Would I benefit from adding a switch?

I agree. In particular the isolation transformer should really clamp things down.

Hi Alex,

Really quick guide to ferrets ferrites.

Clip them onto

1  all wires directly connected to your system (including the switch).

2  All Switch Mode Power Supplies SMPS on the same mains circuit (DC and power cables)

3  Your telephone cable next to your cordless phone base station

For SMPS cables and other mains cables put as many turns through the ferrite as possible.  For signal and Ethernet cables just clip it on (not too tight) and don't bend the cable to do it.

Longer description,

see section 2 of this...

https://drive.google.com/file/...S28/view?usp=sharing

Actually if you loop the cable just a couple of times through the ferrite then you will get a significant improvement in the filtering effect. tbh I'm not convinced that the electrons in ethernet cables really mind about going around corners! ;-)

If you look at the longer description I describe that and the radius limitations.

And no they don't mind the corners, but they do mind when the impedance of their environment changes!

...but they can have problems going round tight corners really quickly.

Phil

Huge -  Thank you for sharing the audio networking document link.  What a great resource!  I'm looking forward to giving it a thorough read soon.

Just like your TVR then!

Absolutely ... and electrons make far smaller holes in the hedgerows! *chuckle*

Phil

You should also thank Simon-in-Suffolk and Mike-B , they both made major contributions to getting it 'right'.

Chord quote a minimum radius of 50mm for C-Stream ethernet cable, which is a lot stiffer than the very cheap CAT 5 etc. so you can only loop it through more than once if you don't mind loops of it lying around. Plus you'd need some pretty large ferrites to pass it through more than once.

Sorry to turn the subject back to boring reality, but there you go!

Brilliant, thanks!!!

My system is now almost the 'recommended' one as I have a separate switch and mains conditioning for the NAS, switch and router (not the Naim kit), so I only have the ferrites to go!

Are they all basically the same, or are some makes better than others? Amazon will sell a pack of ten for five or six quid. Obviously I need different diameters for different cables, but is there any reason not to get those?

Thanks again - tremendously helpful.

Alex

Thanks for the link it makes so much more sense now. I guess I'm a visual learner.

The science with ferrite is very complex, however the mix(s) sold on www & the techie stores for home consumer use are most effective in the MHz region that RFI is present.  They start to work around 10MHz & have a reasonably flat impedance from 50MHz up to 100MHz & peak around 300/500MHz.  The make is not so important as they are mostly the same or similar mixes (without getting overly complicated) .  I use TDK (amazon & bay) as I find they are well made in the plastic dept & some have nicely rounded ends that look a bit better than square blocks. 

To add to ChrisSU's point about bend radius,  I would not try to bend a screened cable (C-Stream) they are liable to distort something in the TP or internal separators & the leckytrons have to slow down to go around a bent corner. Given the cable is screened anyhow,  a well firm fitting clamp ferrite is all you need.     

Hi all, I have a question regarding the proper network set up when a switch is present.  My set up is the following

Access Point in bridge mode (Apple Airport Express) wirelessly connected to modem 

                        | 

       Gigabit Switch (TP LINK) 

       ----------------------------------

       |                   |                   |

   NAS              NDX               -------Cat7------ Laptop

     |

  USB disk

I use the USB disk connected to the NAS to take manual backups as a temp solution before a proper RAID set up. Now, what I notice is that when I copy files from the NAS to the USB disk using my laptop to issue the "commands" the process is (a) too slow and (b) depends on whether I connect the laptop wirelessly to the Acess Point or via Ethernet to the switch. Even in the latter case the speed is low (15mbps). Evidently the data travel first to the laptop rather going directly from the NAS to the USB storage device or at least via the switch but not "beyond"  -as I would naively have assumed-. With the switch in place the digital info should not "travel" outside it. Do I need to set up a subnet or what I was assuming to be feasible is not feasible at all?

Yes, ferrite chokes do vary.. Many are effective from 30 MHz to around 100MHz. However a 100Mbps ethernet lead has carrier frequencies around 31 MHz and so that can be a good frequency to focus with ferrites tackling noise from 100 Mbps ethernet patch leads.

To the point of twisting ethernet cables... Well the important thing about Ethernet patch leads is that they use twisted pairs.. A full 5e cable capable of 1gbps will have 4 twisted pairs. The geometry of this twists is important.. it acts like a balanced car wheel and rotates smoothly at speed. Get the twists non uniform, and it's like the car wheel out of balance, and will vibrate more and more with speed, or in the case of the twisted pair emit electro magnetic radiation or RFI. It also makes the twisted pair vulnerable to picking up stray interference.

Now if you bend  your ethernet patch lead too tightly you will distort the twisted pairs and they will go out of 'balance'. Most quality Ethernet cables will have a minimum bend radius quoted such that the characteristics of the cable are not affected. 

