1 (edited by berlin_ 2019-03-24 02:38:42)

Topic: Question about new AVB m32 pro

If I connect let's say a mic preamp via MADI will the inputs be discoverable via AVB network?

Also setup is PC -> Router -> M32?

Thanks

2

Re: Question about new AVB m32 pro

If you route them via TotalMix to the Network output channels you will get the audio. But there is no control of the mic amp via network.

Regards
Matthias Carstens
RME

3 (edited by berlin_ 2019-03-25 04:35:13)

Re: Question about new AVB m32 pro

Hello, thanks for the answer.

Is there a sample setup for the whole AVB network thing for studios? Recommended/working network cards/router/software for PC?

I have done some research and compared to Dante it is all pretty vague still.
Are there any plans on releasing more AVB network I/Os, premaps, etc?


Wanted to share a little list of potential cards and more... for PC users:

AVB for PC:

https://1drv.ms/w/s!AsdhRYxqnBY1hYB88HYm_VkbC--shQ


To run the device do we need the AVDECC Controller software or is there something included?

MACs should be able to directly connect to AVB networks?

What about laptop PCs? Any recommended laptops?

Would be awesome to collect a list or some sort of database. Would make my decision much easier.

Also the network setup for AVB. Any articles or guides on that? How to combine it with internet/wlan/lan etc

Thanks

4 (edited by ramses 2019-03-25 09:02:36)

Re: Question about new AVB m32 pro

Here a collection of information regarding AVB switches

One Use Case with Cisco Stackable Switches and Performance Measuring by Miercom
Contains interesting Information about Performance Measuring and Values (Latency,...)
https://www.google.de/url?sa=t&rct= … BH-GiyQ_vc

https://www.cisco.com/c/en/us/products/ … s/avb.html
This overview contains very interesting information about AVB.
Among other things a very good whitepaper and FAW about this topic.
Towards the bottom of the webpage you will find this useful information:
Resources
    At-a-Glance
    Overview
    White Paper
FAQs
    Audio Video Bridging FAQ

Cisco: Interestig collection of facts what is required to run AVB on Cisco Switches
- device models
- required IOS and license levels
- important limitations, which switch ports support AVB, etc
- how to enable AVB on the switches
- show commands for AVB
https://support.biamp.com/Tesira/AVB/En … t_Switches

Audio Video Bridging Configuration Guide, Cisco IOS XE Everest 16.5.1a (Catalyst 3850 Switches)
https://www.cisco.com/c/en/us/td/docs/s … er_00.html

More devices / vendors for AVB switches:
https://support.biamp.com/Tesira/AVB/Li … t_switches

IEEE Standards to which products should be compliant for AVB

IEEE 802.1AS: Generalized Precision Time Protocol (gPTP), which provides timing and synchronization
for time-sensitive applications on Layer 2 devices.

IEEE 802.1Qat: Stream Reservation Protocol (SRP)/Multiple Stream Reservation Protocol (MSRP),
which is an end-to-end traffic admission control system that helps ensure the availability of
resources, such as bandwidth and latency, that are required to transport AV streams.

IEEE 802.1Qav: Forwarding and Queuing for Time-Sensitive Streams (FQTSS), which is AV traffic
scheduling capability for mainstream Ethernet and other network switches.

IEEE 802.1BA: An umbrella standard for the other three IEEE 802.1 standards that defines profiles
for features, options, configurations, defaults, protocols, and procedures for AVB devices.

BR
Ramses
X10SRi-F, Win7 Prof, Cubase 9.5, UFX+, Octamic XTC, ADI-2 Pro FS BE/DAC, RayDAT, ARC USB

Re: Question about new AVB m32 pro

Thanks

Really love RME, but the whole AVB thing seems to be kinda uncharted territory especially for PC users.

6 (edited by ramses 2019-03-26 08:07:02)

Re: Question about new AVB m32 pro

berlin_ wrote:

Thanks

Really love RME, but the whole AVB thing seems to be kinda uncharted territory especially for PC users.

It's like with many things, you have to inform yourself. But one should not overproblematize things either.

