Help me understand Fiber...

[lukesterboy]

So I have a few questions of trying to understand Fiber connector types and a few other things on Fiber networks.

 

First thing is can any connector be on any end of  Fiber patch cable. For example, does it have to be LC to LC or can it be anything like LC to SC, or can it only work some ways like, for example, I know LC to FC exists but does FC to SC for instance? Sorry for the bad explaining.

 

Next, do you have to have the block connector things, not sure what there called but the things that hold each fibre cable side by side on when you plug it into an SFP transceiver, on to plug it into an SFP transceiver?

 

Can someone explain simply what is the difference between simple and multimode? I've watched a few videos but can't understand. I understand that ISP's use "Simple mode" when running Fiber, but that has nothing to do with simplex or duplex does it? Because they need to offer you download and upload which is duplex, right?

 

Last, so a Fiber switch is known as an FC Switch (Fiber Channel Switch), can this Switch accept any Fibre connector assuming you get a SFP/SFP+ (not sure what one) transceiver on the end of the Fiber cable connector?

 

Thanks. 

 

If my questions aren't detailed enough please do ask me what i mean I'll try to explain in more detail and maybe with pictures...

 

[ARikozuM]

It helps with digestion. @Electronics Wizardy might be able to help out.

[Electronics Wizardy]

21 minutes ago, lukesterboy said:

Can someone explain simply what is the difference between simple and multimode?

Do you mean single vs multi node fiber?

 

Single node lets one light path through, where as multinode allows multiple paths of light and allows bouncing. Single node can go much farter(hundreds of km). Normally multinode is used for short(less than 10km) fiber.

23 minutes ago, lukesterboy said:

Last, so a Fiber switch is known as an FC Switch (Fiber Channel Switch),

Fiberchannel is a completly different thing. Its a different standard than ethernet and used only for storage. You can run internet over it, but its mainly used for SANs. You can have ethernet fiberoptic switches aswell. A easy way to know the difference is that fiberchannel is always in multiples of 2 for speed, like 2, 4, 8,16 gb/s which ethernet is most often running at 1, 4, 10, 25, 40, and 100gbe.

 

25 minutes ago, lukesterboy said:

can this Switch accept any Fibre connector assuming you get a SFP/SFP+ (not sure what one) transceiver on the end of the Fiber cable connector?

Only compatible sfp's can be used, and it depends on the brand, but normally, you can run the native speed and one slower, so on a 10gbe switch you can normally use 10gbe and 1gbe sfp's

 

 

[lukesterboy]

4 minutes ago, Electronics Wizardy said:

Do you mean single vs multi node fiber?

 

Single node lets one light path through, where as multinode allows multiple paths of light and allows bouncing. Single node can go much farter(hundreds of km). Normally multinode is used for short(less than 10km) fiber.

Fiberchannel is a completly different thing. Its a different standard than ethernet and used only for storage. You can run internet over it, but its mainly used for SANs. You can have ethernet fiberoptic switches aswell. A easy way to know the difference is that fiberchannel is always in multiples of 2 for speed, like 2, 4, 8,16 gb/s which ethernet is most often running at 1, 4, 10, 25, 40, and 100gbe.

 

Only compatible sfp's can be used, and it depends on the brand, but normally, you can run the native speed and one slower, so on a 10gbe switch you can normally use 10gbe and 1gbe sfp's

 

 

20

I mean singlemode and multimode (https://gyazo.com/a6be2178b3168a452e7f0cf54dc84a70). Did you mean Mode not Node?

 

So what is the advantage of Multinode, faster than Single?

 

Are you saying Fiber channel has nothing to do with LC to LC cables? Or SFP?

 

[Lurick]

Singlemode has far greater distance than Multimode fiber and is generally used for long distance transmissions however it also tends to cost more compared to multimode fiber which is great for short distances and higher bandwidth application.

 

Fiber Channel is used for storage communication and has nothing to do with types of fiber or SFPs.

[lukesterboy]

50 minutes ago, Lurick said:

Singlemode has far greater distance than Multimode fiber and is generally used for long distance transmissions however it also tends to cost more compared to multimode fiber which is great for short distances and higher bandwidth application.

 

Fiber Channel is used for storage communication and has nothing to do with types of fiber or SFPs.

 

 

Ah ok. What i can't understand now is though all the connections. 

 

For example say i buy this switch, what connectors do I need. When i google the SFP connectors i see so many different types. Like 1000BASE-ZX, 1000BASE-LX/LH, 1000BASE-SX. What does this mean? Does it have to match the switch or as long as it's SFP it will fit in the switch? Also does the nm need to match up with the cables spec (wavelength)?

