# Network Stress Test



## mjwagner (Oct 8, 2005)

Was hoping someone with DECA could try this as I am interested in how DECA is going to hold up under this load. I do not have DECA and am using my wired Ethernet network. Here is a description of the test. Can someone with DECA and the required rcvrs try this and post your results?

A test of the robustness and capability of Ethernet. Among my other D receivers I have 2 HD-DVR's, lets call them 1 and 2, they are on different floors in my home. On 1 I started watching a HD show that was recorded on 2, and on 2 I started watching a HD show that was recorded on 1. Then on both 1 and 2 I started to DL an HD show from VOD (different shows on both). That means that on each of the Ethernet wires attached to each of the DVR's I had two streams of HD video flowing, one out and one in, and one stream of data being downloaded. All that traffic going thru my network. It worked flawlessly including all trick play features. No pixilation, no stuttering, no delays, nothing. Rock solid. 

I think this is a pretty good 'real world' stress test. I'm suspecting (hoping) that DECA will be able to handle it just as well as my wired Ethernet LAN.


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## veryoldschool (Dec 10, 2006)

Not exactly the same tests, but I've had three ins & three outs all running at the same time with zero issues.


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## dennisj00 (Sep 27, 2007)

Again not exactly the same, but I've had my 5 HR2xes in a round robin, as a client for another box. In addition recording 2 programs each and downloading a VOD each.

Trickplay is very crisp and pictures perfect.

My broadband deca is across a wireless N (5gb) which I also used very successfully for 2 HRs pre DECA.


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## mjwagner (Oct 8, 2005)

veryoldschool said:


> Not exactly the same tests, but I've had three ins & three outs all running at the same time with zero issues.


Not sure I understand what you mean. Trying to come up with the highest network load I could devise I could only come up with 2 in (HD video coming from another DVR on the network plus a VOD download) and 1 out (HD video going to another rcvr on the network). Are you saying there is a way to get 3 in's and 3 out's on a single unit over the network at the same time? Let me know how. I would love to run that as an even greater network stress test on my Ethernet LAN. Please limit it to 'network' traffic only. In other words for me anything going on on the coax side doesn't count. For a DECA installation only DECA traffic counts.


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## mjwagner (Oct 8, 2005)

dennisj00 said:


> Again not exactly the same, but I've had my 5 HR2xes in a round robin, as a client for another box. In addition recording 2 programs each and downloading a VOD each.
> 
> Trickplay is very crisp and pictures perfect.
> 
> My broadband deca is across a wireless N (5gb) which I also used very successfully for 2 HRs pre DECA.


I'm really trying to isolate and produce a 'maximum network traffic' test. So anything going on on the coax or non-DECA side of things really doesn't matter.

I am definitely expecting DECA to handle it just as well as Ethernet but am curious to have someone try it..


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## harsh (Jun 15, 2003)

mjwagner said:


> Not sure I understand what you mean. Trying to come up with the highest network load I could devise I could only come up with 2 in (HD video coming from another DVR on the network plus a VOD download) and 1 out (HD video going to another rcvr on the network). Are you saying there is a way to get 3 in's and 3 out's on a single unit over the network at the same time?


DECA network loading must take into consideration all the equipment on the cloud. The issue isn't the Ethernet port on the receiver but how much traffic the cloud can hold.

Because DECA is a token-based scheme with only one communications path, all devices must wait their turns. As the lone path gets loaded up, that's where things could break down.

In your switched Ethernet scenario, having two sessions going on at once is as far as you need to go but with DECA, the whole network is exposed to all traffic.


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## The Merg (Jun 24, 2007)

dennisj00 said:


> Again not exactly the same, but I've had my 5 HR2xes in a round robin, as a client for another box. In addition recording 2 programs each and downloading a VOD each.
> 
> Trickplay is very crisp and pictures perfect.
> 
> My broadband deca is across a wireless N (5gb) which I also used very successfully for 2 HRs pre DECA.





mjwagner said:


> I'm really trying to isolate and produce a 'maximum network traffic' test. So anything going on on the coax or non-DECA side of things really doesn't matter.
> 
> I am definitely expecting DECA to handle it just as well as Ethernet but am curious to have someone try it..


Sounds like Dennis's test matches yours and even goes a step further. He had 5 MRV streams running at once, plus VOD on all 5, plus he taxed the CPUs even more by recording 2 programs on each DVR.

