Technical: QoS setup for STB when NOT using Actiontec DHCP
ak46
Enthusiast - Level 3

This is way over the heads of the phone support people so I thought I would post here and see how it goes.

I run a Server 2003 domain at home.  When I had FIOS TV installed we were not able to get the STBs working properly without reseting the Actiontec to defaults and using it for the DHCP server.  This caused many problems with my domain member PCs and I ended up having to statically address them.  Unfortunalty, the DHCP server in the Actiontec is terrible and Ive had to reboot the unit several times when my PS3, PSP, Wii, and other non-domain/non-static devices connect,  (It also affects the STBs at times and both the router and the STBs end up needing reboots.)

After a bit of looking and a bit of experimenting I was able to disable the DHCP on the Actiontec and go back to DHCP on the Windows Server.  My domain is working great again.  The STBs are working great (although you HAVE to create reservations that give them IPs starting with 100 or the will NOT work).  All the other devices get IPs quickly and work everytime.  Yeah!

Now for my question.  When the Actiontec was assigning the IP, the STBs seemed to automagically get a QoS setup in the Actiontec router.  When the Windows Server assigns the IP there is no QoS setup to be found.  While I understand why this occurs, I really don't know if there will be an adverse side affect.  On demand seems to be working fine, but I don't use it much and don't know if I'll have issues when the "network" is experiencing congestion.  If the QoS setup is important, can anyone give me the details on how to implement the setting manually in the router?

Thank you...

-ak 

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Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
G-Pon
Contributor - Level 1

Good work AK, you have my TOTAL respect!

I have always assumed (though it is JUST an assumption, I don’t work on this part of the network) that the Verizon router firmware keeps the STBs high in policy hierarchy. The scheduling of packet distribution as administered by Windows Server would have no hard-coded STB bias, or quality reporting back to Verizon to trigger load balancing, etc. other than that there’s no down side I can see, you have accurately pinpointed the risk: “don’t know if I’ll have an issue when the ‘network’ is experiencing congestion”.

Another potential risk of non-Actiontec/Verizon-firmware-managed packets/traffic is the  logs, if the Actiontec router and/or STB’s have to use processing resources to log events, this could effect the performance over-all of the device(s). This might not show up right away, but if as size of the logs balloon over time performance might degrade. I have seen the routers suffer from this, a re-set fixes it (clears the logs). You can disable router logging in the Actiontec too. I donn't think the STB’s do AS much logging, but I have seen symptoms on STB’s that could be attributed to this, so keep an eye out for it.

Incidentally, you should use the Actiontec router’s option to save the configuration (file) you have gone to so much trouble to create if you have not already done so.

(and thanks Techman for your input on this part) The STB’s need an IP range reserved for them of: 192.168.1.100 thru 192.168.1.110

To answer your main question directly, no, there is no way to customize the Actiontec TCP/IP protocol stack further that I know of. Now, it’s been a while since I took THIS class, but I’m pretty sure the policy store for QoS has to come from the Windows Active Directory device in use, now yours, maybe since a QoS/ACS server pulls it’s configuration information from Active Directory I think configuration information for STB’s might be cacheable there 

QoS could be more of a factor in future uses of this technology like .avi files or PC games streamed from your PC to the TV from a slow performing computer for example.

Message Edited by G-Pon on 02-11-2009 11:08 AM
Message Edited by G-Pon on 02-11-2009 11:22 AM
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Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
ak46
Enthusiast - Level 3

G-Pon,

  Thanks for the reply.  I did have logging set as low as possible.  (The Actiontec UI is a bit difficult to find all the places where logging setups are maintained however...so who knows if I missed something.)  I know for a fact that I saw specific entries on the QoS screens when the STBs picked up their IPs from the Actiontec directly.  I may try and switch back, take screen dumps and a config backup of the QoS setup and see if I can re-create it manually after another switch back to Windows DHCP.  (Too bad I didnt think to do that before all the work!)

  The Actiontec definitely does some things behind the scenes that are not configurable from the UI that is specific to Verizon's needs.  For example, when I decided to use the DVR web access, a non-removable inbound port forward was defined.  You can see it in the GUI, but no delete icon for it.