Basically it is quite simple, for a 1 switch installation I see no major problems, you need nothing more than that:
- AVB Recording Interface
- One or more AVB compliant Network Switches
- AVB equipment (Preamps, ADDA converter)

The network card on the computer is not of interest at first, because the AVB audio streams run via the LAN port of the RME AVB Recording Interface, which (as of today, as long as there are no PCIe versions) is connected to your computer via USB.

The only thing I'm wondering is whether there are any quality differences between different AVM switches i.e. in terms of latencym, but potentially not as in a Gigabit network the RTT is much below 1ms. Switches work on Layer 2 and thus are very fast forwarding packets.

So there are probably no major problems with a 1-switch installation and a few devices.

The challenges will potentially come as soon as

1. multiple switches are required
2. path redundancy is required with quick recovery times in the case of a link failure (-> spanning tree)
3. all possible network traffic uses the same LAN infrastructure (UC - unified communication: voice, video, office traffic). When delay and jitter sensible traffic meets office and bulk traffic (large internet downloads, backup over same network infrastructure)
4. you want to implement also VoIP phones with PCs connected behind the VoIP phones and if you additionally require PoE (Power Over Ethernet) or PoE+ to power the VoIP phones via the LAN cable to save cabling efforts.

In this case Audio and typical Network topics mix.

As I said, for small AVB deployments (1-switch deployments) I see no major issues.

When having 2 switches you need to think already about 2 links between the switches for redundancy reasons. Then your switch should support Rapid Spanning Tree Protocol (RSTP, IEEE 802.1w) which allows for recovery times below 1 second compared to ~45s when using the old STP protocol (IEE 802.1d).

BTW; I found a nice article on Heise (in German though) which is quite comprehend on STP, shall it be of interest.
https://www.heise.de/ct/artikel/Erweite … 28147.html

BR
Ramses
X10SRi-F, Win7 Prof, Cubase 9.5, UFX+, Octamic XTC, ADI-2 Pro FS BE/DAC, RayDAT, ARC USB

7 (edited by Max 2019-06-21 03:58:59)

Re: Question about new AVB m32 pro

I agree that it must appear quite vague and blurry to newcomers.

berlin_ wrote:

Is there a sample setup for the whole AVB network thing for studios? Recommended/working network cards/router/software for PC?

As Ramses says, it shouldn't require a specific sample setup. While it is not necessary to understand all the AVB specifics, you should understand one thing about AVB, which is the concept of streams. Streams are like virtual cables across your AVB network, and are shielded from other traffic and deterministic (they have a fixed latency).

This is different from legacy ethernet or 'Layer 3' network technologies. In terms of interoperability, you usually only need to check the supported stream size on both ends, but in future you don't even have to check that, because the subset of AVB marketed as 'MILAN' makes a certain stream size mandatory for manufacturers. Two MILAN products can always connect, two AVB products only if they support the same stream size. See also this video: https://www.youtube.com/watch?v=FodSNTc2zrM

While RME is not a member of the MILAN group at this time, it is obvious that MILAN is the only possibility to achieve guaranteed plug'n'play interoperability, which is what customers need. So the current firmwares of Digiface AVB and M-32 Pro series already play nicely with MILAN products.

berlin_ wrote:

I have done some research and compared to Dante it is all pretty vague still.
Are there any plans on releasing more AVB network I/Os, premaps, etc?

That is maybe due to Dante being a network solution that has always been marketing-driven (give customers a solution that solves their problems now), while AVB is by itself only an open set of standards and the people implementing it are technology-driven (give customers a great solution once the standards are tackled and the implementations mature). By allowing common switches, Dante could solve many issues much faster. And they did this very well!

AVB builds on an enhancement of Ethernet, which requires the IT industry (which is in comparison to the audio industry a HUGE industry) to implement these standards first (small switch manufacturers follow the implementations of huge switch manufacturers such as Cisco, and that takes time). It looked like it would never happen a couple of years ago, that may be one of the reasons Audinate/Dante 'pulled the plug' on their AVB implementation (they wanted to use the advantages of deterministic ethernet in the beginning, see: https://www.lectrosonics.com/Support/ph … v1%202.pdf).