- Merg


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## mjwagner (Oct 8, 2005)

Perhaps I'm not clear on the description but it did not sound like Dennis's test did match mine. I'm just trying to isolate the network so the recording part of it does not come into play as I am not, at least in this test, interested in testing the rcvr cpu capacity. You need to be both serving up and receiving an HD video stream and DL'ing VOD *simultaneously on each rcvr*. From the description it sounded like he was just serving up 5 video streams from 5 dvr's which is not the same. But again I admit that I am not entirely clear about it based on the description.


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## dennisj00 (Sep 27, 2007)

One stream in and one out plus a VOD is currently the maximum network traffic an HR2x can produce. Should be no problem for a 100mb port.

If you continue to use ethernet, just arrange the H/HRs on a common switch, if possible. This 'isolates' the MRV traffic.

I might add, I had excellent performance with my pre-DECA wired / wireless configuration with MRV. The only reason I went with DECA was I added a 5th HR and went to a SWiM 16 installation at the same time.


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## dennisj00 (Sep 27, 2007)

mjwagner said:


> Perhaps I'm not clear on the description but it did not sound like Dennis's test did match mine. I'm just trying to isolate the network so the recording part of it does not come into play as I am not, at least in this test, interested in testing the rcvr cpu capacity. You need to be both serving up and receiving an HD video stream and DL'ing VOD *simultaneously on each rcvr*. From the description it sounded like he was just serving up 5 video streams from 5 dvr's which is not the same. But again I admit that I am not entirely clear about it based on the description.


Who was the client in my 'round robin'? Each dvr was a client to another so each was serving up a stream (out) and playing a stream (in).

Even though you have 4 boxes, 2 HRs, 2 Hs, you can only have 2 streams going at the same time. Either your H2x receivers are clients or your HRs can be a client to each other.


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## veryoldschool (Dec 10, 2006)

mjwagner said:


> Not sure I understand what you mean. Trying to come up with the highest network load I could devise I could only come up with 2 in (HD video coming from another DVR on the network plus a VOD download) and 1 out (HD video going to another rcvr on the network). Are you saying there is a way to get 3 in's and 3 out's on a single unit over the network at the same time? Let me know how. I would love to run that as an even greater network stress test on my Ethernet LAN. Please limit it to 'network' traffic only. In other words for me anything going on on the coax side doesn't count. For a DECA installation only DECA traffic counts.


With three DVRs, I was able to have one more stream than you did, all within DECA.
"Actually" I may have had four streams going at one time, since I did have four DVRs active, though I've reduced this back to three now.
With the H/HR24s you can test the PHY rates of the DECA which can be around 255, so comparing to a 100 Mb/s ethernet, the DECA seems to be slightly better.


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## mjwagner (Oct 8, 2005)

dennisj00 said:


> Who was the client in my 'round robin'? Each dvr was a client to another so each was serving up a stream (out) and playing a stream (in).
> 
> Even though you have 4 boxes, 2 HRs, 2 Hs, you can only have 2 streams going at the same time. Either your H2x receivers are clients or your HRs can be a client to each other.


As I said it wasn't clear to me based on your description. I didn't understand what you meant by 'round robin'. Based on your clarification it sounds like you did duplicate the same conditions. Appreciate the clarification.

Yes, unfortunately I only have 2 dvr's so can't go beyond what I did. However, since my backbone LAN is Gigabit and my D equipment is all on the same 8 port switch it really would not make a difference.

Based on these results it appears that DECA and a wired Ethernet LAN are equivalent from a performance perspective based on current MRV capability. It is what I had expected based on my experience.

Appreciate the confirmation on the DECA side.


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## dennisj00 (Sep 27, 2007)

Other than being 'unsupported' by D*, you should have no problems. You just need to know enough about your network to avoid problems.

My example is overkill since I only have 2 TVs but is probably around 50% of what the DECA cloud can do. I'm not worried about its performance.


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## mjwagner (Oct 8, 2005)

Since I designed and installed my network along with the rest of my telecom/sat installation in my house when I designed the house and had it built back in 2008 yeah, I guess I know enough about my network...

Here is a pick of the wiring closet:


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## harsh (Jun 15, 2003)

veryoldschool said:


> With the H/HR24s you can test the PHY rates of the DECA which can be around 255, so comparing to a 100 Mb/s ethernet, the DECA seems to be slightly better.


