Audio Network Config Discussion Continued

Mike, part of my education was in Marine Biology - research ships are certainly an interesting environment.

Trying to differentiate pA signals in an instrument designed for a normal terrestrial lab when you're not that far from a marine radar installation is, well, challenging!  And making sure it doesn't get broken / stomped on / shorted by sea water / just generally corroded to uselessness, is almost as hard.

Hopefully this may be the final draft...

https://drive.google.com/file/...NVk/edit?usp=sharing

I've incorporated most of the comments and added

A sections on PLAs

An appendix for Cable Management

Mike,

I tried to get a better image of the RJ45 shield, but I don't really have suitable lighting for so small a subject, and flat reflective surfaces are notoriously difficult to show well, so I've added a comment to draw attention to it.

Simon,

I've reversed the use of the transmitter tower image, revised all the diagrams as suggested, and included the PLAs in the list of undesirables.

Many thanks to those who have contributed their comments to help improve this - the changes have been very beneficial.

.......  still recon the use of "right angled" is confusing

why not change "right angled" to "male to female",  that is the real description of the adaptors design principle, not right angled

I take the point, but I've never seen a straight male to female 'straight through' coupler (and I don't know why anyone would make a 'straight through' one (rather than crossover) - it would just be a very short extension cable!).

touche - your point taken

OK maybe the 45 degree adaptor I found is so hard to find, it might be better left out.  

I have to say its a little gem for tidying up cable entry

45°?  Ooh! Kinky!

45 degree brain fade   delayed effects of that Pinotage

........  back to business - I read the paper again & am concerned about the use of the "router" word.  My understanding of a hub & router disagrees with your paper - I think your "router" should be changed to HUB

I've done some cross checking on www & all I've found agrees with my understanding. Its clear there is a lot of confusion over this. Both are significantly different & it seems to me that correct terminology is misused a lot around home IT work & I think it deserves some clarification inserted into the paper.

My understanding is as follows ............ 

Hubs are typically supplied by ISP’s & enable connection of a simple network.

A hub can't identify the source or intended destination of the information it receives & sends traffic to all of the devices connected to it, including the one that sent it. Additionally a hub can’t send & receive at the same time & together with the whole network distribution of traffic, it makes them slower than switches & overload with low SQ is a potential problem with NAS based music.

Switches are specifically designed to direct traffic around a network.  Whilst they appear to work the same way as hubs, they are smarter & communicate with only the device(s) they are programmed for. Additionally they send & receive at the same time & are therefore faster than hubs.

Unmanaged switches “learn” the MAC addresses of the devices they are to communicate with as part of their initial switch on procedure. 

Managed switches are user programmed to communicate to specific MAC addresses.

Routers have more capability than hubs or switches & are programmed to direct traffic between networks. They are used with split networks and/or many devices on a network & access to the Internet using one modem.

They are more expensive than switches & hubs & are not supplied by ISP's.

Thanks Mike,  I both agree and disagree, at the same time

I believe that the things supplied by the ISPs are rather more sophisticated than you are suggesting.

In addition to the LAN hub, they incorporate SPI Firewalls, a 2 port Router (with Network Address Translation tables) to forward the WAN targeted traffic to the WAN Terminal Adapter and separate it from the LAN traffic. Via the TA the router part can forward appropriate packets to addresses on different subnets on the WAN (which a switch cannot do, and a hub is so stupid it always does!).  True, these are only two port functions (LAN or WAN), but in my book still classify it as a router.

On the LAN side, yes it's a hub, but were it only a hub and a TA, then all the internal network traffic would also be sent to the TA and onto the WAN.

Consider it as

Gigabit Ports

WiFi port

<>

n-port LAN Hub

<>

2 port Router

<>

Firewall

<>

WAN Terminal Adapter

Does this make sense to you?

I said I both agree and disagree, at the same time:

Yes it's hub for the LAN

but it's a router for the link between the LAN and the WAN.

Sorry Huge,  I disagree on your differentiation 

I see the differentiation of a router as as inter-network capable & that means its needs to be programmable to do that

A hub as supplied by ISP's has no such ability.  

Such a router (my interpretation) has the same switch packet handling ability as a switch & installing a switch to make a router work better as your paper shows does not make sense. 

It does make perfect sense when done with a hub. 

ISP hubs have various WAN/LAN versions - with a WAN connection & others integrated.

Most ISP devices include security such as firewall

Switches do not

Routers (my interpretation of router) have security

Finally based on my experience with my own ISP hubs (plural), my sons (another make) & yet another with a neighbour,  they are far from sophisticated,  almost unfit for purpose I would suggest. 

Mike,

"inter-network capable", exactly what they do:  From the internal LAN to the external WAN.  These are different IP address spaces.

All the ISP supplied devices I've set up recently do also have rudimentary security functions (some very old ones didn't).  Hubs don't include security functions, but as you say routers often do.

In terms of sophistication, they are more sophisticated than mere hubs.

In terms of fitness for purpose, they will connect one or more computers to the WAN.  This is usually the defined purpose as far as the ISP is concerned; anything else (such as home networking) is a secondary benefit.

Gents

A 'hub' is often used in the context of consumer home network components to describe a device which acts as a communications hub- such as to centre and attach one's home network to the internet. ie HomeHub. Typically a 'hub' will have a basic broadband router, wifi and switch.

However in IT networking terms a network hub is a very specific device which  allows you to share a network segment such that only ONE device can transmit or receive at any one time. This is different from a network switch which allows multiple devices to transmit and receive on a network segment at one time.