While that was bad 'marketing' for AVB, it actually did not mean that the underlying technology wasn't superior or would be obsolete. In fact, also the much newer AES-67 standard mentions AVB as an enhanced ethernet technology that can be used to improve performance in other types of networks. I personally assume that deterministic ethernet will become much more common in consumer switches, many devices already have the required chips inside and simply didn't activate them (I'm looking at you, Linksys WRT3200ACM!).

Of course more AVB products are planned. The motivation behind it is simple:
a) it's an open standard that manufacturers can fully understand and develop with - they can use existing implementations or develop their own (as RME did)
b) it solves the remote control issues that MADI has (AVDECC can be used to control any parameter, for example of an M-32 DA pro, including output gain, clock, preset switching, even metering options, and yes, you can even turn on dark mode if the AVDECC controller has implemented the corresponding control). So there is no need to implement our own remote control, which is the case with most other network audio technologies.
c) it solves the cable issues that MADI has (optical and coaxial cables are not the best option for live recordings...). Also, more audio channels at higher sample rates per cable, see http://abc.statusbar.com
d) routing!
e) no dedicated network is required, even in complex setups. Users who use new features like cloud collaboration on their DAW should not need to run a separate network just for internet.

berlin_ wrote:

To run the device do we need the AVDECC Controller software or is there something included?

The Digiface AVB has an AVDECC Controller as part of the driver to connect streams and set the clock, but you can also use the other controllers available, such as HIVE (search Google for HIVE AVB Controller).

berlin_ wrote:

MACs should be able to directly connect to AVB networks?

Yes, they can, if they use the Thunderbolt 2-1GigE adapter with Broadcom chip (USB adapters do not work). The current developer Beta of Mac OS 10.15 has even implemented the MILAN stream format (AAF), which I haven't tested yet.
I have not done recordings with the built-in AVB capabilities of my Mac though, and there have been reports that it doesn't work well in combination with certain AVB implementations or certain Mac models. A Digiface AVB with its USB 3 Core Audio drivers is a much better solution for anyone relying on their AVB connection for professional recordings - the built-in capabilities can be tested and used for non-critical applications, such as backup recording etc.

berlin_ wrote:

What about laptop PCs? Any recommended laptops?

It should have USB 3.0. Apart from that, just follow optimization guides for any USB audio interface (DPC latency etc.).

berlin_ wrote:

Would be awesome to collect a list or some sort of database. Would make my decision much easier.

I noticed that you are researching adapters that are gPTP aware and support the other AVB standards, like the Intel I210. Keep in mind that this is just one part of what you need. You also need an ASIO driver, for example, which plays nicely with the adapter. An I210 by itself does not bring audio to the DAW.

berlin_ wrote:

Also the network setup for AVB. Any articles or guides on that? How to combine it with internet/wlan/lan etc

With the cheaper switches, you don't need to set anything, it's plug and play. Once you connect the devices, they appear in the AVDECC Controller and all you need to do is set a media clock master, then connect the streams.

AVB streams require a LAN connection with AVB switches. The AVDECC discovery and remote control protocol itself is ok with any LAN connection, also without AVB switches. A web based remote control GUI as the M-32 Pro provides can be accessed via any network, including Wifi. You can connect AVB switches to non-AVB switches and routers, as long as the audio streams do not have to pass these non-AVB routers to reach their destination.


ramses wrote:

The only thing I'm wondering is whether there are any quality differences between different AVM switches i.e. in terms of latencym, but potentially not as in a Gigabit network the RTT is much below 1ms. Switches work on Layer 2 and thus are very fast forwarding packets.

There are performance differences, but for a normal studio setup, let's say less than 150 audio channels and less than three or four switches, probably less than 30 streams, they do not reveal themselves at all. The reason for that is that any latency caused by a switch does not have an effect on the latency of the audio stream, which is defined as an offset by the 'talker'.

