Melco S100 Ethernet Switch Measurements

[R1200CL]

14 hours ago, plissken said:

 

LOL. I got a kick out of that post... Some how the eR or other audiophile switches are somehow the gold standard.

 

I've got $8000 just burning a hole in my pocket to give away.

Should I understand an eye pattern diagrams is the measurement you looking for when it comes to the etherRegen?

Would that make you confident that the etherRegen does what it says it it will do ?

 

If so, can’t we use some of that $8000 and have a lab do such a measurement for us ?

Where to send the switch ? Expected cost ?

[R1200CL]

On 9/27/2020 at 6:19 PM, jabbr said:

further discussion on the "Optical Network Configurations" thread which exists for exactly these issues

I’ve start reading from page 60. That’s more than a year back. Good tread. 

So I’ve learned one should probably go for Finsair single mode fiber and avoid the VCSEL laser.

 

Not sure if SPF+ or SPF28 is preferred. The latter maybe more future proof. I would also expect more expensive. Anyway cage is equal, so you can upgrade modules later. 
 

I’ve also noticed some had problems with RJ45 SFP in general, but the Mikrotik ones seems to bee good. 
 

Cables are cheap, and most singel mode cables seems to be OK. There is no explanation if the differences OM matters. So probably not. 
 

How easy it is to cut and replace connectors on cables hasn’t been discussed. (I would need to do for behind wall installation). I like to see a post about that. Does there exist fiber wall plugs. 
 

Looking at eBay and all the different variations of SFT modules being offered, it’s a challenge to find exact matching numbers in Finsair model chart. And then be sure you get what you want. So many may find this challenging. 
 

Prices vary a lot. But if you like to purchase new modules, they are expensive. I can see price can be an issue, even there are examples of reasonable priced items. As, or if, popularly of fiber raise, used version of the preferred modules probably will be hard to get. 
 

I can see a challenge and a support issue for manufacturers who like to standardize on SFP+/SFP28.

We could probably make an audiophile selection chart for such modules. 

May @jabbr you can make a good summary in your tread what’s we learned so far and status. 
A start for an informative article here at AS on fiber for beginners. 

 

[R1200CL]

On 9/17/2020 at 5:24 PM, plissken said:

1. Switches do have buffers and you can manipulate these with various commands to affect priority que.

2. A buffers sole job is to establish a clock domain boundary for systems that have different timings.

3. My buffer is 1GB of RAM on my JRiver based system. This is why I always point out 'correctly designed/engineered systems'.

4. Even a buffer of a single MB is enough. But what that does is keep the receiver PHY in play longer over the duration. I prefer as much wire speed as possible and buffer up front.

I started reading this tread from the beginning. 
Since I have two Cisco switches. One 2960G and one SG300-20. 
 

1. Can I manipulate these buffers in any way you describe in my switches ?

2. It may be a bit more complicated as discussed here. Also buffers has jitter. 
3. That’s a difference buffer I would say, but yes still a buffer. It’s task is not related to switch and network. 
4. Buffer size may also be determined by speed. Huge buffers may require I/O logic, causing new issues. I think also number of ports would matter in the buffer design. 
 

I found this as an example:

The general rule of thumb is that you need 50ms of line-rate output queue buffer, so for for a 10G switch, there should be around 60MB of buffer. This is particularly important if you have a 10G host sending to a 1G host across the WAN. But there are a number of switch design issues that make it hard to quantify exactly how much buffering is actually required.

 

Here is another problem with buffers in network being to huge. 
https://wiki.geant.org/display/public/EK/Buffer+Bloat

 

What is your advice when it comes to flow control ?

I think this is a way to avoid  a buffer fill up, so put on should on should “slow” down the amount of data being sent. 
 

About jitter and phase noise noise in John’s white paper.

I think the figures used in this document illustrates what it’s about.

https://www.ti.com/lit/an/slyt379/slyt379.pdf?ts=1602856162664

 

I also find this document a bit educating. At least I now almost understand the jitter numbers in Finisar data sheets. 
https://www.idt.com/eu/en/document/whp/theroleofjitter-intimingsignals
 

 

 

 

 

 

[R1200CL]

15 hours ago, Miska said:

 

Especially if you have any small NAA devices or similar, you will certainly want to have it (802.3x) enabled. It can help a lot even with regular desktop computers.

 

Thanks.

 

You or @plissken 

 

Is there in general any other settings you guys would recommend on a managed switch. 
My user guide is 586 pages 😀

 

My Cisco SM300-20 is hided in a closet/shed and I connected the uplink port to a Cisco WS-C2960G-8TC-L  in living room. ( >etherRegen > opticalRendu). That switch has a 360 pages manual. 

 

I haven’t yet accessed my 2960G, but is there any settings I ought to do there as well. 
Like in addition add flow control on the single port for streaming. 

 

Instead of building separate network (from your router) in a belief of that should in any way help, can some tricks be done in managed switches to obtain something equal ?

 

Quite often, like me, people have server one place away from audio, so I was thinking in a direction where some sort of QoS or other settings could have an effect. I read about enabling jumbo frames, which I think isn’t helpful for audio, but maybe for video, just to mention one setting. Link aggregation is another setting that may a positive effect? What else can be tweaked?

 

I understand there may not be a definitive answer to this, so an answer in direction, you wouldn’t do anything harm, is more what I’m looking for. 

I’m planning, as a test to move my SonicTransporter with HQPlayer embedded to living room 2960 switch. Maybe with an optical Module in between, which then would have to use the uplink port. 
 

Do you think there in theory is an advantage using same switch between endpoint and HQPlayer/Roon server? (in general in order to obtain less other network traffic between those two). 

 

What do I achieve, if anything, by using uplink port between those two switches?

 

 

[R1200CL]

 

[R1200CL]

16 hours ago, Miska said:

 

HQPlayer uses QoS, so if you use HQPlayer with NAA, you need at least:

802.3x Flow Control

802.1p COS / QoS

802.3az EEE (sorta optional, although you'd want it to minimize noise)

 

And on Cisco switches you need to set multicast to "Forward Unregistered", example like this:

 

And use IPv6 if possible instead of IPv4.

 

I like to try this on my switch. Maybe we need a tread about how to/suggested setting for HQPlayer in managed (Cisco) switches. 

Or maybe it’s better to do PM .
 

Here is some screenshots of menu is my switch as now before changing anything. 

About QoS

Should I use basic mode or advanced?

Should I enable the global setting?

I noticed lag can be used instead of port. Is it a god idea to use lag ?

I think I probably can use this guide to configure LAG.
 

 

[R1200CL]

If I understand the term VLAN correctly, one can think of this a separate network between (in my case) your Roon/HQPlayer server and your endpoint. 
 

So within that virtual network, I can apply various QoS and settings only relevant between those two (or several) ip addresses or those participating devices in that virtual network. 
 

So one port can serve several VLAN’s 😀

Really hope I got this right?

[R1200CL]

18 minutes ago, ASRMichael said:

You can have thousands of VLAN’s on one port if you want. 

So if I add my Qnap to a VLAN consist of opticalRendu and SonicTransporter, will I then be able to access the Qnap from my PC ? (Probably not). 

Is the solution then to create another VLAN that includes the Qnap, PC etc. ?

 

I would also need at lest two VLAN’s for my iPad as well ?

(One accessing Roon and at least one everything else).