Hubs are largely obsolete for home use now as most consumers use switches - hence why the word 'hub' has been adopted for consumer broadband routers etc without causing to much confusion.

However in commercial networks network hubs are still occasionally used to allow network sniffing and monitoring on a temporary basis. This can be helpful when diagnosing and monitoring home networks as well if you only have basic equipment.

Simon

Simon,

So in essence you're saying that the word 'Hub' in the context of home networking is often used to describe a 'Consumer Broadband Router'

So, in the context of home networking, we're both right!

BT use the term Hub, TalkTalk use the term Router.

I wonder which term is more commonly use amongst all the ISPs?

Huge - yes though the term for consumer home broadband router is often compounded with another noun such as Virgin SuperHub or BT HomeHub - perhaps to stop issues with trade descriptions as they are not strictly network hubs..... and of course its easier to trademark such a term.

But theses devices are usually more formally a combined basic broadband modem and router, LAN switch,  wifi access point and software firewall.

Simon

PS The term Hub for the home precedes general internet access - and some of us were discussing such terms with futuristic home networks back in the very late 80s

Thanks Simon,

On that basis I think I'll stick with the more generic term 'Broadband Router' as it's clear from the diagram to what I am referring.

I can't explicitly cater for customers of all the ISPs that use 'SomethingHub' type names.  If I use the term 'Hub', customers of those ISPs that use the term 'Router' may think this only works with 'Hubs'.  This is componded by the marketing hype of both BT and Virgin which appears to imply that their devices are so much more capable than those provided by other ISPs.  This may cause some consumers of other ISPs to actually believe the hype, and hence think that their mere 'router' won't do the job.

Incidentally Simon, before I installed a separate switch, the network traffic from my computer (e.g. backup NAS to computer) seemed to also appearing at the Ethernet port of the ND5, so it appears that the LAN side of my broadband router was behaving like a network hub rather than like a switch.  On the other hand I didn't inspect the traffic, so it could have been status updates from the media server, but superficially it appeared to have the same pattern as the activity of the PC NIC.

Huge

Agree on your generic and correct term 'Broadband router'

As far as the broadband router acting as a network hub - I doubt it - if you tell me make and model I can confirm - but you were probably seeing broadcast and ,multicast traffic - or the LED flashing was simply aggregated usage on all ports.

Simon

I'll have a good read of this when I get a chance Huge, and see if it makes sense to a non tech trained person like myself.

Looks really good.

It brought a smile to my face when I noticed the parts that you mark as Warning controversial ! 

Wise statement 

It's OK it's behind a switch now and "All's Quiet on the ND5 Front" now (well actually on its back), maybe it was a switch but it got it's knickers in a twist.

If it was broadcast/multicast I'd expect it to appear on all ports of an unmanaged switch, which it doesn't (/ didn't, seen below).

No need to look it up, it's was an old device, now replaced, but thanks for the offer.

Thanks Chris,

I didn't want to just omit the more controversial bit as I know that in some circumstances some of them can make a big difference, but equally I don't want it dismissed as just another article by someone pushing even more audio pseudo-science.

Some things do seem very variable in effect, and I suspect that environmental influences play a big part in this.  Unfortunately this is quite difficult to test in a rigorous manner.

Regarding Ferrites ....

I went to Maplin today and tried their Ferrite Clip-on HEM 3018 on an Ethernet cable (Cat5e) but it was very loose fitting. Can anyone suggest something tighter fitting rather than making do with blobs of blue tack, or is this as good as it gets.

I intend to buy quite a few Ferrites (as per the excellent guide from Huge) and have seen some very cheap ones available elsewhere but obviously don't want to buy any old rubbish and would rather pay a little more for something that is better suited for the job in hand. Can anyone suggest what to use? 

Forget Maplins,  there are loads of www services out there that sell ferrites,  the bay & the rain forest to name a few.  

I use TDK mix 30 for all my stuff,  I have about 3 cable sizes & all from the same Amaz seller

Maplins HEM 3018 is for 6.5mm cable, whats the OD of your cable.  

If your not happy with bluetak,  insulating tap is just as effective

Cable ties / zip ties are very effective for securing ferrites - just put one round the cable and leave a bit of a tail to stop the ferrite sliding along.

Or if the cable is small enough you can loop it through the choke a few times. This makes the choke more effective and I use this method on DC lines.

Simon

Is it okay to also do this on the Ethernet patch cords too? Probably just one turn to keep in place at each end of the cable. Sorry if this sounds a bit dumb but is there a specific specification/type of Ferrite to use or will any Ferrite (regardless of cost) be fine 

if you can loop the Ethernet patch cord then you could, although because of the twisted pair geometry of the cables the patch leads done like tight bends.

Yes there are different types of ferrites - but not to overcomplicate things most/all commonly available will be fine for our sort of applications.

Simon

One complication (of many) with ferrite mixes is because the same base material gets a different number for different applications.  For what we are doing its best to not get unnecessarily complicated  

MnZn is the most popular for our needs - its found in most all of the ferrite snap-on beads

TDK ZAT2032-0930 (30 is the mix)

Maplins (RadioShack) HEM 3018 (30 is the mix)

Fair-Rite (USA) have the same mix & application numbered as 31

The Fair-Rite data sheet says .........

MnZn ferrite designed specifically for EMI suppression applications from as low as 1 MHz up to 500 MHz. This material does not have the dimensional resonance limitations associated with conventional MnZn ferrite materials. Round cable EMI suppression cores, round cable snap-its, flat cable EMI suppression cores and flat cable snap-its are all available in 31 material.