Network Switch with Optical Input

[jabbr]

Even the best of switches will have 'collisions' if the combined traffic destined for a certain port exceeds the capacity of that port. A decent switch will have a larger per-port queue allowing it to absorb short bursts of traffic. However, audio bandwidths are low enough that even a basic switch rarely struggles.

 

That's a better way to say what I meant Point being that a reasonable switch should be able to provide full bandwidth to an audio application.

[jabbr]

Well, as I read @Axiom05's suggestion he was saying run fibre from the main network to a "HiFi" switch where he would connect both the NAS and the player. Now if the reason for using fibre is to isolate noise from the NAS reaching the player, then if you connect both to a switch then you are not isolating them.

 

To clarify: if you connect both to a *copper* switch, you are not isolating, but if everything is connected by fiber to an SFP switch, then there is isolation.

[Albrecht]

I'm not sure about that, a good switch doesn't have 'collisions' whereas some home routers are bandwidth limited.

 

I first tried a pair of FMCs, heard a significant improvement and have moved to a complete optical network. All of my music related machines have optical NICs (SFP+). My music switch has 8 SFP ports and is powered by LPS. I do have a 'legacy' copper network for things like IPMI and some legacy copper connections, also for our video 'TV' and this copper switch has a 10 fiber optic uplink to the main fiber switch.

 

... but music is distributed by fiber

 

Thanks for all the clarifications. I was originally considering something like running two 8 port switches connected via 1 fiber cable, (6 GB RJ45 ethernet with 2 multimode fiber). But then I thought it would be much cheaper to just link two MCs directly from the NAS to the NAA, - even though two short RJ45s are required.

 

 

Your NAA has a fiber NIC?

[Albrecht]

One thing, its usually best to have identical SFP modules at each end - so a pair of TP-Link MC200 would be fine, but if you have a switch with built in SFP module best to use a TP-Link MC220 plus a SFP module. This is for reliability and compatibility rather than any "sound quality" issues.

 

For isolation purposes the best arrangement is a single media converter connected directly to your HiFi PC (or streamer). If you add a switch the the HiFi end then you are undoing any isolation.

 

 

Hi,

Thank you for this! So, - if I have an RJ45 network, - and I attach one MC (via a short rJ45 of course) directly to the NAS and the other MC at the audio rack plugged into the NAA, - I will be providing isolation?

[jabbr]

Your NAA has a fiber NIC?

 

Yes, the ASUS Q1900M has an Intel x520 NIC. This card also has firmware to do direct iSCSI boot, so my NAA has no disc drive or SSD.

 

I wouldn't advise connecting two copper (RJ45) switches via a fiberoptic link, not sure that would accomplish enough to be worth it.

[Audio_ELF]

I was more concerned about isolating my music system from the rest of the house network "noise." You are correct about any noise from the NAS and if this was a concern I could run another stretch of FO from switch to computer/music server. Unfortunately there will always be some copper and a device, i.e., adapter, between FO and computer unless the computer also has FO input.

 

Thank you for the reply. I am by no means an expert in networking but I thought using a fiber connection eliminates noise. If so it stands to reason that it wont matter having a switch???

 

Well if you go...

Router --fibre--> switch --cat5--> NAS + player

You eliminate any noise passed down the copper from the router and other devices on the router, but you don't eliminate noise from the NAS.

 

If you go...

Router --cat5--> NAS (+) --fibre--> player

Then you eliminate all noise passed from all devices on the network.

 

It all depends what you are trying to avoid.

 

In addition most people want the NAS outside the listening room.

[davide256]

Well if you go...

Router --fibre--> switch --cat5--> NAS + player

You eliminate any noise passed down the copper from the router and other devices on the router, but you don't eliminate noise from the NAS.

 

If you go...

Router --cat5--> NAS (+) --fibre--> player

Then you eliminate all noise passed from all devices on the network.

 

It all depends what you are trying to avoid.

 

In addition most people want the NAS outside the listening room.

 

That doesn't make sense... a NAS is not intended to route packets and you are direct connecting the NAS to the player. How are you getting IP packet routing between NAS and player?

[jabbr]

Firstly it's not necessary to use the same SFP on each end. Many brands of SFP switches and NICs require specific SFPs so it's not possible in the general case to do this.

 

It is much cleaner to use an SFP switch and connect any copper/RJ45 connections to this switch through the use of FMCs.

 

So I would do:

 

Router -> FMC -> SFP switch ->

(FMC) -> NAS

(FMC) -> player

 

Where FMCs are only needed if the NAS or player doesn't itself have a direct SFP based connection

[davide256]

Firstly it's not necessary to use the same SFP on each end. Many brands of SFP switches and NICs require specific SFPs so it's not possible in the general case to do this.

 

It is much cleaner to use an SFP switch and connect any copper/RJ45 connections to this switch through the use of FMCs.

 

So I would do:

 

Router -> FMC -> SFP switch ->

(FMC) -> NAS

(FMC) -> player

 

Where FMCs are only needed if the NAS or player doesn't itself have a direct SFP based connection

 

Your solution makes sense as the NAS and player are layer 2 connected to the SFP switch and get layer 3 routing over layer 2 connection to the same SFP switch. And with all connections over optics you have electrical isolation of router, switch, NAS and player. I'll have to cost this out as an upgrade from the AQ Pearl Ethernet cables I have now.