  As for your statements on QoS....Im not sure what you are thinking.  It doesn't sound right at all.  I'm assuming that the STBs do DSCP packet marking for video traffic.  (I can put a sniffer on my LAN to verify....but I'm sure its true.)  If there is no QoS policy defined on the router, it sends all traffic accross its interfaces with the same priority.  If there is a QoS policy, then it will give priority to the tagged traffic.  It really has nothing to do with how the device gets its IP address.

  All that said, I do have another concern.  I have 20/5 Internet service as well.  My understanding is that the video service from the STB does not use this bandwidth, but some other pool of bandwidth thats part of the FIOS TV service.  Is this true?  Will the fact that these devices are using IP 100-110 alone be enough to not steal away from the 20/5?  (Which lately it seems actually runs FAR slower.....and this was before my changes.  Seems like my area might be getting over subscribed.)

  Thanks again for the feedback....

-ak

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Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
G-Pon
Contributor - Level 1

Oh yes, the data traffic/QoS stuff has no bearing on the IP addresses of the STB’s, I mentioned it (perhaps not-separately enough) in case others who see the post wish to stand on your shoulders and do this too, you were a little non-specific on the full IP range for the STB’s.

There is PLENTY of bandwidth left on the light, the over-subscription issues of previous technologies don’t apply here.

The other observation/question you pose is valid however, “Will the fact that these devices are using IP 100-110 alone be enough to not steal away from the 20/5?” in a word no but we account for that, the VOD, Widgits, and TV guide use the data spectrum of the light (1490 nm), not the video one (1550). The performance relationship between VOD and data download to a PC is possible in theory. To prevent that theory from becoming reality and impacting your data download the over-all provisioning for your 1490 (data) is actually 30 at the ONT & OLT, & so on upstream, not 20. The extra 10 set aside for VOD, Widgits, TV guide etc. Only the most extreme use would impact the typical customer. (I am the first to concede you are not the typical customer).

To put it simply, if you exceed your reserve 10 you could begin eating into your 20.

Does your removal of some of the management of traffic from the Verizon router impact this built in fail-safe? Hmmm, let me look into it.

Keep a test site handy like www.speedtest.net to be sure the drop is not severe (again, mentioned more for other viewers AK, not you, you're probably already doing this). One of us can, given the account information, be sure the extra bump on the 1490 (data download) is allocated at the ONT as it should be, if speed tests drop significantly below 10 or 15 % of 20 it should be looked at.

I thought about mentioning putting net-mon on the task, but without being able to monitor a sniffer loaded on all the devices involved, the results might be a little less conclusive.

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Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
ak46
Enthusiast - Level 3

G-Pon,

  I wish to comment a little more on "There is PLENTY of bandwidth left on the light, the over-subscription issues of previous technologies don’t apply here.".  There is a SIGNIFICANT impact to the bandwidth tests (using speedtest.net) during the evening surge.  I generally use the NY test site and mid-morning I will generally see 17-18Mb, but in the evening 6-8pm EST I am lucky to see 9Mb.  Granted, this might be due to a segment out of Verizon's control somewhere in between, but generally every access to the Internet is quite a bit slower during these times.  So even if not all Verizon's fault, from the average customers point of view the experience is not much different than with other providers.  Given this Im not sure how you can state that a customer shouldn't see more than a 10-15% drop in results to speedtest.net....I think the vast majority of people who test using that site is going to see drops WAY more than that during peak usage times.  Now if Verizon had a test site similar to speedtest.net on its own network, I would agree with you.  speedtest.net is public Internet so I don't know how you can say this.

  As for the impacts so far because of my particular setup....I  have not seen an impact to VOD quality with or without the QoS setups in the router.  I also have not seen any impact to bandwidth tests while VOD is being used....even HD VOD.  I have not tried to saturate the VOD traffic, but then again I only have two STBs with VOD capability....it should be able to keep up with that no problem.

  I appreciate your tech description of how the spectrum is used, but I knew video was seperate from data.  I never had any fear that normal TV would be impacted by these changes I've been making.

Thanks again for your answers and investigation....I appreciate you looking into the impacts of not using the Actiontec for DHCP.