[Lurick]

So when you buy a switch it has SFP ports. 1000Base SFPs are for 1Gbit. The ZX is for very long range, LX/LH is Long range (single mode), and SX and short range (Multi Mode).

 

So if you aren't going for 100s of meters of distance then just getting 1000Base-SX SFPs are what you need. They take LC connectors regardless of Single or Multi mode. Just think of it this way, LC is long and skinny, SC is short and stubby.

 

So you'll need LC to LC cable if you're going from SFP to SFP.

[lukesterboy]

11 minutes ago, Lurick said:

So when you buy a switch it has SFP ports. 1000Base SFPs are for 1Gbit. The ZX is for very long range, LX/LH is Long range (single mode), and SX and short range (Multi Mode).

 

So if you aren't going for 100s of meters of distance then just getting 1000Base-SX SFPs are what you need. They take LC connectors regardless of Single or Multi mode. Just think of it this way, LC is long and skinny, SC is short and stubby.

 

So you'll need LC to LC cable if you're going from SFP to SFP.

1

Oh ok. What fiber connections connect into the back of a SFP  transceiver, just LC?

[Lurick]

1 minute ago, lukesterboy said:

Oh ok. What fiber connections connect into the back of a SFP  transceiver, just LC?

Correct, LC goes into SFP

SC is usually for X2 connectors and is 10Gig

[lukesterboy]

1 minute ago, Lurick said:

Correct, LC goes into SFP

SC is usually for X2 connectors and is 10Gig

 

Ok, this is a 10G switch and is SFP+. Does that still/can it still use LC and SFP+ transceiver or is it SC and SFP+ transceiver?

[Lurick]

Just now, lukesterboy said:

Ok, this is a 10G switch and is SFP+. Does that still/can it still use LC and SFP+ transceiver or is it SC and SFP+ transceiver?

 

Correct, that would be SFP and SFP+ transceivers and LC cables.

[lukesterboy]

1 minute ago, Lurick said:

 

Correct, that would be SFP and SFP+ transceivers and LC cables.

 

Ah ok. I understand it a bit more now. Is LC the only fiber connector that will connect into the back of an SFP transceiver or are there other connectors too? Also, could you just use this, rather than buying a LC to LC cable and 2 SFP transceivers?

[Lurick]

1 minute ago, lukesterboy said:

Ah ok. I understand it a bit more now. Is LC the only fiber connector that will connect into the back of an SFP transceiver or are there other connectors too? Also, could you just use this, rather than buying a LC to LC cable and 2 SFP transceivers?

Yah, that's basically and SFP with the cable built onto the end and uses copper instead of fiber but does the same thing.

[lukesterboy]

1 minute ago, Lurick said:

Yah, that's basically and SFP with the cable built onto the end and uses copper instead of fiber but does the same thing.

Ah ok. The cable looks thin. How do you know its copper does it say somewhere on that page that I'm not seeing it? Or for it to be fibre the modules and fiber cable have to be separate? Is copper enough for 10G and SFP+ connections?

[Lurick]

1 minute ago, lukesterboy said:

Ah ok. The cable looks thin. How do you know its copper does it say somewhere on that page that I'm not seeing it? Or for it to be fibre the modules and fiber cable have to be separate? Is copper enough for 10G and SFP+ connections?

That was my mistake. Those are actually fiber,

these are copper: http://www.fs.com/products/30849.html

[lukesterboy]

18 minutes ago, Lurick said:

That was my mistake. Those are actually fiber,

these are copper: http://www.fs.com/products/30849.html

 

Thought so, I came across those earlier, direct attach cables. Say i got a 10G SFP+ Switch and a PC that was 10M away. How do i know what SFP+ Module(Transceiver) to get? Since you talked earlier about all the Bases like ZX, LX/LH and SX. 10GBase has SR,LRM,LRM2,LR,ER40,ER,ZR,ZR100. What do all of these mean and is there a page where i can find all the meanings of these? Do pick the connector i want by distances and depending if i want singlemode or multimode?

[Lurick]

3 hours ago, lukesterboy said:

Thought so, I came across those earlier, direct attach cables. Say i got a 10G SFP+ Switch and a PC that was 10M away. How do i know what SFP+ Module(Transceiver) to get? Since you talked earlier about all the Bases like ZX, LX/LH and SX. 10GBase has SR,LRM,LRM2,LR,ER40,ER,ZR,ZR100. What do all of these mean and is there a page where i can find all the meanings of these? Do pick the connector i want by distances and depending if i want singlemode or multimode?

