Firewire cable length limit

[bill2]

hi

I read somewhere that it is very important that the cable between the DV and the computer will be no longer then XXX f', otherwise it starts to drop frames.

Does anyone know what is the length limit for such cable?

Thanks

[cuddles]

I have a 2 meter one that works just fine (6'6"approx)

[Dr Mordrid]

The limit is 15 feet between devices.

Terry

[wkulecz]

Is 15' the limit for 1394 networking?

15' is useless for networking unless everything is in the same small room!

--wally.

[Dr Mordrid]

I looked up IEEE-1394 networking and this is what was stated:

"The cable bus, which is the subject of this paper, is a "non-cyclic network with finite branches," consisting of bus bridges and nodes (cable devices). Non-cyclic means that you can't plug devices together so as to create loops. 16-bit addressing provide for up to 64K nodes in a system. Up to 16 cable hops are allowed between nodes, thus the term finite branches.
>
>
Up to 16 nodes can be daisy-chained through the connectors with standard cables up to 4.5 meters in length for a total standard cable length of 72 meters. Using higher-quality "fatter" cables permits longer interconnections."

Dr. Mordrid

[wkulecz]

I thought 1394 networking was a really stupid idea before being aware of this limitation. 100BaseTX does 100m (~300') between devices with a simple cat5 cable. This sounds like a lot, but unless you can make your runs "as the crow flies" in a crawl-space or something, even 300' can start looking pretty short when you have to run around doors to avoid trip hazzards and/or bypass walls you can't drill thru.

--wally

[bill2]

Thanks Doc.

Very important information.

[droopy]

Question

@ALL

Why do all of you keep comparing IEEE1394 networks with normal networks or as replacement for them Talking about the often quoted apples and pears, here's your example.

It is NOT intended to replace a normal network. You've all already found the obvious and straight forward reasons for this.

IEEE1394 networking is just a VERY convenient way to transfer data, especially large amounts, between computers. It is a HUGE advantage that the implementation used is that of a normal network. This enables it to make it available for normal transparent networking through a simple software router.

As video amateurs, and a few of you even professionals, I would have guessed you would appreciate such simple, cheap and versatile solution. Most whom are using multiple PC's for video editing already have in each of them a OHCI compatible IEEE1394 card. I don't think you would have your different PC's 300 feet apart do you? What's easier to simply connect them giving you the ability to easily, quickly and CHEAPLY move data between them? When using w2k you get at least a stable 20~25MBYTE transfer rate. This is NOT a burst rate but an actual transfer rate. On TOP of that you KEEP the ability to at the SAME TIME use the remaining ports for connecting IEEE1394 storage devices or DV cameras. At least with Firenet you do.

It's speed is close to Gigabit ethernet without the extra expense of new network cards and possibly even cables. The only thing you pay for is an additional 6/6 cable and the license for e.g. Firenet. If you don't want to pay for it, you can use the microsof build in drivers. You compromise a big chunk of the possible speeds then though due to shitty microsof drivers.

I've seen a lot of wise information, discussions and great help on this forum. Heck, some of you even helped me out a LOT. Every now and again though I'm stunned by the sheer ignorance given on a possible good solution by some.

@Bill2
The offical standard length is 4.5 meters. Unofficially I want to tell you that I already have a problemless, this means no problems at all, connection with a cable of 10 meters. No repeaters in between.


Regards, Leon.

[wkulecz]

When the number of computers shipped with 1394 as standard equipment exceeds the number shipped standard with 10/100BaseTX then your arguement washes. Right now only XP supports 1394 networking out of the box (maybe winME? I've never used it). Most notebook builtin 1394 ports are only one 4-pin connector so you can't have your network and camcorder at the same time. I've yet to see a notebook with builtin 1394 that lacks 10/100 networking.

If you are willing to take responsability for problems caused by installing 1394 networking software onto random win9x, winNT and W2K boxes then you are a lot braver than me! One can expect 10/100BaseTX networking to simpley work if the network card was built in on all of these.

I do lots of adhoc networking with 100BaseTX and a simple cross-over cable, its pretty rare when I can use less than 25' of wire without creating a trip hazzard. A 15' node to node limit is a showstopper for me ~90% of the time. Maybe you have better insurance and can accept the liability for someone tripping over one of your wires.

