Wireless network infrastructure for an office with 40 employees

Question

In my company we're facing connectivity problems due to our not very professional network infrastructure. We're growing now, and we expect to be 40 people at the office by the end of the year. I'm considering to set up a wired network with a structured cabling (Rack, Patch Panel, Switch, etc) but the shape of the office is not very pleasant to bring a cable to each desk.

Is is possible to set up a reliable wireless network for this amount of people? We're all developers, so we're going to stress the network. How would I go about doing this?

Answer 1

It might be possible, but here is a number of reasons why you do not want to rely on wireless only, and why you really want to roll out a structured wired network, at least as a fallback. Take this answer with a grain of salt, my experience is from the pre-N-era and might be outdated.

In a nutshell, wireless sucks. There are so many potential hazards - many of them with causes beyond your control - that you would not have on wire, and wifi is much harder to debug.

• Lots of non-wifi radio noise in the same frequency band: bluetooth, (non-DECT) wireless phone sets, non-bluetooth wireless mice and keyboards, badly shielded microwave ovens, ... the list goes on. All on 2.4 or 5GHz (though in Europe the 5GHz band is usually less noisy - if you can, go there)
• Nearby wifi APs that are not yours. If they are on the same 802.11 standard and/or channels, they might be 'collaborative' (proper bandwidth sharing, rather than mutual interference). If not, they are equivalent to just another source of radio noise
• A large share of the above radio noise is not under your control. There is not much you can do against noise from the next door office other than tinfoil wallpaper
• Even if the radio noise is currently not a problem - it might get much worse from one day to the other, e.g. when that crappy AP next door decides to switch channel.
• Wifi is a shared medium. The theoretical max speed on the AP label is usually the total bandwidth of all connections through this AP. Compare that to a GBit switch with >=10 Gbit backplane or more ...
• Did i mention that Wifi is a shared medium? You can have lots of collisions, in particular if the covered area is large enough that 2 station that cannot see each other use the same AP.
• Wifi issues are really really hard to debug without specialized hardware. Kismet can't tell you that the guy next door has a broken microwave oven. Wired Ethernet is so much easier to debug, in particular if you have good managed switches with a monitoring port and some nice debugging options on its telnet/ssh interface. And did i mention that you'll have much less problems to debug in the first place?
• I second thanasisk's point that everyone and their mother will bring wifi gadgets. This will double at least your client number.
• I second Evan's point that Wifi is harder to effectively secure against unauthorized access
• Wifi is so easy to DoS. A single rogue device (e.g. cell phone) can jam your whole wifi quite easily, and there is not much you can do against that. OTOH the source of a wired DoS attack can quickly be located and isolated.
• Developers are often bandwidth wasters who are blissfully ignorant about the side-effects of their doings. Avoid endless finger-pointing matches by giving them cables.

So ... Wifi at the work place is a nice-to-have perk. But if someone comes whining about bad network performance, you really want to be in the position to say "Here's a CAT5, just use that". And those Ultrabook people without Ethernet port: that's not a device to do professional work on in the first place. Go get a USB adapter.

---

Update: Added latter 4 points

Update2: If you still think relying on 802.11 only is a good idea, read this

Answer 2

How crowded the spectrum is in your area is going to be the biggest factor influencing your success. In environments where 802.11 has already been deployed densely your radios will be fighting for bandwidth with everyone else's radios. This will radically diminish the effective range of your access points. If you're serious about doing this you need to get some kind of spectrum analyzer to see how "noisy" the air is. (We don't do product recommendations here, but there are a variety of inexpensive spectrum analyzers out there that focus on the 2.4Ghz and 5.8Ghz ISM bands used by 802.11.)

Worse yet, you can't control how others use the air. What might be good spectrum today could turn bad tomorrow depending on what others deploy, and so long as they're not breaking the law w/ respect to transmit power, etc, there's nothing you can do.

The quality of your wireless access points (and, to an extent, their cost-- which serves as a bit of a proxy for quality) will be the biggest key to success or failure that you can control. Low-end access points will not support very many simultaneous clients, and will perform erratically.

Finally, the types of radios (and antennas) in your clients will make a big difference. You really should try the specific client devices and radios you intend to use in production as part of surveying the site.

I would echo the comment made by @thanasisk. You're going to have a lot closer to 80 wireless clients than 40 if you allow mobile phones to be joined. That's more than even a couple low-end access points can handle. You'll be graduating to more expensive APs right out of the gate.

In my opinion you'll spend less time and money supporting a wired network of that size versus wireless. The initial investment of time and money to wire such a small network will be more than eclipsed by the cost of quality wireless access points.

The cost of a 48-port 10/100/1000 Ethernet switch, likewise, will be a fraction of the cost of the access points. Low-end Ethernet switches, unlike low-end access points, actually work fairly well. You'll be sacrificing management and functionality in a low-end switch, but it'll still work well.

The reliability of a wired network, compared to wireless, is night and day. Even in deployments where I have very high-end access points I still see better bandwidth and reliability over the wired network.

Securing access to a wired network medium is also, in my opinion, easier than securing an equivalently-sized wireless network. Unless you're willing to move to 802.1x over shared-key encryption you run the risk that a former employee leaving the company will be carrying with them the credentials necessary to grant access to the wireless medium. Changing a shared-key in an environment with 40+ clients would be a nightmare. If you opt to go with 802.1x you will need some supporting infrastructure (RADIUS server, some type of authentication database) to support it.

If you had 5 - 10 clients I'd be more apt to suggest a wireless network, but I think that your situation is sized such that wired will end up being a "big win" over the long haul. It's small enough to make wiring fairly low-cost, but large enough that you're going to find wired to be a lot easier and cheaper to administer.

Answer 3

Efficiency of Wireless connections depends, like wired connections, on the traffic that goes on. but the problem with the first one is that the "air" is shared between every wireless device.

So having a good (strong) WiFi signal can really help not to lose connectivity in a file transfer between 2 machines. you also need to check if there is other wireless access points that are using the same channel as you. you can check that by installing any WiFi Channel Scanner.

In my opinion, not having wired connection make your network infrastructure very fragile.
Wireless is good, but not as good as wired connection.

I hope this helps.