If you're going for 1Gig I would go for a 1000BaseSX with LC to LC multimode fiber.

If you're going for 10Gig you can either go 10Gig MM SFPs with LC to LC multimode fiber

-OR-

Get the fiber AOC that's 10M long or a sfp-h10gb-cu10m

 

A good explanation of all the different acronyms:

http://www.cisco.com/c/en/us/products/collateral/interfaces-modules/gigabit-ethernet-gbic-sfp-modules/product_data_sheet0900aecd8033f885.html

[leadeater]

8 hours ago, lukesterboy said:

First thing is can any connector be on any end of  Fiber patch cable. For example, does it have to be LC to LC or can it be anything like LC to SC, or can it only work some ways like, for example, I know LC to FC exists but does FC to SC for instance? Sorry for the bad explaining.

Yes you can have different connectors, common ones being: LC to FC, LC to SC-DC and LC to ST. Reason for this is it depends on what fibre patch trays you have. It's rather common for a lot of places to have older SC-DC fibre patch trays so they would use LC to SC-DC patch cables.

 

It is also important to note there are different fibre core sizes: OM1 (62.5/125), OM2 (62.5/125), OM3 (50/125), OM4 (50/125). OM1 and OM2 will typically be orange cables and OM3 and OM4 will typically be aqua. OM3 and OM4 supports higher speeds and longer distances.

https://en.wikipedia.org/wiki/Multi-mode_optical_fiber#Comparison

 

8 hours ago, lukesterboy said:

Next, do you have to have the block connector things, not sure what there called but the things that hold each fibre cable side by side on when you plug it into an SFP transceiver, on to plug it into an SFP transceiver?

Ah not sure what you are talking about? Photo or link will help.

 

8 hours ago, lukesterboy said:

Last, so a Fiber switch is known as an FC Switch (Fiber Channel Switch), can this Switch accept any Fibre connector assuming you get a SFP/SFP+ (not sure what one) transceiver on the end of the Fiber cable connector?

No as mentioned by @Electronics Wizardy Fibre Channel and an SFP/SFP+/QSFP+ Ethernet switches are different. They use different transport protocols, Fibre Channel vs Ethernet.

 

8 hours ago, lukesterboy said:

Can someone explain simply what is the difference between simple and multimode?

Going to be super lazy here since the wiki is rather good on the difference already. Basically Multimode = Cheaper, lower power and short distance.

Quote

The main difference between multi-mode and single-mode optical fiber is that the former has much larger core diameter, typically 50–100 micrometers; much larger than the wavelength of the light carried in it. Because of the large core and also the possibility of large numerical aperture, multi-mode fiber has higher "light-gathering" capacity than single-mode fiber. In practical terms, the larger core size simplifies connections and also allows the use of lower-cost electronics such as light-emitting diodes (LEDs) and vertical-cavity surface-emitting lasers (VCSELs) which operate at the 850 nm and 1300 nm wavelength (single-mode fibers used in telecommunications typically operate at 1310 or 1550 nm ^[3]).

https://en.wikipedia.org/wiki/Multi-mode_optical_fiber#Comparison_with_single-mode_fiber

 

 

[leadeater]

5 hours ago, lukesterboy said:

Thought so, I came across those earlier, direct attach cables. Say i got a 10G SFP+ Switch and a PC that was 10M away. How do i know what SFP+ Module(Transceiver) to get? Since you talked earlier about all the Bases like ZX, LX/LH and SX. 10GBase has SR,LRM,LRM2,LR,ER40,ER,ZR,ZR100. What do all of these mean and is there a page where i can find all the meanings of these? Do pick the connector i want by distances and depending if i want singlemode or multimode?

Direct attached SFP+ is a different beast all together. There are two kinds, Active and Passive. Passive is the most commonly used and supports slightly shorter distances to around 7m-10m. Active supports up to 15m.

 

With direct attached it's all in one, you don't have to worry about transceivers etc.

 

https://en.wikipedia.org/wiki/10_Gigabit_Ethernet#SFP.2B_Direct_Attach

[tt2468]

10 hours ago, ARikozuM said:

It helps with digestion. @Electronics Wizardy might be able to help out.

;_; nobody ever quotes me for this type of stuff

[ARikozuM]

Did somebody quote me? /s

 

@tt2468

In time, I'll learn what you're good at and I'll be sure to summon you... like a Caterpie...

[brwainer]

2 hours ago, leadeater said:

Direct attached SFP+ is a different beast all together. There are two kinds, Active and Passive. Passive is the most commonly used and supports slightly shorter distances to around 7m-10m. Active supports up to 15m.

 

With direct attached it's all in one, you don't have to worry about transceivers etc.