A better solution for such things may be on the horizen if 802.11a or 802.11e/g can actually deliver the promised speeds which should be good enough for streaming DV wirelessly on a small adhoc network for 100-300' ranges. I've had good success with 802.11b wireless, which is faster than my cable modem but way too slow to stream DV (by a factor of 3 or 4X, the enhanced versions are supposed to be about 5X faster, time will tell.)

For now 1394 networking is in the why bother cataegory. If in a few years, if and when everything comes with a 1394 port and XP maybe I'll find 1394 networking useful to get my old data onto my new Mac :-) Sums up my feelings about XP!

I think a USB 2.0 version of networking will eclipse 1394 networking as Intel seems to want to jam USB 2.0 everywhere. Retrofitting USB 2.0 around here has so far been a nightmare with USB 2.0 devices not wanting to fall back to working with USB 1.1 ports on Win9x (W2K and XP have been fine, although XP has showed some major quirks but it has worked eventually).

--wally.

[droopy]

Sorry to be such an ignorant pig, but you totally missed my point.

IEEE1394 IS NOT MEANT TO REPLACE NORMAL NETWORKS. Its just a convenient alternative for PC's which already have a IEEE1394 card in them.

I don't even want to start on the notebook issue as that's an obvious one. It wouldn't work on those anyway as they do not supply power on the 4 pin connector. The same is true, but then not sufficient power, if you use a PCMCIA IEEE1394 card for them.

On another note, 10 unofficial meters are 33'.

So for the moment let's agree to disagree. I for one though, with my 2 editing PC, wouldn't want to miss Firenet for the world. It cost me Euro 70, being 1 license and 1 6/6 cable and now have a 20~25MByte STABLE network with 2 w2k machines. Just a info, the second license came with the non problematic Audigy player. I do worry a bit about that one as I have to admit that there seem to be loads of problems with them. So far so good though. By the way both my old Tyan dual PIII-700 and new MSI XP-2000 do not have onboard ethernet. Me single 60Gb USB 2.0 HD works with the MSI like a charm, both on the V1.1 and V2.0 ports.

Regards, Leon

[wkulecz]

OK I'm gald you are happy, but you could have got a pair of 10/100 PCI network cards and 100' of cat5 cable for under $30 US and be able to network with the rest of the world too :-)

How much was your 10m "unofficial" cable?

Needing 6-pin to 6-pin cables for 1394 networking is IMHO just another nail in the coffin, as its for notebooks that I generally need the adhoc solutions since I can't just plugin a PCI card. I keep a spare PCMCIA 10/100 network card in the camera bag for just such occasions.

USB2 has given me no trouble on W2k. Win9x has been major failure, XP plug and play messed it up, but I got it to work by installing a USB1.1 device first.

Like I said, its only if everything is XP and has 1394 built in when 1394 networking becomes a reasonable adhoc alternative.
I'll never be even mostly XP unless WPA is removed.

--wally.

[droopy]

Me last one on this!

I can, remember the software routers ;-)

Wlan 802.11b +/- 0,5MBytes/sec
100TP +/- 4,5-5,5MBytes/sec
Firenet +/- 20-25MBytes/sec

These are speeds measured using DU meter on 2 w2k machines with the transfer of 7.5GB divided in 2GB chunks.

HuffYUV 704*368 45 minutes equals +/- 7.5Gb (1 SVCD).

Datatransfer times are:

100TP +/- 26 minutes
Firenet +/- 5.5 minutes

Do the math. ;-)

1000TP or gigabit ethernet means investing in new cables (all 8 wires are needed) and cards. This is the only current alternative which comes close, or better even surpasses.

Euro 70 equals +/- $61.40
1 license = $49.95
1 10meter 6/6 cable = $11.45

Again, Firenet is not intended to replace, but just to be a convenient alternative with a lot of convenient advantages. That was the whole and ONLY point of me responding to this thread in the first place. I don't want to convince anybody and also do not have stock in Unibrain. To quote John Lennon, "Give good alternatives a chance". Or was he talking about peace, can't remember. Is that bad? :-)

Over and out, Leon