This offset (presentation time offset) is specified in the standard for seven switches at 100MBit (sic!) as 2ms, but in reality much shorter offsets can be set on 1GigE with fewer switches. That is why you can set the presentation time ('network latency') to lower values, for example 0.3 ms, if the talker supports it (RME devices do). The great thing about AVB is: if your network is too slow (ie. you have ten Switches in a row and try to set 0.3 ms), the stream simply cannot start (the receiver says: oups, that point of time has already passed, sorry!). If it starts, however, each switch along the way ensures that it will also stream when the network traffic increases, or the switches are experiencing extremely high traffic, and so on. No matter if it is a cheap AVB switch or an expensive one, as long as it is an AVB switch.

Example: a mic preamp establishes a connection to an M-32 DA Pro with a presentation time offset of 0.6 ms added to the gPTP time stamp of the samples. Since in an AVB network, both devices have the exact same time, they are fully synchronized to a couple of nanoseconds. The M-32 DA receives the samples with any latency that incurs on the network and then buffers the samples until presentation time specified by the talker. It is therefore possible to play the same impulse at the exact same time across different branches of a network, one stream only passing one switch, the other passing seven switches, without the switches causing delay or other issues. In fact, since AVB switches all reserve traffic for AVB when the stream is established, you can download Windows and Mac OS updates and upload to Youtube at the same time over the same network - the impulse will still be played out exactly at the specified time. If that cannot be achieved for some reason, it does not play at all. Haven't seen that happening, very unlikely because of the way traffic is prioritized and reserved in the switches.

You can benchmark a network with a Digiface AVB. It shows you how long it has to buffer ('input delay') the first incoming stream, and therefore it is very easy to compare two AVB switches or your network performance and guide you to the lowest offset setting.

Hope this cleared things up a little.

Max
RME

8 (edited by ramses 2019-06-21 06:02:07)

Re: Question about new AVB m32 pro

Many thanks for this very informative posting Max.

Do you think that AVB has lower latencies or some advantages over Dante as the quality is already being established on Layer 2 ?

What happens for AVB if sender and receiver live on different subnets and the traffic needs to be routed ?
Does this require QoS configuration on the Router to priotize the traffic ?
Or do you need a L3 AVB capable Switch for that that knows some more "tricks" ?

BR
Ramses
X10SRi-F, Win7 Prof, Cubase 9.5, UFX+, Octamic XTC, ADI-2 Pro FS BE/DAC, RayDAT, ARC USB

9 (edited by Max 2019-06-21 08:36:11)

Re: Question about new AVB m32 pro

ramses wrote:

Do you think that AVB has lower latencies or some advantages over Dante as the quality is already being established on Layer 2 ?

I do not think that the overhead caused by L3 is causing a significant delay by itself.

ramses wrote:

What happens for AVB if sender and receiver live on different subnets and the traffic needs to be routed ?

You create a handover point on one network to a L3 network protocol, which then sends via router to the next handover point in the second AVB cloud. While it would be possible to do some sort of AVB over L3 (there were considerations, I think it hasn't happened), I believe in such complex scenarios a bridge to AES-67 would be much more popular. And don't forget that AVB can peacefully coexist with L3 technologies on the same network.

ramses wrote:

Does this require QoS configuration on the Router to priotize the traffic ?

Yes. As long as your in your AVB Cloud, you don't need to configure anything in the switches. Once you want to route across subnets over L3, you can put your IT hat on and get into the complexities of network administration.

ramses wrote:

Or do you need a L3 AVB capable Switch for that that knows some more "tricks" ?

A switch itself cannot encapsulate L2 AVB streams into L3 IP based streams. The abovementioned handover points could be designed like a dongle that you connect to your AVB-capable switch. It receives streams like any other AVB endpoint, translates them to Dante, AES-67, Soundgrid or whatever, and then sends the data to a L3 endpoint - and the other way round. Those kinds of devices will be more common in future, since network audio is not a battle where one protocol must win.
What the switch must support once the audio goes to L3 is a different story. Luminex switches are great for all sorts of network audio technologies, so if you aim to have complex networks, that's probably a future-proof investment (end of advertisement).

10 (edited by ramses 2019-06-21 08:51:21)

Re: Question about new AVB m32 pro

Is there already any experience out which manageable L2 / L3 switches give the best bang for the buck ?