[davide256]

scanning Amazon, it looks like this requires

 

1. SFP switch ~$200

2. 3 SFP/GBICs ~$150

3. 3 optic fiber pairs ~$45

4. 3 FMC's ~$300

 

or about $700. Any suggestions on how to bring this cost down?

[jabbr]

scanning Amazon, it looks like this requires

 

1. SFP switch ~$200

2. 3 SFP/GBICs ~$150

3. 3 optic fiber pairs ~$45

4. 3 FMC's ~$300

 

or about $700. Any suggestions on how to bring this cost down?

 

http://www.ebay.com/ulk/itm/262037355221

http://www.ebay.com/ulk/itm/221998586642

TP-LINK MC220L Gigabit Media Converter, 1000Mbps RJ45 to 1000Mbps SFP slot supporting MiniGBIC modules, chassis mountable https://www.amazon.com/dp/B003CFATL0/ref=cm_sw_r_cp_awd_Iz9Owb2A9BJTT

[davide256]

Thanks, $250 is a much better number :<)

[Audio_ELF]

That doesn't make sense... a NAS is not intended to route packets and you are direct connecting the NAS to the player. How are you getting IP packet routing between NAS and player?

Sorry my description wasn't very good...

 

Ideally (to my mind and because you are aiming to isolate due to EMI not network isolation) you should connect...

to your router (or a switch connected to router): (1) your NAS, (2) the FMC (fibre media converter)

...then a length of fibre from one FMC to a second located near your player, and a short cat 5 to the player.

 

Pretty much as jabbr stated only I can't see the need of using fibre to connect the NAS.

[Audio_ELF]

Firstly it's not necessary to use the same SFP on each end. Many brands of SFP switches and NICs require specific SFPs so it's not possible in the general case to do this.

As a theoretical reply, I agree it shouldn't be necessary to use identical SFP at each end, but I've found that there can be compatibility issues if you don't use identical ones. Probably not significant in small home installations but over larger commercial projects it can be an issue.

[Audio_ELF]

9 Ports Gigabit Ethernet Optical Fiber Switch with 8 SFP Ports and 1 1000M RJ45 | eBay

Cisco GLC SX mm Tranceiver Modules Genuine Cisco | eBay

TP-LINK MC220L Gigabit Media Converter, 1000Mbps RJ45 to 1000Mbps SFP slot supporting MiniGBIC modules, chassis mountable https://www.amazon.com/dp/B003CFATL0/ref=cm_sw_r_cp_awd_Iz9Owb2A9BJTT

Just to note, that TP-Link FMC won't work with most dedicated streamers (rather than a PC based) as most are 10/100 rather than supporting Gbit networking.

[Axiom05]

Just to note, that TP-Link FMC won't work with most dedicated streamers (rather than a PC based) as most are 10/100 rather than supporting Gbit networking.

 

This is a good point that I overlooked, just assumed everything was gigabit these days. Luckily it looks like the Aurender units (possible future purchase) are gigabit.

[Axiom05]

Ideally (to my mind and because you are aiming to isolate due to EMI not network isolation) you should connect...

to your router (or a switch connected to router): (1) your NAS, (2) the FMC (fibre media converter)

...then a length of fibre from one FMC to a second located near your player, and a short cat 5 to the player.

 

Pretty much as jabbr stated only I can't see the need of using fibre to connect the NAS.

 

This makes sense. If you are not going all fiber as jabbr has described, just linking a fiber between your switch & streamer via FMC's is probably the most cost-effective method to give some isolation. NAS is probably OK just connected to switch via ethernet. Additional fiber is probably not worth the added cost unless one goes "whole hog."

[jabbr]

Just to note, that TP-Link FMC won't work with most dedicated streamers (rather than a PC based) as most are 10/100 rather than supporting Gbit networking.

 

Good point, the "Optical Network Config" thread discusses all these issues, and it would take a lot of work to replicate all these recommendations here. Worth reading before purchasing stuff.

[jabbr]

As a theoretical reply, I agree it shouldn't be necessary to use identical SFP at each end, but I've found that there can be compatibility issues if you don't use identical ones. Probably not significant in small home installations but over larger commercial projects it can be an issue.

 

Please post any incompatibilities you know of! (Optical Net Config thread). Will save us lots of time/money. The actual SFPs that I use are posted there.

[jabbr]

This makes sense. If you are not going all fiber as jabbr has described, just linking a fiber between your switch & streamer via FMC's is probably the most cost-effective method to give some isolation. NAS is probably OK just connected to switch via ethernet. Additional fiber is probably not worth the added cost unless one goes "whole hog."

 

Sure, of course my NAS has a dual 10g fiber connection, but that's just me Also the fiber NICs offload CRC checks, and connect directly to Xeon cache, can offload iSCSI etc. and so make the network faster.

[mansr]

Sure, of course my NAS has a dual 10g fiber connection, but that's just me Also the fiber NICs offload CRC checks, and connect directly to Xeon cache, can offload iSCSI etc. and so make the network faster.

 

That's all nice but hardly relevant for audio streaming.

[jabbr]

That's all nice but hardly relevant for audio streaming.

 

Again, just me, it helps me to listen to all the voices in my head at the same time...

 

Seriously though, correct, not needed for audio, but for video, particularly processing ...

[mansr]

Again, just me, it helps me to listen to all the voices in my head at the same time...

 

Seriously though, correct, not needed for audio, but for video, particularly processing ...

 

Video streaming no, video editing yes, absolutely.