Possibly stupid Fiber Optic question, but I'm going to ask it anyway...

[Glendor]

Can two fiber optic NICs be hooked up peer-to-peer like two ethernet NICs can when you use a cross-over cable? If so, how fast would the connection be?

Thanks in advance,
Glendor...

 

[Tallgeese]

10FX, 100FX or 1000FX?
or some other standard?

 

[Garion]

Sure, just make sure the two ends are exactly the same flavor - Don't try to link a 100BaseT over Fiber to a gigabit using an SX GBIC, for example.

To get it to work you just need to cross the send and receive fibers.

- G

 

[Tallgeese]

Also make sure you don't mix Short-Haul and Long-Haul transceivers/adapters or cabling.

At best, you'll have hideously poor signal quality.
At worst, you'll have burned out equipment, or a fire :Q

 

[aberant]

an intruige - 10BaseFX = FOIRL !! discovered this when playing with some whittaker cards

 

[ScottMac]

FOIRL is NOT the same as 10FX. Fiber Optic Inter-Repeater Links were not designed for host access. 10BASEFX (which came later) was designed to accomodate host connection. FOIRL was designed for the "long haul" hops between repeaters/bridges.

That's the way I remember it anyhow.....

FWIW

Scott

 

[dbcrossfire]

it would be really dayum fast.

 

[ScottMac]

Actually, I've been told the physical transmission of light through fiber is usually slower than the electrical signal through copper. I don't remember the specifics, but it relates to the transmission mode of the light, the NA of the fiber, and some other stuff.

The person that explained it was an EE that specialized in transmission systems, and it sounded right at the time.


(of course, I own a bunch of bridges that I'll be moving to some recently acquired swampland.....)

I believe it's true, maybe some of the physics-oriented folks can shed some light (no pun intended) on the subject.

The best coaxial stuff I've seen had a velocity factor of ~86%, perhaps it's conditional on the type of medium (single mode might be faster than multi-mode, some copper conductors have slower velocity factors, etc).

FWIW

Scott

 

[Glendor]

Thanks for the advice and comments. I was hoping that (if it would work) it would exceed 100mbps, otherwise, it isn't worth doing since I have 100TX ethernet already installed. It seemed like an interesting project when I saw some Fiber Optic NICs selling for $10 + shipping recently. Anybody else want to comment on the viability of this project?

Glendor...

 

[Garion]

The cable type really doesn't affect the speed of the connection - It is 100% dependent on the network card. You can run fiber at 10Mb/s and copper at gigabit speeds. If you're purely looking for speed, $10 NICS aren't going to get you anything and will probably be slower.

- G

 

[ScottMac]

If they're 10BASE-(anything), you get ten meg max. 10 Meg fiber is slightly faster (Codenol once said upwards of 10-20%) because of environmental considerations and the inherent full-duplex nature of fiber transmissions (in networking).

Fiber jumpers will end up costing you more than the NICs. I haven't looked recently, but I think six footers are still ~US$30-50.00.

FWIW

Scott

 

[aberant]

not that i want to start a flame war, cos i'm a nice guy. i think you'll find that FOIRL and 10BaseFX are the same - the names are used interchangebly - perhaps FOIRL was invented for the usage u suggested and was then ratified or some such, and became used in hosts, as i know for a fact that you can connect a 10BaseFX card to a FOIRL concentrator - i'm on the net right through it. However, if you have some information that rebukes mine, please pass it on, i'm always looking for new things to learn.

Thanks m8

 

[Garion]

FOIRL was designed as a way to transport 10BaseX Ethernets over fiber. Think of it as a proprietary fiber-based repeater system for 10BaseX networks. It is only hub-to-hub.

10BaseFL is actually a Layer2 protocol for the encapsulation and transmission of Ethernet frames over fiber at 10Mb/s, much like 100BaseFX and 1000BaseSX/LX. 10BaseFL supports host connectivity and also hub-hub connectivity.

In short, one is a proprietary bridging system via fiber and one is true Ethernet via fiber.

Look at this link for more details.

- G