NAS speed and wireles LAN speed

[JBallant]

I don't have much experience with NAS but I think an NAS would be a good solution for my very small office to back up several computers and have a central file storage configured in RAID-5 (while keeping original files on the client pcs as well). Ideally, we would occasionally backup the NAS to another external usb drive as well in case the whole array gets corrupted. And the only other main feature would be one with ftp so we could remotely access files and perform incremental backups.

The main problem I am facing is determining what kind of speed makes sense. We are on a wireless network right now and some of us are only able to get ~20mbps as their LAN speed. While this will hopefully be improved in the near future, this would mean that a fast NAS that can write at 60+ MB/s would face massively wasted potential, or am I misinterpreting? People complain about the speeds of NAS units that only get 30MB/s but to me that seems like way more than we could handle anyway. Is a 20 mbps connection too slow to think of using an NAS to backup anything of a significant size (over 1 GB)? Thanks in advance for any suggestions or info you provide.

 

[Jesse B]

20Mbps is quite slow, yielding only a maximum [theoretical] transfer speed of ~2.5MB/s, inadequate for almost any application.

ex.) a 750MB .ISO would take ~5 minutes to transfer assuming you're achieving maximum throughput.

My suggestion would be to upgrade your office's network. Yes I know this costs money, and yes I know that small businesses have small budget, but this is your only realistic option to attain speeds that are at all usable. A gigabit network should give you ~100MB/s (plus or minus 10Mb/s+ depending on a multitude of things), and shouldn't set you back too much money.

 

[JBallant]

Thanks for your reply.

I think and fear you may be right. Still, while backing up 100GBs of data would take ~12 hours at that speed, if I could ramp up the wireless speeds to 60Mbps (with say, a solid wireless-n router, a powerful antenna and good adapters), that decreases the time to ~4 hours (assuming 100% efficiency and correct math). That might be tolerable if we only do that for initial backups and for incremental after that. Nevertheless, this makes the network drive not nearly as convenient and usable as it would be with wired 100MB/s connections.

I will probably have to spend a fair amount of time analyzing how much this office would actually utilize a much faster (100 MB/s) LAN connection versus how much it would cost us. I really don't like having to manage people backing up to external USB hard drives.

 

[Jesse B]

Upgrading your network will make drastic improvements in transfer speeds, which is obvious. You said you have a very small office, so there's no need to spend oodles of money on commercial-grade routers and network equipment. Some nice home-grade stuff will do just fine (assuming your office is indeed "very small". How many computers is it, just curious?).

The generic el-cheapo wireless routers will give you a 54Mbit wireless connection, effectively doubling what you have now. If you could get all/most of your computer wired into the LAN, 100Mbit routers are practically free, and Gigabit routers are very affordable. Obviously this would be the best route and give you the best speeds. If your computers have to utilize the WLAN, then you could simply add a Wireless Access Point (WAP) to your existing network, depending on it's configuration. You could also just invest in a new router. My wireless N router that I purchased claims 150Mbit wireless speeds, although I'm not sure how accurate that is. Even still, that would most likely put you close to the speeds that a wired 100Mbit connection would give you.

I'm kind of ranting on here, as there's dozens of options that you could do. I named a few that are the best in my mind, but it's very difficult to make suggestions without knowing the exact configuration of your network and office, which I can't really do without physically being there. If you like one of the options above, or have another idea, let us know and we can do our best to help you get set up.

Good luck

 

[claykin]

20Mb/s throughput is typical for a Wireless-G network. Wireless-N will yield 60-70Mb/s in single channel and up to double that in two channel (40Mhz mode). Both router and client must be a 2x2 radio design to use 40Mhz.

That said, I would not recommend a regular use of Wifi to do large multi GB backups. Wifi is too unreliable to expect a reliable and continuous connection while sending 10's or 100's of GB to a NAS for backup. Its just impractical for everyday use. Once in a while, fine, but not for everyday. Plus, most backup software will keel over when the Wifi connection breaks momentarily. There's a few apps that will allow a period of waiting when backing up over a LAN connection, but you'll need to test to be sure. Genie Backup is one that comes to mind that handles broken LAN connections somewhat gracefully. That said, Genie backup has other issues....

I recommend a Gigabit wired network which will yield an end result you'll be happier with.