five-year warranty is fairly standard but the power supply is only guaranteed for a miserly two years.

Out of the box deployment is easy, but administrators need to run a utility supplied on CD-ROM to enable the more advanced features. This finds the switch on the network, then opens a browser-based management tool, while the default IP address used by the management interface can be changed or assigned through DHCP. Password protection is available both for the interface and to limit access to specific network stations.

Each port on the FS526T can be configured independently for speed, flow control and QoS via a browser. The options are pretty basic, with flow control, for example, either enabled or disabled and QoS priority set to normal or high, but this makes setup very easy indeed.

The interface is also straightforward for network managers who want to aggregate ports together to form trunks for connection to other networks, or set up port-based or 802.1Q VLANs. Switch settings can be backed up and restored and there are facilities to collect traffic statistics, again on a per-port basis.

Compared with a proper managed switch, the FS526T is somewhat basic and has to be managed individually rather than with others from a central management console. But this will not really be an issue for smaller IT departments with only one or two switches to worry about. Nor will the fairly basic traffic monitoring and management facilities, although if the network grows, administrators may want to upgrade to proper SNMP management, support for which cannot be added to the FS526T.

Contact: Netgear 01344 39702

Price: £175 + VAT

Rose Electronics UltraConsole

Network IT Week staff — 2003-11-24T18:32:09.000Z

Network IT Week staff, IT Week, Monday 24 November 2003 at 18:32:09

A sensible solution for reducing server-rack clutter

KVM (keyboard, video and mouse) remote control switches are essential tools in rack-dense datacentres. So too are console servers. They provide remote access to devices such as Ethernet switches and routers via serial ports.

UltraConsole combines the two in one unit that can be expanded to remotely manage up to 1,000 servers or devices from one central station.

The rack-mountable base unit is just 1U high for the four-port and eight-port models and 2U for the 16-port version. Port capacity can be increased by fitting an expansion card and connecting other UltraConsole switches. Network managers can also connect to ordinary Rose UltraMatrix switches, which do not have the serial console capabilities.

Servers and other devices are attached using custom UltraCable leads.

These can be up to 30m in length, with cables available for the attachment of hardware and computers from Sun, along with devices using USB or serial interfaces.

Prices depend on type and length, a standard 2m PS/2 cable starting at £50 + VAT. Another cable is needed for the KVM station, effectively the keyboard, video screen and mouse that will be used to remotely manage devices attached to the UltraConsole.

Multiple KVM stations can be supported when other switches are connected together, and there is built-in security to prevent access by unauthorised users to specific ports. An on-screen menuing system, the Advanced Video Interface (AVI), makes it easy to select the port to access, with keyboard shortcuts also available.

By combining a serial console with a KVM switch, a network manager gets full access to everything in the datacentre rack. Firms could use software remote control alternatives and Telnet, but they only work when the network is up and the software required is loaded. A hardware solution such as UltraConsole provides full access regardless of the state of the attached devices, with power cycling management available as an add-on.

Contact Rose Electronics 01264 850 574

Price: £1,100 + VAT

Netgear HE102 access point

Dave Bailey, IT Week — 2003-02-14T09:54:14.000Z

Dave Bailey, IT Week, IT Week, Friday 14 February 2003 at 09:54:14

Netgear's 802.11a wireless LAN access point proved easy to set up

Released late last year, Netgear's HE102 802.11a wireless LAN (WLAN) access point supports data transmission speeds up to 21Mbit/s, according to IT Week Labs tests. The theoretical maximum for the IEEE 802.11a standard is 54Mbit/s.

The system is easy to set up and use. It also has a Turbo mode that boosts transmission rates to 72Mbit/s, but this is not supported in Europe.

We reviewed the HE102 running a DHCP server and also on a subnet linked to a 3Com Superstack 3 4250T switch. Data transfer tests involved desktop and notebook systems running Windows 2000 and XP. Only Windows systems are currently supported, and companies running Windows XP can either use the in-built support for wireless networks or Netgear's configuration utilities.

Wireless Equivalent Privacy (WEP) data encryption can be set to 64bit, 128bit or extended mode 152bit. MAC address filtering is available, but in configurations using multiple access points the MAC address of client 802.11a PC Cards has to be entered separately into each access point.

Roaming between access points on the same subnet is supported, providing all access points are configured with the same Extended Service Set ID (Essid).

The HE102 can be configured through a serial port, via the Web using the latest versions of Internet Explorer or Netscape Navigator, or by direct connection through a crossover cable to a desktop or notebook system.

The HE102 has two adjustable antennae, and three multifunction LEDs indicate power, Ethernet and wireless activity. A restore-to-factory-default reset button is situated next to the power jack, which takes its power from a 3.7A/3.3V power brick.

The HE102's configuration interface was easy to set up and use, and installation of the HA501 PC Card was also easy. To test data transfer rates between the two, we transmitted a 300MB .zip file from a desktop PC linked to the same switch as the access point. The maximum rate we achieved was 21Mbit/s, which is comparable to Intel's 802.11a access point reviewed last year.

Turning on WEP encryption slows down the data transfer rate, however, and Netgear recommends line-of-sight for access point placement.

Firms using wireless configurations with multiple access points should run surveys to find the best location for them, since we recorded significantly lower rates when walls and ceilings blocked the signal's path. Users can check signal strength and transmit/receive data transfer rates through the configuration utility, though it would be better to see units of Mbit/s rather than packets per second.

Turbo mode can theoretically provide data transfer rates up to 72Mbit/s if additional transmission channels are utilised. However, only channels in the 5.15GHz to 5.25GHz radio frequency waveband are licensed for use in the UK, so the check box for Turbo mode is disabled.

