Multiple Access Points (outdoors)

[gguerra]

I am in the process of setting up a wireless LAN at my place of work and need a little advice.. We will using portable handheld devices (scanners) throughout our location. We will need two or more Access Points to cover our area.. It is a steel fabrication shop that covers at least 3 or 4 acres, most of it is clear line of sight.

What brand and type of AP should I use? I'm looking at Cisco 1200 series AP's.. They are expensive (around $700 each) but should be the best and most reliable right??

As far as configuring the AP's so that our clients can seamlessly move around the area without losing signal; Do I use the same SSID but different channels??

Any advice would be appreciated..

 

[halo71]

When you say scanners, you are talking about something like RFID scanners? Are the scanners going to run Windows? Or some WMS program? FRom the sounds of it you will need more than 2 AP to cover that area. Right now I am sitting in an office attached to a production warehouse that is roughly 1 million square feet running 22 AP's. Just to compare.


btw, Welcome to Techspot!!

 

[gguerra]

Yes they are Symbol MC 90XX portable handheld devices running Windows CE, (I dont have the specific model) I'm pretty sure they are dot g capable. Basically they are handheld computers with touch screens and built in bar code scanners. As far as the area that I need wireless it is approx 150,000 SF with a ceiling height of about 50ft with no walls only steel columns that hold up the ceiling. I may have exaggerated the 3 or 4 acres figure.

 

[halo71]

I have used Symbol in the past, currently using Intermec. On a 2.4 system, 1 access point will cover around 50,000 sq. ft. Some may say more, some may say less. But in an open line of site building, during testing and set-up. I have seen roughly 50,000 sq.ft. as having good coverage. So you may need 3 AP's.

 

[gguerra]

What brand do you recommend... Can I use a linksys or should I spend the extra $ on cisco.. I was also looking at Symbol . also what type of antennas?

 

[halo71]

I have never used the Linksys AP's in this type of application. The ones that you would get from Intermec or Symbol, that have their name on them, are probably made by Cisco, just guessing. Intermec, who we use now, are pushing the Ciso branded AP's as well as controllers etc.

As far as antenna's go, it depends on what system you are installing. We currently use the Cisco 2.4 GHz Aironet antenna's. But there are 5 GHz systems out there as well. So of course, if you are running a 2.4 system, use 2.4 anntenn's. And on a 5 GHz system, use 5 GHz anntenna's.

Also assuming you will run the AP's on fiber from the warehouse to a computer room? I like the BlackBox brand of Fiber to Data converters. We have little problems with them.

Check out the information for Intermec here

 

[gguerra]

We will be using Cat 5 to link the AP's to the network. I was planning on using either Symbol or the Cisco, probably the cisco. I will be using 2.4Ghz antennas but was wondering about the gain does the db rating matter.. We've gotten a coupule of quotes from outside companies one offered a 5.2dBi ceiling omni antenna and the the other company offered 8dBi omni. They also offered a RP/TNC cable which I assume is used to mount the antennas away from the AP and at the highest point possible?

 

[halo71]

Your going to run CAT5 that distance? I am not sure what db rating the ones we use are. RP/TNC means that the AP will acept that type of anetta. MOst of the newer stuff is like this I believe. The antenna usually mounts upside down, from the ceiling rafters, around 8 feet away from the AP. At least that is what we have always done. If you do not need coverage outside the building I wouldn't mount the AP closer than around 50ft. from the walls either.

 

[gguerra]

The AP's will only be about 100 ft (at most) from the office and the network.. From there I should be able to get good coverage for the rest of the shop which is where I need the wireless so I dont need fiber.. Another question.. is 110 meters the effective range of dot g wireless. Can I increase that number by using a high gain antenna?? I guess I'll have to run some tests using a laptop..

 

[halo71]

So you are planning on putting all 3 AP's around 100ft from the server/switch in a 150,000 sq. ft. building? I think you will have issues with covering the entire building like that. Yes you can increase that range with a HG antenna.

 

[gguerra]

We our LAN is segmented and utilizes multiple switches located thoughout the building. I didn't set it up it was already like that. But that being said we did have a company come in and do a site survey and they came in and ran some tests using their equipment (I think they used cisco). I think the db rating designates the "gain" of the antenna.. the higher the db rating the higher the gain. I will do more research on this though.. Thanks for the replies

 

[halo71]

No problem! Let me know how it works out! Hope I gave some useful information. If you check out that Intermec link I posted above, you may find some useful information there.

 

[Tedster]

the best thing would be to get a router and several wireless access points. Run cat-5 from the router to the access points. Ideally your access points should be self powered.

Your access points should run on different channels in order to avoid self-jamming. However as clients move about, they will need to reconnect from one antenna to another. If you space the APs far enough, you can use the same channel. You will have to experiement to see.

 

[halo71]

Tedster, that is pretty much what we have been talking about. Usually the AP's don't run on the same channel. If they for some reason loose their connection by the fiber/cat5. They then piggy back wirelessly off the next closest AP. So they do not go down totally. In an industrial type application as this, I have never heard the term self-jamming.

 

[tipstir]

That's correct! They don't run on the same channel if they did then all hell would break loose as they say

Each AP has to fallback the CAT 5E or CAT6 or higher even those from Tyco that uses 9-pin feature in the copper cables to monitor connections you need to have the APs connected via whatever switch your using or fallback Tyco Network Hardware Analzyer (btw good product just way to expensive for most corp needs)

Network jamming is rare, but can happen since most AP are using 2.4GHz range the 4th Generation suppose to be using 5.8GHz with 800Mbps using N 4th.