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• Holiday Buyer's Guide 2006, Part 2: Networking

  Netgear RangeMax 240 Wireless Router + 4-port... (9 offers) Online shop Price See more products What? You haven't finished your holiday shopping yet? Well, in case you've been considering a networking-related gift, there are many products that are sure to please your giftee. This guide to networking gifts is based on hands-on experience with products reviewed throughout the year, and links are included to the related reviews and articles for your further exploration. You'll also find some tips on what not to buy, a bit unusual for a gift guide, perhaps, but equally important. You all know the drill and why you're here, so let's just get right to it. Wireless Networking Wi-Fi continues its march toward ubiquity despite crowded airwaves, flaky performance, over-hyped products and generally high buyer dissatifaction. But if you're determined to try to free yourself or a loved one from his or her cabled shackles, we have a few things to suggest. First, stay away from any products using draft 802.11n technology. Despite all the hype to the contrary, this standard is far from done and many significant changes are still coming. As our reviews have shown, these products generally promise long, deliver short and will interfere with nearby networks. And if that isn't enough, only one manufacturer - ASUS - is guaranteeing upgradability to the final 802.11n spec when it is released sometime next year. In their efforts to differentiate themselves, manufacturers have come up will all sorts of permutations on the "N" theme, making it difficult for the average consumer to know what he or she is really buying. So here's a partial list of draft 11n "marketingese" so that you know what to avoid: RangeMax NEXT (Netgear) RangeBooster N (D-Link) N1 (Belkin) Wireless N-Draft (Trendnet) Wireless-N (Linksys) With that said, you'll get the best combination of range and performance from products using MIMO chipsets from Airgo. Airgo's first-generation "True MIMO" chipset is at the heart of the Belkin Pre-N and other routers. But instead of the Belkin, which is short on routing features, a better choice would be the Netgear WPNT834 RangeMax 240. Although the 240 uses Airgo's third-generation chipset that includes "ACE" technology, which can interfere with neighboring 802.11b/g networks, you can shut it off and still have a product that will keep both you and your wireless neighbors happy. Netgear WPNT834 RangeMax 240 Wireless Router Join our discussion on this topic

• Ever since the days when 802.11a/g grew a second antenna, we’ve had “transmit/receive diversity,” which sends the same data stream out over multiple antennas and simply lets the access point select whichever antenna is receiving the best signal. Applied to 802.11n, transmit diversity used multiple antennas to help increase range and better deal with difficult locations. This is why 11n does a generally better job than 11a/g at eliminating dead spots. However, 802.11n equipment got another jump in intelligence with the addition of maximal ratio combining (MRC). This technology combines multiple antenna signals in such a way that strong signals are multiplied while weak signals are attenuated. The signals you want get boosted, while those you don’t have their power cut. MRC is built into all 802.11n chips. Now, as you might expect, the receiving end can play an important role in optimizing chip-based beamforming. With 802.11a/g, access points could listen to the client and use rudimentary MRC analysis to boost power along the best-suited beam, providing a gain of roughly 1 to 2 dB. The catch here is that the access point was doing all the work. There was no active feedback coming from the 802.11a/g clients. With “implicit beamforming,” wherein an 802.11n AP is communicating with 802.11n clients, you can have some feedback. Rather than having the access point perform all of the signal analysis, it can query the client and see if it agrees that this or that particular beam orientation is optimal. Having this limited two-way communication yields a maximum of 3 dB additional gain, but the bad news is that there are currently no products on today’s market supporting implicit beamforming. With “explicit beamforming,” feedback between the AP and client happens much more frequently. This way, if a client moves or an antenna gets adjusted or anything happens to alter the dynamics of the signal strengths, the system is able to adapt almost instantaneously to a new, optimized configuration. Again, having the client involved in this way can yield up to a 3 dB benefit with two radios, but there are no products available today offering this capability. Hopefully this will change. See more products D-Link DGL-4500 Xtreme N Gaming... Dell Home $199.99 Buydig.com $179.99 Newegg.com $149.99 PC Connection $185.95 ElectronicsPLUS $186.99

• Turning the Knob on Bandwidth The current wireless card going into Centrino notebooks is the WiFi Link 4965AGN PCIe — by all standards, a solid representation of the latest networking technology. The benefits of 802.11n are still in draft form; the task group has approved draft 4.0 and is now working on draft 5.0, so who knows when we’ll see a concrete standard. Nevertheless, Intel is revamping its entire lineup of wireless notebook adapters for Centrino 2 with four new models. The WiFi Link 5100 and WiFi Link 5300 should be available within the next month, while the WiMAX/WiFi Link 5150 and WiMAX/WiFi Link 5350 will go on sale later this year. The difference between the first two and second pair is, of course, WiMAX support. When we asked Intel about the readiness of WiMAX infrastructure to give the 5x50 cards some value, its response was: “WiMAX provides much wider Internet and phone voice coverage, and unlike Wi-Fi, has the ability to unwire entire cities or communities, [ensuring connectivity] even when on the move. Intel is working with service providers around the world to deploy WiMAX networks, with initial U.S. network availability starting later this year from Sprint XOHM and Clearwire.” In other words, even if Centrino 2 were immediately available with WiMAX hardware, it’d idle until the wireless networks came online in your area. What, then, is there left to add to the Wi-Fi-only cards that’ll make notebook vendors want to spend as much as $30 on them? Well, according to Intel, the new wireless offerings are going to zero in on three things. First, there should be a big step up in performance. The entry-level WiFi Link 5100 is expected to receive files at up to 300 Mb/s using a 2x1 MIMO configuration. The higher-end WiFi Link 5300 gets a claimed 450 Mb/s using a 3x3 antenna setup. Incidentally, the 4965AGN should also deliver up to 300 Mb/s, putting the 5100 on par. We’re going to assume that Intel is employing the same technology that Marvell uses to get 450 Mb/s out of three sub-streams with its TopDog 11n-450. It isn’t clear whether or not you’d need a router built on a particular draft of the 802.11n specification to take advantage of the faster data rate, though. Intel is also shooting for power savings with the new 5000-series WiFi Link cards. It cites consumption numbers at idle, associated with a network, at less than 25 mW. It also claims to offer significant reductions in power consumption and increases in power efficiency, but fails to provide the data to support those percentage increases. Finally, the new WiFi Link cards include support for Active Management Technology 4.0, helping tie Centrino 2 into Intel’s more enterprise-oriented vision. A notebook boasting Centrino 2 with vPro technology includes the Core 2 Duo chip with Virtualization Technology, a Mobile 45 Express Chipset with the ICH9M-Enhanced controller (a $5 BOM increase), the 82567LM Gigabit chip with AMT 4.0 support, one of the new WiFi Link cards with AMT 4.0 support and a Trusted Platform Module v1.2. With all of those pieces in place, IT administrators can manage wireless clients, even if they’re powered off. We’ve seen this functionality for a while now on wired systems, but it’s brand new in the notebook space. With that said, only the enterprise folks will really care about its implementation. Intel hasn’t yet started talking about pricing on the 5x50 cards with WiMAX support, but we can’t help but think that they’re the biggest piece of this Centrino 2 story. All of the other components really just represent incremental improvements, but WiMAX is completely new. If you’re going to spend a grand on a notebook that won’t be replaced for another couple of years, it really makes sense to wait and see how the metropolitan networking technology unfolds in the next six months.