-ak

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Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
tsk
Enthusiast - Level 3

I have done some preliminary testing.

To start, I would agree that you probably don't need to worry about it. But if you want to be sure or just want the comfort:

The heavy traffic would be inbound for VOD.  Verizon does indeed seem to tag VOD traffic with DSCP 4 priority.  The actiontec should already be prioritizing this properly but if you have your own router in the mix as well it would need to do similar.  This is particularly true if the AT is not your primary router.

I also don't believe the STBs or the AT will tag outbound traffic so QoS would not apply there.  It would strictly be downstream.

The one thing the DHCP server on the AT does for STBs is to provide DHCP option 125 info in its OFFER, in response to STB requests that include DHCP option 60 (Vendor Class Identifier=IP-STB).  This pretty much just defines the AT as the CPE management gateway for the STBs, and it doesn't seem to really be needed for normal functionality.  The reason the STBs end up with their own IP range is that they are assigned from a different DHCP scope that includes the Option 125 bits.

Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
ak46
Enthusiast - Level 3

tsk,

  Yup....that explains how it know to address them with 100-110, but also explains why I saw a QoS setup for them when using the AT for DHCP.  This weekend Im going to switch back to AT DHCP and make note of what I see.  I know Im not crazy, there was something there, I just didn't think to write it down before I made the changes.

  I am also in agreement that these change most likely will NOT affect VOD unless something else has gone wrong.

-Andy

Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
G-Pon
Contributor - Level 1

You’re correct of course, the other hops along the way will have their own limitations on bandwidth completely outside Verizon’s control, or yours. Verizon does have a similar site, here is my entire collection:
http://speedtest.verizon.net/SpeedTester/help_speedtest.jsp/fttp
http://ciseweb100.cise-nsf.gov:7123/
http://infospeed.verizon.net/fttp/
http://dallasfsc.verizon.com/tx_web/data_speed_guide.asp
www2.verizon.net/micro/speedtest/
http://www.speedtest.net/
I usually use the 3rd party site for customers as it is more user friendly

I am pretty sure, but not absolutely sure, that the Verizon speed test tool uses the same methodology as the other ones, not Vz-to-Vz captive. I can’t accurately test from here to cite any differences, but please try the Verizon ones.

Think I heard a news report recently that there’s a known nationwide after school speed drop. Nothing much any of us can do about that except send the kids outside to play. Apparently many businesses now time batch-runs and other mission-critical activities before school lets out!

Oh! And there’s a hot-fix for Vista speed issues, check out:
http://support.microsoft.com/kb/939006
for your Vista machines and then maybe the server version you’re on may have some similar hard-coded MTH limits in a security patch or something (like Vista does without this MSFT hot-fix). It’s been a while since I did server support but it’d be worth checking on.

But enough on speed, that’s secondary to our string…

On the risk of non-Verizon router DHCP to STBs…

We agree with you and tsk, & the best advice I can get is that the allocation of DHCP duties to a Windows Server would not impact the isolation of the “reserve 10” from the “data 20”, that alone would not impact the 20 download’s available bandwidth.

The router though, remember is now just a “switch” and will behave that way. No Firewall, etc. The brain-trust here wanted me to remind you (and again, anyone else who clicks-in & wants to try this) appropriate security measures should be undertaken to replace those native to the router’s default state.

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Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
alange1
Newbie

I, too, had my network DHCP served locally, but it wasn't on the 192.168.1.0/24 subnet.

> The STB’s need an IP range reserved for them of: 192.168.1.100 thru 192.168.1.110

Is there something "magical" about this range, or could I use any of the RFC1918 address space? Will  addresses for the STBs in the 172.16.5.100-110 range work?

In my DSL setup, the router was statically assigned 172.16.5.1 and used as the gateway, then DHCP and local DNS was served from a local machine to the rest of the network.

Thanks

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Re: Technical: QoS setup for STB when NOT using Actiontec DHCP
ak46
Enthusiast - Level 3

alange,

  I also used a different address space before I got FIOS TV.  I HAD to switch to the 192.168.1.0/24 subnet in order to get the boxes to work.

-ak

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