Network Setup Help

[danb35]

What part of "and the same wavelength" are you having trouble understanding?

 

[Etorix]

Yes.
SR 850nm MMF on one end -> SR 850 nm MMF on the other end (each with its own vendor coding; "generic" should be fine on Mikrotik's end)
LR-10km 1310 nm SMF on one end (because SMF is a lot cheaper than MMF for duplex LC) -> LR-10 km 1310 nm SMF
…and you can have both next to each other.

 

[Patrick M. Hausen]

@Etorix don't you need a dampening element if you connect two LR SMF modules over a short distance?

 

[Fastline]

What part of "and the same wavelength" are you having trouble understanding?

I think i got it now with the help of your last post and also of @Arwen

To recap, the same wavelength means that both the NIC and switch end should have the SR/LR optics right?

 

[Etorix]

@Patrick M. Hausen Maybe… I admit I have never used SMF (or LR modules) so far; I made up an example with different protocols and wavelenghts for illustration purpose.

 

[Fastline]

Yes.
SR 850nm MMF on one end -> SR 850 nm MMF on the other end (each with its own vendor coding; "generic" should be fine on Mikrotik's end)
LR-10km 1310 nm SMF on one end (because SMF is a lot cheaper than MMF for duplex LC) -> LR-10 km 1310 nm SMF
…and you can have both next to each other.

Cool cool. I got it.

My next question is can i use the SFP+ module in an SFP28 port (Switch) and SFP28 NIC?

 

[Fastline]

@Etorix don't you need a dampening element if you connect two LR SMF modules over a short distance?

Umm, as far as i'm aware, the LR optics is used for long distances. Can they also be used for short distance? And if using the LR optics, do they generate any kind of noise which needs to be damped?

 

[Patrick M. Hausen]

Maybe… I admit I have never used SMF (or LR modules) so far; I made up an example with different protocols and wavelenghts for illustration purpose.

OK, so I did not miss anything. Modules with an output power to drive a kilometre of fibre without any intermediate repeater/amplifier overload the receiving end if connected over a couple of meters.

So @Fastline in general you want short range multimode for local connections.

 

[Ericloewe]

@Etorix don't you need a dampening element if you connect two LR SMF modules over a short distance?

For 10GBase-LR, the minimum run specified is something like 1.5 m. That means most practical installations are fine without attenuators.

To recap, the same wavelength means that both the NIC and switch end should have the SR/LR optics right?

Same type of optics, yes. There are very weird types once you start digging deeper and once you move to QSFP. For standard SFP/+/28, stick with the basic SR or LR and you should be fine. For QSFP+/28, it will depend on your cabling situation.

Is this AOC?

QSFP breakout cables are available in basically all types: plain fiber cable with high density connector on one end and duplex LC pairs on the other, Active Optical Cables, and Direct Attach Copper. The Mikrotiks support breakout, but not all devices do. Always double-check.

Umm, I'm not sure about that either. HPE and Dell require their own modules for the link. But as far as I'm aware, Mikrotik doesn't have such special requirements.

Mikrotik doesn't vendor lock. HPE is a massive pain, depending on whether you have legacy HPE stuff or Aruba stuff. Dell is just Dell, so at least it's easier.

Will this all work correctly? I'm concerned about the compatibility. Can i use like this (interconnecting 10G and 25G) or both the switch end and NIC end has to be the same module must have the same wavelength and speed?

Most 25 GbE NICs and switches can do at least 10 Gb/s and 25 Gb/s. However, SFP modules often do not. Unless you have a good reason to do otherwise, use the lowest common denominator SFP module or cable, e.g. 10GbE to connect a 10GbE to a 25GbE device.

 

[Fastline]

OK, so I did not miss anything. Modules with an output power to drive a kilometre of fibre without any intermediate repeater/amplifier overload the receiving end if connected over a couple of meters.

So @Fastline in general you want short range multimode for local connections.

Yes, the range is less than 50 meters. Definitely going with the SR, MMF.

 

[Fastline]

Same type of optics, yes. There are very weird types once you start digging deeper and once you move to QSFP. For standard SFP/+/28, stick with the basic SR or LR and you should be fine. For QSFP+/28, it will depend on your cabling situation.

Hmm. Yes, its very complex. Hopefully, i would be able to get it done easily with your support guys. Thank you everyone so far!

QSFP breakout cables are available in basically all types: plain fiber cable with high density connector on one end and duplex LC pairs on the other, Active Optical Cables, and Direct Attach Copper. The Mikrotiks support breakout, but not all devices do. Always double-check.

Oh, another learning for me :)

Mikrotik doesn't vendor lock. HPE is a massive pain, depending on whether you have legacy HPE stuff or Aruba stuff. Dell is just Dell, so at least it's easier.