Due to European regulations, Dynamic Frequency Selection (DFS) and Transmit Power Control (TPC) are standard on this model, a fact that means that the ad-hoc mode cannot be used to set up peer-to-peer networks for transferring data between systems that only have PC Cards. Maximum allowable power output for the UK is currently 200mW in the permitted band, which also limits signal range.

Price: Access Point £233 + VAT; PC Card £115 + VAT

Contact: Netgear 01344 397021

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D-Link DWL-900AP+

Dave Bailey, IT Week — 2002-11-29T09:57:48.000Z

Dave Bailey, IT Week, IT Week, Friday 29 November 2002 at 09:57:48

D-Link's latest wireless access point offers souped-up 802.11b throughput, but only when linked to other D-Link products

D-Link's DWL-900AP+ wireless access point (AP) can increase 802.11b wireless LAN (WLAN) data transfer rates by about 20 percent when used with other D-Link products, such as the DWL-520+ PCI adapter and the DWL-659+ PC Card.

When installed as a wireless bridge with another 900AP+ device, data transfer rates can theoretically reach 11Mbit/s, according to D-Link. We could not reach this speed in IT Week Lab tests, however, though we did register a 7Mbit/s transfer rate between the PC/PCI cards and the access point - a 20 percent improvement in performance. The boost in throughput derives from an integral Texas Instruments chip which implements Packet Binary Convolutional Coding (PBCC), but can still communicate with standard 802.11b products when set to normal mode.

By implementing PBCC, along with Intersil's Complementary Code Keying-Orthogonal Frequency Division Multiplexing (CCK-OFDM), D-Link is anticipating the 802.11g specification, which is undergoing IEEE ratification. Both standards may be incorporated into the final 802.11g specification as optional modes.

We tested the access point by connecting it to a 3Com 4250T Fast Ethernet switch, installing the DWL-520+ PCI card in a standard desktop system and the DWL-650+ PC Card in a standard notebook PC, with both systems running Windows 2000.

Setting up the access point is simple and can be done through a JavaScript-enabled browser or D-Link's management tool, which also provides real-time indicators of signal strength, link quality and data transfer rate.

The test file was a 1GB .zip file, and the maximum transfer rates we obtained were 6.5Mbit/s from AP to PCI card; 7.0Mbit/s to the PC Card; and 6.8Mbit/s from PCI card to PC Card.

We also used a notebook PC equipped with a standard 802.11b Compaq W110 PC Card to transfer files. Transfer rates averaged about 5.0Mbit/s to the access point, 4.8Mbit/s to the PCI adapter, and 4.9Mbit/s to D-Link's PC Card. The D-Link card could also associate easily with our Compaq WL1510 enterprise access point. Enabling encryption resulted in slightly slower transfer rates.

The 900AP+ can operate in four modes: as an access point; as a wireless client, connected via a crossover cable to a PC; as an AP to-AP bridge; or as an AP-to-multi-point bridge.

To check the claim that throughput could almost double if D-Link products are used to create a bridged network, we set up a 900AP+ to bridge to another 900AP+. Using this setup we measured a maximum data transfer rate of 5Mbit/s between the two access points, nowhere near D-Link's claimed transfer rate of about 11Mbit/s.

Have your say: contact IT Week

Price: £119 + VAT

Contact: D-Link 020 8731 5556

Intel 802.11a access point

Dave Bailey — 2002-09-25T15:10:21.000Z

Dave Bailey, IT Week, Wednesday 25 September 2002 at 15:10:21

Intel's WSAP5000 802.11a access point can support 54Mbit/s wireless LAN data rates, but a licence is needed to use it

The WSAP5000 802.11a access point from Intel is one of the first 54Mbit/s wireless LAN (WLAN) devices available in the UK. It costs £290 +VAT for the access point and £116 + VAT for the PC Card.

Because both the card and access point transmit data signals in the 5.15GHz to 5.35GHz radio frequency spectrum, it is illegal to use them without a licence from the Radiocommunications Agency. Users pay £300 per site for a six-month permit.

We reviewed the WSAP5000 in two configurations: connected direct via a cross-over cable to a desktop system, and linked through a switch.

The access point has one RJ-45 connection and a socket for a power brick.

It also features a hard reset, which returns access-point parameters to factory default settings. We had one 802.11a PC Card adapter and updated the firmware for this to the latest available, V1.01.10. However, the WSAP5000 cannot yet be upgraded to give 802.11b back-compatibility.

The manual indicates the four channels that can be used in the UK, which are from 5.18GHz to 5.24GHz in increments of 0.02GHz. Other channels are available but the instructions warn that to set such channels is "an infringement of national law".

The access point is managed through a Web browser - IE 5.5, Netscape 4.78 or 5.x; the operating systems supported are Windows 98SE, Me, 2000 and XP. If the PC Card is fitted to a notebook, the system must be configured to maximum battery power when away from the mains or transfer rates will suffer. High performance and high power are not selected by default and we altered these settings to maximum before measuring data transfer rates.

We loaded the Netbench 7.01 benchmark onto a desktop system, and the client software onto a laptop fitted with the adapter. Full duplex mode is needed on both sides when data transfer rates are being measured. Rates ranged from 18.7Mbit/s to 20.9Mbit/s, with a mean response time from the access point of 25.5ms.

We also measured a straight transfer rate by dragging and dropping a 1GB file onto a mapped drive on the desktop system to which the access point was attached. Encrypting traffic with 64bit and 128bit WEP caused little change in throughput. A configurable aerial gives omni and half-circle-front radio frequency radiation patterns.

LEDs show if the system is ready, indicating 54Mbit/s transmissions and whether they are linked to a client. Slower 11Mbit/s 802.11b transmissions are also flagged.

A site survey is essential before fixing the access point, since the 5GHz band is more sensitive to obstruction than the 2.4GHz band used by 802.11b products.