Hence the recommendation of not bending the lead too tightly through a ferrite clamp is sensible.

Simon

Hi, this isn't a network problem, rather it's a limitation of the copy command running on your laptop. It doesn't understand that the source and destination drives are on the same device, so has to drag all the data back to the local machine, then write back. Does your NAS have a web interface with a file manager utility? As this runs on the NAS it should be much quicker. 

Donkey's years ago when I worked on Netware there was an ncopy command that understood if both source and destination were on the same server and copied locally if it could. 

Dave

Thanks Dave... Yes, that must be it. Web interface does not provide such copy options, not sure if Robocopy or XXCOPY might do the trick. I will try over the weekend.

Now if you bend  your ethernet patch lead too tightly you will distort the twisted pairs and they will go out of 'balance'. Most quality Ethernet cables will have a minimum bend radius quoted such that the characteristics of the cable are not affected. 

Simon: Can you elaborate on the minimum bend radius. I've got more bends on the 10 metre run from my NAS to my router, than on the M25! 

Hi, yes, it's not the number of bends, it's how sharp the bend is. So imagine you are bending the cable around a large circular pipe , the bend radius would be the radius of the pipe.

Simon

Yes but Novell was a proper NOS unlike that junk that Microsoft churns out where networking is some adjunct tacked on the side of what is essentially a stand alone OS.

Really? I remember Novell well, it was at a time when local and enterprise networks  were hugely less capable than today. It was good, but expensive I seem to remember and didn't integrate that well in my expierience to applications, it really was seen as an adjunct to make up for OS limitations at the time.

I would agree MS Windows back with version 3 was standalone and with WFW 3.11 you could argue networking was a half baked bolt on! but we are back in the days here of Internet being mostly available over very slow X25 links (where 9.6k baud was a good speed) for large corporations  and networks were largely about internal enterprise connectivity. But in my expierience from NT onwards, Windows has embraced networking, and current versions are network centric IMO. 

Many of our cloud and  web services we use today on the Internet are powered by MS Windows Server versions behind the scenes. If it was  junk, I suspect much of our e-commerce would grind to a halt.

I have no axe to grind either way, but I do design and build systems 'behind the scenes'

Simon 

I used to use OS/9 and OS/9000 back in the late 80's to implement real-time process control and monitoring systems (worked on a wind tunnel for Redland tiles, test cells for Electrolux Finland for testing fridges and freezers and environmental monitoring for Dartford tunnel amongst others) and I think what the distinction you guys are looking for is that with OS/9 and OS/9000 (and I think Novell did this too) you could jump around processors that were attached to your network and run processes wherever they were most effective, so lets say you had a compile to do and your colleague was out for the afternoon then you could change processors over to his machine and run your compile on there - that functionality was part of the baseline OS whereas with Windows and Apples OSX you are very much restricted to your own device and the networking functionality is primarily for data transfer only.

No?

Phil

I think the rise of MS network solutions has been very aggressive pricing and the fact that, typically (but not all) SI customers couldn't get their head around Novell. As a company we used Novell for over a decade and found it extremely fast and very, VERY stable.... We had servers running that typically ran for years without having to touch them or do a reboot - no security patches every week! It was only a cost issue that forced us to change three or four years ago and then we went for a Linux based system. The problem was the old Novell we were using wouldn't work with larger capacity SATA drives so it was upgrade or change :-(

I remember we put a Novell setup into a school running diskless Win95 computers and many years later the school were bribed by the local educational dept to go the MS route. As part of this changeover they had to find the Novell server. Nobody knew where it was! In the end it was found in a cupboard that had been walled in. It had sat there running with zero maintenance for years and nobody had to touch it!

Those were the days.... ;-)

Although it's a digression from the subject, from its inception onwards, Windows NT was built as a secure network platform.  Indeed the original security system (still optionally trusted today) was NTLM - NT LAN Manager.  Networking and security control were integrated together into the very heart of the OS.

In terms of moving code between processors, such code is referred to as transportable code and is a big problem for system security.  Normally such code is now only permitted to run in a virtual machine that imposes severe limitations on the actions it can perform.  This approach is supported in NT derived environments.  Executing transportable code outside this restrictive environment is normally not allowed.

Older LAN OSs, if now connected to the internet (as a WAN) are extremely vulnerable to attack.  If stand alone, they can function safely indefinitely.  However if you want internet access, then you really should use a more modern OS that's been kept up to date.

DrPo -- what brand is your nas?  Many nas's have their own backup utility, which you can use to backup from the nas to an attached usb drive.  Such backup utilities usually provide for periodic, unattended, differential backups -- another benefit.  That is, if backing up is what you're trying to do, vs. just copy files.  But the nas should have a file manager of its own so you can copy files directly.

Otherwise, as Dave wrote, you've got the limitations you noticed.  Can always just let it run overnight, etc.