Is Centrino a must have, or will a simple Pentium-M do?

Today's launch of new mobile technologies from Intel raises some interesting questions about the finicky nature of wireless connections and provides fertile ground for confusion when it comes to buying notebook computers.

Intel formally released the Pentium-M (formerly code-named Banias), a new processor that raises the bar on performance while improving battery life. Simultaneously, Intel released its own 802.11b wireless adapter technology, which includes the radio transmitter and related hardware and software. Formerly code-named Colexico, Intel's Intel PRO/Wireless 2100 is much like the Pentium-M in that it's optimized for the performance and power requirements of today's mobile environment.

In addition, Intel introduced the Centrino platform, which is a combination of a Pentium-M, PRO/Wireless 2100 package , and one of the members of Intel's 855 chipset family. Pentium-M notebooks that lack the Intel radio do not qualify as Centrino systems, and nothing prevents Pentium-M notebook manufacturers from selecting a different wireless radio or leaving the radio out altogether for different configurations.

For notebook buyers, the availability of the new Pentium-M in both Centrino and non-Centrino systems begs the question of whether any significant benefits accrue by sticking with the all-Intel configuration.

The absence so far of an 802.11a option or, on the more bleeding edge, one based on the draft 802.11g specification are worth noting. The main differences between 802.11b, a, and g are the speeds and radio frequencies. Whereas 802.11b maxes out at 11 mbps over the 2.4 GHz frequency, the more recently available 802.11a standard goes up to 54 mbps but works in the 5.0 GHz range. 802.11g will offer the speed of 802.11a (54 mbps) using the frequency of 802.11b (2.4 GHz), which means that a single 802.11g radio (cheaper than having two radios) should be able to support the choice of 11 mbps or 54 mbps speeds.

To the extent that you want notebooks to connect to 802.11a or 802.11g networks, Centrino-based systems won't play unless the built-in radio is disabled and a third-party adapter is added. Mac Agan, Intel's wireless marketing director, anticipates that a dual-band (802.11a/802.11b) PRO/Wireless 2100 offering will be available by mid-year and that an 11g offering will follow when that standard is finished. But according to Agan, "[Intel] has no comment on the upgrade path should the buyer of an 802.11b system want to upgrade to 802.11a or 802.11g at some point." Given that the PRO/Wireless 2100 offering is based on the Mini-PCI specification (which means that the adapters shouldn't be soldered into the motherboard), you should check with the notebook manufacturers to see if they're willing to provide you with an acceptable upgrade path. Given that Mini-PCI connected adapters are usually not serviceable by end users, upgrading (if it's allowable) may involve returning the system to the factory.

Do the Centrino-based systems offer any significant advantage over their non-Centrino competitors? Based on the test results from our reviews, there's no way to tell. For example, the non-Centrino-based IBM ThinkPad T40 turned in the best battery life (a whopping 7 hours) of the bunch. Without testing two systems that are identical in every way but the radio (something we were unable to do), we can't know for sure if Intel's PRO/Wireless 2100 is any better or worse than other radio options. That's because so many other design considerations on behalf of the notebook manufacturer factor into power consumption. For example, in our tested configurations, the ThinkPad had a much bigger and more capable battery than the competitors' systems. But choice of other components -- such as displays, hard drives, and memory-- affect power consumption as well. In these respects, none of the tested systems were alike, thereby making the task of isolating the PRO/Wireless 2100's battery prowess impossible to determine.

Even so, Intel believes that it has done some pretty nifty things at the software level that are unique to the PRO/Wireless 2100.

Adjusting to connectivity changes
One of these improvements, according to Intel's Agan, is a Centrino-based notebook's ability to maintain application state despite any connectivity changes. If, for example, your Centrino-based notebook is hard-wired to a 100 mbps Ethernet and you disconnect the network cable and take your notebook down the hall to a meeting where wireless connectivity is available, the PRO/Wireless 2100 automatically detects the change and adjusts the notebook's connectivity. Network applications you were running, such as e-mail, should continue to run as though nothing changed (assuming that they're not overly sensitive to simple network disruptions). Then, if you head out to a Starbucks with a hot spot, the notebook will again detect the change in wireless environments and know, based on profiles that you set up, that connecting to your company's resources requires a virtual private networking (VPN) tunnel. Currently, the PRO/Wireless 2100 supports VPNs from Cisco, Checkpoint, Microsoft, and Intel, Agan said.

In addition to being able to run seamlessly on a LAN that's based on Cisco's proprietary wireless gear, the PRO/Wireless 2100 is also compatible with the latest developments on the wireless security front. For example, it supports the 802.1x, TKIP, and WEP security specifications as well as Wireless Protected Access (WPA)--the Wi-Fi Alliance's current stepping stone to the heavily fortified, but so far unfinished, 802.11i wireless security standard. The relevance of this support will depend on whether you've certified Windows XP for your environment or if you plan to by the time you buy your first Pentium-M-based notebooks. Out of the box, Windows XP makes working with these specifications relatively simple, and Intel's utilities for handling them isn't as necessary. Support for these specifications in Windows 2000, however, is not nearly as robust--you'll want a configuration utility that insulates you from the problems that could arise.

Intel is also engaged in interoperability testing to ensure that the PRO/Wireless 2100 hardware will effortlessly connect in most wireless situations, including public hotspots such as Marriott hotels and McDonald's.

"The interoperability testing that the Wi-Fi Alliance's (a nonprofit international association formed to certify interoperability of wireless LAN products based on IEEE 802.11 specification) does is not sufficient," says Intel Mobile Platforms Group promotions director Karen Regis. According to Regis, the Wi-Fi Alliance does a great job of testing for 802.11 standards compliance, but that interoperability doesn't take into account the other technologies like VPNs and DHCP (for auto-assignment of IP addresses) that are in play in locations like public hotspots. Intel claims that problems --- ranging from firewall misconfigurations to conflicting DHCP servers -- often hamper attempts to successfully achieve connections.

Whether validation processes like those Intel is undertaking will translate into a significant difference in the end-user experience remains to be seen. As more public hot spots become available, we'll know soon enough whether the Centrino brand means "guaranteed connectivity" or joins the cast of other current solutions that have failed to deliver wireless connectivity consistently. Intel's Agan admitted that much of the company's validation work has resulted in corrective action taken on behalf of the connectivity providers and not to Intel's hardware and software.

Do you need Centrino? Only you can answer that question.Certainly, the work Intel is doing to help the wireless community to clean up their act will benefit users and possibly earn Centrino a good reputation. In the meantime, Moore's Law marches on and ubiquitous connectivity is a step closer.

Check out our reviews of the newly introduced Pentium-M and Centrino system.

What do you think? Is Centrino a major advance for mobile computing? Have you had connectivity problems that could be solved by something like a Centrino platform? Share your thoughts with your fellow readers by using ZDNet's TalkBack below, or write to me at david.berlind@cnet.com.