And if you have to use a core/distribution and several access switches, which switches offer technologies to avoid blocked backup ports by spanning tree.

Cisco is good but also pricy, therefore in the enterprise area many companies switch to HP / Aruba switches
in the distribution / access area.

As a SOHO (Small Office / HO Customer) it would be good to know what manageable switches give a certain good value / feature set.

BR
Ramses
X10SRi-F, Win7 Prof, Cubase 9.5, UFX+, Octamic XTC, ADI-2 Pro FS BE/DAC, RayDAT, ARC USB

11

Re: Question about new AVB m32 pro

Yes, as I said, Luminex is great. Since we seem to be getting off topic here, let me just say that AVB standards are meant to automate and hide the complexities of IT network administration behind the scenes. It should be plug and play, and no user in the RME forum should ask how to set QoS or backup ports, spanning tree protocol and so on, especially not in SOHO setups. This forum is for recording, not for IT after all. A SOHO customer should never touch switch configuration, and never have to worry about black-lists and white-lists of recommended switches. That is maybe the biggest benefit of AVB - predictable, stable performance that scales without configuration or choice of switch manufacturer.

12 (edited by ramses 2019-06-21 09:49:05)

Re: Question about new AVB m32 pro

1st of all many many thanks that you share your knowledge and views on this topic with us.

I do not think that this is really an off-topic thema.

We live in a complex IT world and its not always so simple as you say, especially as you mention yourself, that AVB or Dante deployments are not isolated islands for audio like i.e. a MADI based installation dedicated for audio/recording.

Everything today is about converged communications: Data, Voice, Video everything over one network infrastructure
and now on top reliable real-time transport of audio streams.

Then specialities on top like
- LACP for port bundling to connect i.e. NAS
- 5G / 10G upcoming, also for PCs

As features and prices differ very much I could think of, that customers would be very happy to see, what other ppl are using with good success to have a good starting point.

I agree, that for people only using a little installation with zero additional demands, no voice, no NAS, no multiple PCs etc .. things of course would be much easier. But as soon as you have an office with several ppl and recording rooms, then it becomes quickly interesting what producs perform, offer many features but are still payable.

It was already great to hear about Luminex switches in this thread, I didn't hear of this company yet, so will definitvely have a look at them, many thanks ;-)

BR
Ramses
X10SRi-F, Win7 Prof, Cubase 9.5, UFX+, Octamic XTC, ADI-2 Pro FS BE/DAC, RayDAT, ARC USB

Re: Question about new AVB m32 pro

Just a quick note regarding redundancy:

STP and related mechanisms have been (and are still) discussed heavily within the AVB/TSN working group. However, Milan specifies redundancy just like Dante or Ravenna do: Having two separate networks where failover happens in the end points.

So while it is totally possible to have spanning trees (but requires quite some knowledge), the more practical and much easier way is to setup to independent networks with redundancy handled by end points.

14

Re: Question about new AVB m32 pro

berlin_ wrote:

If I connect let's say a mic preamp via MADI will the inputs be discoverable via AVB network?

Using the M-32 Pro Remote Control (web interface) or the menu on the device itself, you first route the corresponding MADI inputs to one of the four M-32 Pro output streams (which can each contain 1-8, 12, or 16 channels up to 96k, or 1-8 or 12 at 192k). Then, these Mic Pre signals can be discovered by any AVB listener on the network as channels within the M-32 output streams.

The streams are then connected between AVB devices, for example to your Digiface AVB, where they appear in TotalMix, and they will remain connected and bandwidth will be reserved no matter if the Mic Preamp sends its signals or not. As mentioned earlier - it's like virtual cables. Also as MC says, these virtual cables do not transport the embedded MIDI over MADI signals (currently) in case your mic pre uses that for remote control.

Internally, the M-32 Pro has a routing matrix where incoming and outgoing AVB (each direction up to 64 audio channels) and MADI signals (up to 128 audio channels via two MADI ports) are treated the same way as the analog ones, so you have a very powerful 192*224 matrix under the hood, including MADI splitting, merging, MADI to AVB, AVB to MADI, and so on.