A 100Mbps five port switch has 500Mbps to 1Gbps of bandwidth and a 5 port gigabit switch has around 5-10 Gbps of bandwidth. Switches with more ports usually have even greater bandwidth.

Comparing on specifications (especially PHY rates) doesn't make a compelling case for DECA against 100Mbps switched Ethernet. The MoCA bitrate is just under 50% the PHY rate so using your findings, that equates to about 125Mbps of total bandwidth.

I think I saw a white paper somewhere that indicated that the practical top end for MoCA 1.1 was about 175Mbps.

http://www.michaelsinsight.com/2009/11/moca-plans-new-higher-bandwidth-standard.html


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## Doug Brott (Jul 12, 2006)

harsh, in a perfect world perhaps Ethernet ports would be fine, but you've gotta know that some of these cheap Gigabit routers are only burst speeds and sustained speeds aren't that fast.

Clearly you're not a DECA believer .. and that's fine .. but the overwhelming empirical evidence certainly suggest it to be a medium that works quite well. Maybe you can give it a try yourself one day and become a believer.


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## Doug Brott (Jul 12, 2006)

mjwagner said:


> ...
> 
> I think this is a pretty good 'real world' stress test. I'm suspecting (hoping) that DECA will be able to handle it just as well as my wired Ethernet LAN.


Your stress test isn't much of a stress .. The only times I've seen people starting to complain about DECA performance is when the Device count exceeds 5 and there was massive cross-talk on what shows were being watched.

The simple answer to your question is yes, DECA will be able to handle 1 in, 1 out and 1 VOD per device .. It this (really basic) configuration didn't work, you'd definitely hear about it.


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## mjwagner (Oct 8, 2005)

Doug Brott said:


> Your stress test isn't much of a stress .. The only times I've seen people starting to complain about DECA performance is when the Device count exceeds 5 and there was massive cross-talk on what shows were being watched.
> 
> The simple answer to your question is yes, DECA will be able to handle 1 in, 1 out and 1 VOD per device .. It this (really basic) configuration didn't work, you'd definitely hear about it.


Agree, but with the equipment that I have it was the best (most stressful) that I could do.

I have been a D subscriber since 1996 and really do want to see D and DECA be a success. However, and please I don't want to resurect this discussion as it has been had ad nauseam in various threads for some time now, the thing that gets me concerned is when supporters of DECA claim that somehow Ethernet LAN technology is not capable of handing the traffic required to support MRV. I just don't understand why it's not enough to simply state that DECA is easier for the D installer community to work with and install and uses technology (coax) that they are already trained on, and that it is also a 'controlled' environment that allows D to easily and cost effectively maintain/troubleshoot, and fix, using the wiring that most people already have. To me that is perfectly understandable and makes complete sense.


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## harsh (Jun 15, 2003)

Doug Brott said:


> Clearly you're not a DECA believer .. and that's fine .. but the overwhelming empirical evidence certainly suggest it to be a medium that works quite well.


I'm not claiming that DECA doesn't work well for many as many have testified that it works fine for them.

I'm simply shining a little light on the truth where there is a decided misrepresentation about the what the data means on a comparative level.


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## armchair (Jul 27, 2009)

mjwagner said:


> Agree, but with the equipment that I have it was the best (most stressful) that I could do.
> 
> I have been a D subscriber since 1996 and really do want to see D and DECA be a success. However, and please I don't want to resurect this discussion as it has been had ad nauseam in various threads for some time now, *the thing that gets me concerned is when supporters of DECA claim that somehow Ethernet LAN technology is not capable of handing the traffic required to support MRV. I just don't understand why it's not enough to simply state that DECA is easier for the D installer community to work with and install and uses technology (coax) that they are already trained on, and that it is also a 'controlled' environment that allows D to easily and cost effectively maintain/troubleshoot, and fix, using the wiring that most people already have. To me that is perfectly understandable and makes complete sense.*


DECA is comparatively the same for me but usually there is no more than two HD-DVRs streaming at a time. I've done those tests with no issue on DECA and wired ETHERNET. I had an *occasional* distorted audio and video for a couple of seconds with wired ETHERNET and were initially seen over DECA as well; however, I cannot recall if the occasionals were fewer or the same. My initial impression of the switch to DECA was that TP was faster but still prone to stumble the audio and video recovering from TP.