Yeah, i have heard too many scary story. Afterall, that's another way to make some extra $$$$ buy implementing the vendor lock, forcing customer to buy the vendor compatible module only.

BTW, the switches involves vendor locking, do they require the vendor compatible module at the switch end or at the NIC end too?

Most 25 GbE NICs and switches can do at least 10 Gb/s and 25 Gb/s. However, SFP modules often do not. Unless you have a good reason to do otherwise, use the lowest common denominator SFP module or cable, e.g. 10GbE to connect a 10GbE to a 25GbE device.

Yes, yes. I'll need to draw a diagram soon.

Thank you so much!

 

[Etorix]

BTW, the switches involves vendor locking, do they require the vendor compatible module at the switch end or at the NIC end too?

The switch or the NIC passes electrical signals to the module; vendor lock may be involved in this communication (i.e. equipment refuses to communicate if the partner does not first show a suitable identity card).

The module then converts the electrical signal to optical, at a given wavelength and with a given protocol (SR, LR). Over the fibre, there's no vendor.

The receiveing module takes the optical signal it expects (wavelength, protocol) and converts it to electrical, which it passes to the NIC or switch—possible vendor lock.

 

[Fastline]

The switch or the NIC passes electrical signals to the module; vendor lock may be involved in this communication (i.e. equipment refuses to communicate if the partner does not first show a suitable identity card).

The module then converts the electrical signal to optical, at a given wavelength and with a given protocol (SR, LR). Over the fibre, there's no vendor.

The receiveing module takes the optical signal it expects (wavelength, protocol) and converts it to electrical, which it passes to the NIC or switch—possible vendor lock.

Gotcha!

 

[Fastline]

Guys, although i'm about finalize the network parts, i had a quick question.

I was checking the Intel NIC datasheet to get a compatible module and i notied a few things which i would like to ask.

1. Does End of Life here mean the optic module is discontinued?
2. What does Single Rateand Dual Rate mean here?
3. What does Extended Temp mean here? And what are the standard Temp?

Beside this, i have a few more questions:

- Do these optic module generate a lot of heat? Ad does the Fiber Cable also heats up during the transmission?
- I read somewhere that if there is rise in temperature, there can be signal degradation and it can stop working. Is that true?
- What do you guys suggest regarding the optic brand? Finsar or Broadcom?

Thanks

 

[danb35]

- What do you guys suggest regarding the optic brand? Finsar or Broadcom?

I suggest compatible optics from fs.com. Otherwise, used Finsair from eBay can be a good choice, as I've heard.

Ad does the Fiber Cable also heats up during the transmission?

The power output from the modules isn't enough to measurably heat up the fiber.

 

[Ericloewe]

Does End of Life here mean the optic module is discontinued?

Yes, for certain values of "discontinued".

2. What does Single Rateand Dual Rate mean here?

Look at the type column. One or two speeds (1 Gb/s and 10 Gb/s; 10 Gb/s and 25 Gb/s).

3. What does Extended Temp mean here? And what are the standard Temp?

Well, a wider range of specified ambient temperatures. This is not a meaningful concern for most people.

Do these optic module generate a lot of heat?

Some, of course. How much will depend on the specific module.

Ad does the Fiber Cable also heats up during the transmission?

Not to any extent measurable outside of a high-end metrology lab.

I read somewhere that if there is rise in temperature, there can be signal degradation and it can stop working. Is that true?

As with all electronic devices, the transceivers must operate within a reasonable range of temperatures, yes.

What do you guys suggest regarding the optic brand? Finsar or Broadcom?

You're overthinking this. Buy whatever from the list. Used or new. Or buy something explicitly listed as compatible. Or don't and tell the driver to accept non-validated SFP modules.

 

[Fastline]

I suggest compatible optics from fs.com. Otherwise, used Finsair from eBay can be a good choice, as I've heard.

The power output from the modules isn't enough to measurably heat up the fiber.

Thanks mate.

 

[Fastline]

Yes, for certain values of "discontinued".

Look at the type column. One or two speeds (1 Gb/s and 10 Gb/s; 10 Gb/s and 25 Gb/s).

Well, a wider range of specified ambient temperatures. This is not a meaningful concern for most people.

Some, of course. How much will depend on the specific module.

Not to any extent measurable outside of a high-end metrology lab.

As with all electronic devices, the transceivers must operate within a reasonable range of temperatures, yes.

You're overthinking this. Buy whatever from the list. Used or new. Or buy something explicitly listed as compatible. Or don't and tell the driver to accept non-validated SFP modules.

Thank you for answering all my questions. Highly appreciated!