Speed of Ethernet vs Firewire?

[johnnyv]

Hello all...

Does anyone know what the speed differences would be if you were making file transfers over Ethernet vs Firewire? When they say "gigabit" Ethernet, do they mean 1000bits per second? If so, then I guess the new Firewire 2, at 800bits per second, would be almost close to the Ethernet.

Am I correct in this thinking?

Thanks in advance?

J

[tvent]

Yep, you are right on point.

Data transfer rates are measured in bits when a little "b" is used and in bytes when a big "B" is used. Traditionally, network transfer rates are always measured in bits. Hard Drive transfer rates (up until firewire and usb came along) were measured in bytes. It seems as though the USB folks jumped over to using bits to make the numbers more impressive and I guess the firewire folks had to follow suit. Just simply divide the bytes by 8 when one is being represented differently so you can compare apples to apples and oranges to oranges.

Of course, there are no Firewire800 drives available as of yet...

Another thing to think about: the fastest of the fastest hard drives can transfer data at a maximum rate of about 50 - 60MB per second. These are those super duper 15k RPM SCSI drives. With that in mind, the bottleneck is at the hard drive interface (It is even worse with IDE and even more worse than that if using firewire because it has to bridge accross the Firewire to IDE interface).

Of course, 10MB per second is theoretically enough to support about 80 tracks of 44.1 24bit audio if nothing else is happening so I guess Firewire800 would net you about 800 tracks if the harddrive could keep up [img]images/icons/wink.gif[/img]

The real beauty of using Ethernet for file transfers is that you don't have to get up from your seat and disconnect anything! I would highly recomend it (Especially if you have Gigabit Ethernet on both ends!) Using a Firewire drive to move data from one computer to another manually is no different than using a floppy disk (except it will most likely break if you drop it on the way)

[tvent]

Thanks for clarifying that Tron.
Now that you say that it makes much more sense.
Sorry I falsely accused the markeing department [img]images/icons/grin.gif[/img]

[maxserg]

Hey back to school!!! [img]images/icons/grin.gif[/img]

[maxserg]

...No pun!!!

Me too back to school! [img]images/icons/grin.gif[/img]

[DaveP]

Originally posted by johnnyv:
Hello all...

Does anyone know what the speed differences would be if you were making file transfers over Ethernet vs Firewire? When they say "gigabit" Ethernet, do they mean 1000bits per second? If so, then I guess the new Firewire 2, at 800bits per second, would be almost close to the Ethernet.

Am I correct in this thinking?

Thanks in advance?

J

<font size="2" face="Verdana, Arial">It actually gets a little more complicated than this. You are comparing apples and oranges here and you can not just compare the "Theoretical" data rates. 1st off, when you are sending information across ethernet you are using the appletalk or tcp/ip protocol (assuming you are using Macs). These protocols use "packets", so the data stream from the drive needs to be divided into packets - then sent - then recombined on the recieving end. These protocols are not optimized for LARGE data transfers. Additionally you might be limited to network traffic if you are on a busy network. Finally, if you do not have a dedicated file server to handle network negotiations the negotiations have to be handled by the individual computers, slowing the transfers even more. I'm sure someone who knows more about network technology could tell you more, but in my experience I have found that Firewire 1 transfers work faster than Gigabit ethernet - if you do not have a dedicated fileserver. If you have a dedicated fileserver, then the speeds are about equivalent.

[The Chinese]

We have all 5 of the Major Commuication protocols in use at technicolor. IDE, SCSI, GIG Ethernet,Fibre Channel, and Firewire. The fastest is Fibrechannel, The next fastest is SCSI, closely followed by IDE and Firewire, with Gigabit Ethernet being the slowest. However, Gigbit ethernet is VERY Cool. you will NOT be able to play audio off it; as someone else said, it does send information in packets, which causes reassembly on the other end, which in turn prevents audio from playing. However, it its Great for FX libraries, File transffers, session uploads, etc. we have two networks established for each workstation A Fibre Channel for audio, and the Gig ethernet, running off Xserves. REALLY Cool. Hard to beat. we also have 100 Gig internal IDE drives on each box, along with a host of FW drives for transfer to our satellite editors.
-Todd A.

[lwilliam]

Well, you CAN play audio over ethernet (witness the cable modem connection to your pc or playing MP3s over the corporate net), it's just not the best protocol to use.

It's less efficient because it DOES packetize all data (IP/IPX/AppleTalk, etc). It's also optimized for "bursty" traffic (asynchronous) rather than isochronous or "time-dependent" traffic. You need to buffer it to ensure audio and video play smoothly. That introduces latency.

It is a little more like oranges and apples rather than two types of oranges.

Additionally, Ethernet is a contention-based system that doesn't guarantee every packet sent will be received and often must re-transmit packets when they've "collided" with other packets. It is not designed to operate well with isochronous signals such as audio and video. It also doesn't guarantee a particular throughput rate - it can get slow on crowded networks.

Firewire is designed to operate in both asynchronous and isochronous modes. Big difference.

Another difference is that Ethernet uses a broadcast-type of protocol called CSMA/CD (sends data out hoping a device will receive it), vs Firewire which is a peer-to-peer protocol. Firewire uses an "arbitration" type of protocol where one device gets to send it's data all at once vs "sharing" the bandwidth with other "contendors".

Bottom line: Ethernet is not a good way to send time-critical data such as audio or video. Firewire was designed with such transmissions in mind.