Fast Wi-Fi's Slow Road To Standardization 140
Posted
by
timothy
from the vested-interests-took-off-gloves dept.
from the vested-interests-took-off-gloves dept.
CWmike contributes this excerpt from Computerworld: "For a technology that's all about being fast, 802.11n Wi-Fi sure took its sweet time to become a standard, writes Steven J. Vaughan Nichols. In fact, until September 2009, it wasn't, officially, even a standard. But that didn't stop vendors from implementing it for several years beforehand, causing confusion and upset when networking gear that used draft standards from different suppliers wouldn't always work at the fastest possible speed when connected. It wasn't supposed to be that way. But, for years, the Wi-Fi hardware big dogs fought over the 802.11n protocol like it was a chew toy. The result: it took five drama-packed years for the standard to come to fruition. The delay was never over the technology. In fact, the technical tricks that give 802.11n its steady connection speeds of 100Mbps to 140Mbps have been well-known for years."
Re:Blueray of Wifi (Score:4, Informative)
BG is good enough, tied to residential/office network, and hard to notice the benefit of N.
Do you do much copying of files at all? We can see a huge difference on our network (have had n since the first 11n Airport Extreme), with speeds 3-5 times faster than G in the same environment. For us, 11n actually made wireless an acceptable alternative.
Re:Not the first time (Score:3, Informative)
Re:Not the first time (Score:4, Informative)
Or alternatively you could spend your time doing something enjoyable. The reason wireless is more widespread than wired in home networking is because it's convenient. If you have loads of free time to wire up your house good for you but don't knock those who'd rather do something else instead.
Re:Blueray of Wifi (Score:5, Informative)
Wired Ethernet is a reliable and mature technology that pretty much always works. While the vast majority of wireless routers are crap, it's quite easy to purchase a quality Gigabit Switch, and pretty much any wireless router will provide stable wired connections. People seem to ignore the fact that wireless only provides shared speeds while wired ethernet provides dedicated bidirectional bandwidth per port. In addition, the stated maximums for wired ethernet provide a sense of real world speeds while wireless does not.
For example, 802.11g provides real-world speeds of 20-25 Mbit/sec - not the 54 Mbit theoretical speed pasted on the box. 802.11n is advertised as 300 Mbit/sec but generally provides 100-130 Mbit/sec at best. However, these speeds can only be obtained with a line-of-sight connection at a short distance - a distance so short that you could easily connect over wired ethernet and obtain 10x the speed! At 100-BaseTX I am able to obtain 90 Mbit/sec after network (94 Mbit/sec with Jumbo frames). With Jumbo Frames Gigabit can achieve 950 Mbit/sec or higher speeds.
So, 802.11n in a best-case scenario (little interference, 10 ft from the AP) provides speeds only slightly in excess of 100-BaseTX, a standard formed 14 years ago (1995)! If you actually connect from any significant distance, 100-BaseTX will provide better speeds. In addition, you get dedicated upstream and downstream per-port bandwdith on 100-BaseTX.
Gigabit switches with Jumbo frame support can now be had for less than $30 - and in some cases $20. Nearly all laptops and desktops now come with Gigabit NICs and support Jumbo frames. Modern dual and quad-core CPUs can easily take the overhead of transferring at gigabit speeds with or without jumbo frames. Furthermore, modern OS's are more efficient at high-speed network transfers.
Yet, I see 802.11n routers advertised for streaming HD video, system backups, and large file transfers. Would you really want to backup 100 GB over 802.11n? Sounds like fun watching your entire network come to a crawl for 3 hours. Gigabit ethernet over Cat 5e/6 is generally limited only by your hard drive setup, and can be used for all the aforementioned tasks without any impact on network performance.
The following is my recent experience with wireless networking:
I use a WRT54GL with the Tomato (Linux) firmware. This provides a rock-solid solution, yet I was getting dropouts on wireless at my current apartment. I know it's not the router as it worked fine in my cinderblock college dorm, and I have another WRT54GL running Tomato at my home in NJ - which usually is up for months at a time - until a power outage.
At my latest apartment, I was getting constant dropouts on wireless. I ran a second AP to get a stronger connection. The connection was indeed stronger but I still got intermingle dropouts. I tried changing the wireless channel, antenna placement etc. but nothing worked. Finally, I just said fuck it, bought a 100' Cat 5e cable for $8 and ran it directly from the ADSL router to the router in my room. No dropouts since then - and I get more consistent and faster speeds.
I purchased an 8 port Gigabit switch with Jumbo Frames for my internal network and now my network speeds are limited only by my hard drives. Transferring between a 1 TB eSATA and 1 TB SATA drive, I was able to transfer a 12 GB file in 2:15 at an average speed of 95 MB/sec - around 800 Mbit/sec. With
Re:Not the first time (Score:2, Informative)
Actually, unless your ISP is hitting you with false data of some sort, your 6mbps connection is definitely faster than 802.11b.
The effective throughput of wifi is only a fraction of it's media speed - on the order of ten to twenty percent. It's also adding measurable latency to the connection. And upwards of a few percent of packetloss, in most installations.
A 10 mbps connection should be able to transfer at 1,250 short kilobytes per second minus overhead. Not 125 or 250.
Granted, you're better off just wiring quality cat5e. You can run 10/100/1000 megabits over it, with a strong guarantee of future proofing against upgrades to your internet connection (ADSL2+, that is, ITU G.992.5, can handle 24 megabits/sec in the highest profile for instance), as well as the ability to hook in devices like NAS/fileservers and such. Also you don't have to worry about the fact that your legacy B gear is running WEP, which someone else is using to access your 6mbps connection to download something the FBI is very interested in right now.