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College to Deploy First 802.11n Network
Matt writes "Morrisville State College, a New York State school in central New York, is partnering with Meru Networks and IBM to deploy the first 802.11n wireless network. They will be using around 900 access points and are planning to go live this fall."
And they go straight to the next bleeding edge : 248 mbit.
_ Amendments
They have nearly filled the alphabet btw. Only 802.11z is still free as a name. Can you name them all ? http://en.wikipedia.org/wiki/802.11n#Standard_and
The key point is the difference between bits and bytes. A 10Mbps connection is a 1.25MB/s connection.
1.25 megabytes. Remember that a generic S-ATA or IDE hard disk writes at about 5-6MB/s and that can be a big bottlencek most of the time. So the 54Mbps connection you speak of is a total speed of ~7MB/s. That's not the internet speed. That's the LAN connection. So one person tries to send a large file to another on the network and all of a sudden we've hit that bottleneck and no one can even check their email.
Although some of these numbers sound impressive realistically for daily LAN usage they are just about usable.
I never get used to these constant resurrections
The 54Mbps refers to the signalling rate of the transmitter not the data rate that is acheiveable - bascially a maketing tools like MB MiB in hard drives.
The actual transfer rate is reduced from the optimum by the packetising of the data, obtaining the wireless spectrum before transmission and that an inter-packet gap is inserted between every transmitted packet to allow other AP users to transmit data.
A lot of vendors, I'm not sure of the one they are using, but Cisco, and a few other major players have guaranteed their draft equipment will work with the standardized 802.11n.
In a world of acronyms, the words are the real victims.
Because of the overhead, a single 54Mbps wireless connection, if on .11a or .11g only, can get as high as about 30Mbps. If there's a .11b device in range and a .11g AP is set for compatibility mode, it can knock the rate down to 10-15Mbps.
.11n, the theoretical rate actually maxes out at about 250Mbps. Factoring in the overhead, this allows, without compatibility mode, perhaps 150Mbps. However, the presence of any pre-.11n device knocks the channel width down to 20MHz from 40MHz, and then compatibility mode with .11a/b/g can knock it down even lower. Chances are that the actual bitrate with a relatively clean signal will be ~125Mbps, and the actual throughput will be somewhere around 70-75Mbps.
Under
One thing to keep in mind in all of this is that in many cases, the uplink on a switch to the rest of the network is only 100Mbps, so the final throughput from what people are used to isn't going to decrease all that much. Factor in several APs with a balanced channel setup with a gigabit uplink, and the experience shouldn't be all that different from what the wired people are experiencing.
You can never go home again... but I guess you can shop there.