Editor's note: We will be changing how we send out Network World newsletters over the next few weeks. To ensure future delivery of your newsletters, please add nww_newsletters@newsletters.networkworld.com to your e-mail address book or 66.186.127.216 to your white-list file. Thank you. 802.11n complications are imminent As you likely know, the current fair-haired wireless LAN version, 802.11n, is multidimensional, making product comparisons challenging. Those comparisons are likely to soon get even thornier when 1x1, single-stream 802.11n products emerge for netbooks, smartphones and even laptops. At issue: the Wi-Fi Alliance currently lacks certification programs and categories to accommodate this new breed of 802.11n product. MIMO, antennas and streams - oh, my! 802.11n's intimidating nomenclature contains such mysterious terms as multiple-input, multiple-output (MIMO), spatial streams and spatial multiplexing, which can quickly freeze a network manager's brain. What do these specs really mean in the context of a real-world 802.11n wireless networking environment? What 802.11n tech specs mean 'We established in the last newsletter that you need multiple transmit and receive antennas working in parallel (a.k.a. "MIMO" technology) to conduct spatial multiplexing. We also learned that spatial multiplexing is a mandatory component of the 802.11n standard and is the primary means to 802.11n's increased throughput promise. (Compare Enterprise Wireless LAN products.) But what's the ultimate difference in so-called 2x2 and 2x3 architectures, if they both support two spatial streams? How we tested the WLAN gear We assessed enterprise-grade 802.11n systems in terms of pure 802.11n throughput and latency; mixed-mode (802.11n plus both 802.11g and 802.11a clients) throughput and latency; "WiMix" traffic handling, which comprises ... What's next for 802.11n? One of the more controversial elements of Draft 2 of the 802.11n standard is whether one should purchase products based on it today. Analysts are split on this issue. AT&T Plans to Double 3G Speeds AT&T is doubling the download capacity of its HSPA 3G network just before a new iPhone device is expected to launch. The new speeds take AT&T's capacity from 3.6 Mbps to 7.2 Mbps for 3G devices. Called HSPA+, the tweaked network is currently in two test markets and will roll out across the country later this year, according to Telephony Online. Are you a CCNA wireless candidate? If so, Cisco Subnet blogger Brandon Carrol has rounded up five links to resources that could prove helpful to you. Cisco IoS Dial-Peers: 11 digit dialing Cisco Subnet blogger Dennis Hartmann continues with a dial-peer example for providers that require 11 digits to route long-distance calls. iPhone 3.0 OS Upgrade Could Be A Rough One Mitchell Ashley, in his Converging on Microsoft blog, explains that the new iPhone OS 3.0 beta is rich with updates, upgrades and new features. But it's worth reading the proverbial fine print (a README file in this case) before any developer installs the 3.0 OS and SDK. April giveaways galore Cisco Subnet and Microsoft Subnet are giving away training courses from Global Knowledge, valued at $2,995 and $3,495, and have copies of three hot books up for grabs: CCVP CIPT2 Quick Reference by Anthony Sequeira, Microsoft Voice Unified Communications by Joe Schurman and Microsoft Office 2007 On Demand by Steve Johnson. Deadline for entries April 30. Network World on Twitter Get our tweets and stay plugged in to networking news. |
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