 

https://en.wikipedia.org/wiki/10_Gigabit_Ethernet#SFP.2B_Direct_Attach

In addition (this is for the OP) SFP+ DAC *cannot* be used on SFP ports. The original (1 gigabit) SFP specification doesn't have DAC in it, that was added with the (10gigabit) STP+ standard. So with the switch that was linked before, which only has SFP ports, you can't use DAC. Instead with SFP you can get modules with RJ45 ethernet ports on them. There is no such thing as a 10Gb SFP+ RJ45 module, that's why DAC exists. My understanding is that circuitry for 10Gb copper ethernet is too large and too power hungry at present to fit in an SFP module

 

8 hours ago, lukesterboy said:

Ah ok. I understand it a bit more now. Is LC the only fiber connector that will connect into the back of an SFP transceiver or are there other connectors too? Also, could you just use this, rather than buying a LC to LC cable and 2 SFP transceivers?

Every fiber SFP I have ever seen has LC connectors on it, because they are basically the only connectors that will fit on the end. But the connector makes no difference to the light - you can get patch cables with any combination of connectors.

[lukesterboy]

16 hours ago, Lurick said:

If you're going for 1Gig I would go for a 1000BaseSX with LC to LC multimode fiber.

If you're going for 10Gig you can either go 10Gig MM SFPs with LC to LC multimode fiber

-OR-

Get the fiber AOC that's 10M long or a sfp-h10gb-cu10m

 

A good explanation of all the different acronyms:

http://www.cisco.com/c/en/us/products/collateral/interfaces-modules/gigabit-ethernet-gbic-sfp-modules/product_data_sheet0900aecd8033f885.html

 

 

 

Ah ok. Kinda understand more.

14 hours ago, leadeater said:

Yes you can have different connectors, common ones being: LC to FC, LC to SC-DC and LC to ST. Reason for this is it depends on what fibre patch trays you have. It's rather common for a lot of places to have older SC-DC fibre patch trays so they would use LC to SC-DC patch cables.

 

It is also important to note there are different fibre core sizes: OM1 (62.5/125), OM2 (62.5/125), OM3 (50/125), OM4 (50/125). OM1 and OM2 will typically be orange cables and OM3 and OM4 will typically be aqua. OM3 and OM4 supports higher speeds and longer distances.

https://en.wikipedia.org/wiki/Multi-mode_optical_fiber#Comparison

 

Ah not sure what you are talking about? Photo or link will help.

 

No as mentioned by @Electronics Wizardy Fibre Channel and an SFP/SFP+/QSFP+ Ethernet switches are different. They use different transport protocols, Fibre Channel vs Ethernet.

 

Going to be super lazy here since the wiki is rather good on the difference already. Basically Multimode = Cheaper, lower power and short distance.

https://en.wikipedia.org/wiki/Multi-mode_optical_fiber#Comparison_with_single-mode_fiber

 

 

4

 

Ahh ok. I see.

 

Thanks for telling me about the speeds (fiber core sizes) (OM1,OM2 etc).

 

As for the thing im talking about. It's basically the house holding each connector together. Is it removable on some connectors like SC? Is it removable on LC as well?

 

Here is the picture i mean, for the houseing around the LC.

 

 

Oh is fiber channel direct fibre (LC connectors into a switch), i thought it uses SFP modules still...

14 hours ago, leadeater said:

Direct attached SFP+ is a different beast all together. There are two kinds, Active and Passive. Passive is the most commonly used and supports slightly shorter distances to around 7m-10m. Active supports up to 15m.

 

With direct attached it's all in one, you don't have to worry about transceivers etc.

 

https://en.wikipedia.org/wiki/10_Gigabit_Ethernet#SFP.2B_Direct_Attach

 

 

 

I see. Sounds...um...fast

[brwainer]

6 hours ago, lukesterboy said:

As for the thing im talking about. It's basically the house holding each connector together. Is it removable on some connectors like SC? Is it removable on LC as well?

 

Here is the picture i mean, for the houseing around the LC.

 

You can (carefully!) remove and reattach that clip that hold the two together - I've had to do it a few times to resolve duplex mismatch issues (when the TX and TX are connected together, and the RX and RX together as well). I'm not really aware of a situation where you would want to keep them seperate, but there could be one

[lukesterboy]

8 hours ago, brwainer said:

You can (carefully!) remove and reattach that clip that hold the two together - I've had to do it a few times to resolve duplex mismatch issues (when the TX and TX are connected together, and the RX and RX together as well). I'm not really aware of a situation where you would want to keep them seperate, but there could be one

Fair enough.