With that in mind, how is your TP (trickplay) performance?

This improved with DECA and DECA also seems to have improved the TP audio sync and audio transitions smoother. How's your audio transitioning coming out of TP?

Does your UPL stay updated for months w/o fail? Back in those ETHERNET days, occasionally I'd have a DVR that would need a restart because it stopped updating the UPL. While I'm on that subject, it seemed the server DVR required more restarts for failed MRV streams that caused the DVR to not be seen by the other.

I wouldn't know if ETHERNET has benefited from these improvements but I've seen these improve with DECA. In my experience, DECA may be faster and more reliable for TP but maybe it's the evolution of the f/w changes since I switched? Do you think both have benefited equally over time?

In my comparisons, I had two HR22-100s with ETHERNET and now two HR24-200s with DECA. It seems that the HR24s were intended/designed for DECA, not ETHERNET. They do work with ETHERNET but have been noted to be stubborn when connected in SWM systems using ETHERNET (it's another subject but a Band-Stop-Filter is recommended for those users). I'm just saying, there may be reasons that DECA is preferred by users that tried both setups. (the evolution of f/w and transitioning to HR24s)


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## mjwagner (Oct 8, 2005)

armchair said:


> ...
> 
> With that in mind, how is your TP (trickplay) performance?
> 
> ...


I can't comment on DECA at all as I have no experience with it. My Ethernet has been rock solid since MRV went national. I had issues during the beta but they were all attributable to the beta MRV code and not my network. Keep in mind though that I am not the typical consumer for which DECA was designed. I have a hardwired network with cat5e and all gige switches with all of my D rcvrs isolated on one of my 8-port switches. My LAN backbone has better specs than the current MoCA implementation that DECA is based on.

The important thing to keep in mind is the problem that DECA was designed to solve. That is not people like me who have well architected GigE based hardwired networks. It is the average consumer who really does not know the difference between a router and a switch and typically does not have a hardwired Ethernet network already installed.


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## Doug Brott (Jul 12, 2006)

harsh said:


> I'm not claiming that DECA doesn't work well for many as many have testified that it works fine for them.
> 
> I'm simply shining a little light on the truth where there is a decided misrepresentation about the what the data means on a comparative level.


which simply means you're not a believer ..


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## Doug Brott (Jul 12, 2006)

mjwagner said:


> I can't comment on DECA at all as I have no experience with it. My Ethernet has been rock solid since MRV went national. I had issues during the beta but they were all attributable to the beta MRV code and not my network. Keep in mind though that I am not the typical consumer for which DECA was designed. I have a hardwired network with cat5e and all gige switches with all of my D rcvrs isolated on one of my 8-port switches. My LAN backbone has better specs than the current MoCA implementation that DECA is based on.
> 
> The important thing to keep in mind is the problem that DECA was designed to solve. That is not people like me who have well architected GigE based hardwired networks. It is the average consumer who really does not know the difference between a router and a switch and typically does not have a hardwired Ethernet network already installed.


I will say this .. If you're happy with your Ethernet setup. You shouldn't change unless it meets your cost guidelines (which is free for a lot of people in your situation). If you have quality equipment (price and quality often go hand in hand - but it's not an absolute), then you won't see a huge difference. Especially in the situation you are referring to.

VOD, quite frankly is not particularly relevant as it's a buffer then watch technology. As long as you don't catch up to the end of the buffer this really won't have any impact on what you are doing. DECA's main advantage is a guaranteed slot on the line (bus) so that packets can be delivered in a timely manner and not delayed.

With Ethernet, there may come an occasion where packets flood your switch or get resent (for whatever reason) and this could delay the delivery of packets between DVRs resulting in less than optimal performance.

I'd never consider DECA for my non-DIRECTV equipment. The cost per port would be too high and the number of ports is too limiting.

So again, rather than pick nits on whether or not DECA is the right way to go, I'd suggest that you stick with your Ethernet setup that "has been rock solid." To me, this falls under the category of 'if it ain't broke, don't fix it.'


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## dennisj00 (Sep 27, 2007)

It's not a matter of believing, it's a matter of acknowledging that DECA was designed to be the most desirable installation for MRV and the D* installers.

There's absolutely no way that home networks could be supported for MRV -or whole home whatever.


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