How to choose between Cake and Adaptive\Flex QoS

[nikr]

I was not able to find up a prior discussion, so thought I'll ask. Is there a general recommendation on how to choose one over another? The way I understand cake is better then fq_codel which is used by adaptive but Adaptive also does some DPI for prioritize voice/video along with some other apps where as cake relies on some priority bits to be set appropriately by the apps??, which may not always be the case. Also cake makes sure that none of the clients are starved which may mean that your 4K stream might suffer in case of congestion. Also cake is easier of CPU so it might be better option for routers which lack in processing power.

So Use Cake if

• Lower power devices
• Want to make sure that no device is starved

Use Adaptive/Flex QoS

• If you want your preferred class traffic not to be impacted by congestion

Anything else I am missing?

 

[dave14305]

Also cake is easier of CPU so it might be better option for routers which lack in processing power.

Cake does a lot more processing (nat, diffserv, wash, etc.) so I would expect it to use more CPU depending how it is configured.

Cake is usually recommended for lower bandwidth connections (less than 350 Mbps) because most consumer routers don’t have the processing power to shape at higher bandwidths. Cake requires HW acceleration to be disabled, so it is more easily constrained by CPU than Adaptive QoS.

But Cake is set-and-forget. So is Adaptive QoS. FlexQoS allows for never-ending tinkering that eats up your life, however.

 

[MvW]

If there's anyone who's working on both, it's @dave14305, so I guess he'll be your best bet to answer your question.

Edit: Well, look who just showed up while typing...

 

[nikr]

What I am struggling to understand is how will Cake QoS decide to prioritize 4K stream over say File download. I understand that it can look at TOS/DSCP bits, but whose responsibility is to set those bits, what if it is not set.

 

[dave14305]

What I am struggling to understand is how will Cake QoS decide to prioritize 4K stream over say File download. I understand that it can look at TOS fields, but whose responsibility is to set those bits, what if it is not set.

Without the application setting TOS/DSCP, it won’t really prioritize as much as ensure fairness among all active flows within a tin. A flow is identified by protocol, source address, source port, destination address and destination port. So a 4K stream from Netflix will be different from a large file download, because that combination of IP and ports are almost guaranteed to be different from each other.

Then you have to consider flow isolation options like dual-dsthost, triple-isolate, etc. This determines how the available bandwidth is doled out to competing flows.

It’s very complex so that you don’t really have to worry about it.

 

[nikr]

Without the application setting TOS/DSCP, it won’t really prioritize as much as ensure fairness among all active flows within a tin

And this is what I am worried about. I am sure CakeQoS is going to be fine 95% of time, infect I am sure I don't even need QoS 95% of time. Its that rest of the time when family and friends are over and we decide to play some game or watch a movie.

Anyways you are right, I should not worry too much about how it works if it works.

 

[Morris]

What I am struggling to understand is how will Cake QoS decide to prioritize 4K stream over say File download. I understand that it can look at TOS/DSCP bits, but whose responsibility is to set those bits, what if it is not set.

Cake dose not look at TOS/DSCP flags when configured to use besteffort. Rather it measures how much bandwidth an stream is consuming and slows the hogs such as downloads. A 4k stream will consume 20 to 25 Mb/s while a download will consume everything it can and therefor be slowed to allow the well behaved 4k video stream to get it's needed bandwidth.

As far as when to use Cake v Adaptive\Flex, if you want to set up QOS, have it work all the time and not have to keep tinkering and never be done one should chose Cake. Cake will fail on an over subscribed link. Adaptive\Flex which is rule based could allow your highest priority (most important) applications to continue to function while other don't when there is not enough bandwidth. Good luck getting along with others sharing the network if you are the master of an oversubscribed WAN link that uses Adaptive\Flex. If you link is over subscribed then there is only one solution and that is to provision more bandwidth. Cake is as easy as cake and just works.

Morris

 

[Tech9]

Anything else I am missing?

With fast enough ISP - No QoS. You don't have to choose between QoS options, if you don't need QoS.

 

[Simon W]

With fast enough ISP - No QoS. You don't have to choose between QoS options, if you don't need QoS.

In the interest of preventing bufferbloat, isn't QoS always useful even on the fastest of connections (assuming chosen QoS + hardware is capable of matching the bandwidth available)?

 

[Morris]

If you are not having problems, bufferbloat don't matter. A little bit is OK. It's when your link is stuffed and you are constantly dropping packets that it matters. Slowing down the bandwidth hogs is what is needed to allow the other hosts to have a good experience. Cake QOS makes this super easy. Any QOS scheme will work yet will take more effort. If you link is not full, then QOS dose nothing and CAKE can be harmful to fast links as hardware acceleration is disabled which will prevent the router from being able to run at the full speed of the link.

Morris

 

[coxhaus]

In this day and age, you just buy a faster internet over running QoS. It is a much simpler solution for home use.

In enterprise land you will end up running QoS but let someone pay you to do it.

 

[Tech9]

In the interest of preventing bufferbloat, isn't QoS always useful even on the fastest of connections

In general there is no bufferbloat if the ISP line is under saturation speeds. Even if you have QoS running, it's doing nothing.

 

[Smokey613]

In this day and age, you just buy a faster internet over running QoS. It is a much simpler solution for home use.

In enterprise land you will end up running QoS but let someone pay you to do it.

Unless you do not have access to faster internet, then you make do with what you have.

 

[Tech9]

Your Fiber 100/100 is perfect, @Smokey613. Your browsing experience is the same and your latency is better than 1000/30 Cable.

 

[Smokey613]

Your Fiber 100/100 is perfect, @Smokey613. Your browsing experience is the same and your latency is better than 1000/30 Cable.

It is very "smooth" as far as browsing, streaming, etc. more so than the 100/10 cable. Right now I am not running any type of QoS and it works fine.

 

[Tech9]

It is very "smooth" as far as browsing, streaming, etc.

Do you want it better?

1x TL-SG2008P
1x OC200
2x EAP620HD

Giving you some ideas for the next signature update.

 

[Smokey613]

Do you want it better?

1x TL-SG2008P
1x OC200
2x EAP620HD

Giving you some ideas for the next signature update.

LOL !! I think I had better stop for now.... my wife was already complaining about all my network tinkering.
The CL fiber works great, the only issue is they have a tendency to bury their stuff a little shallow, so it sometimes gets dug up by contractors. Our neighborhood is still growing so a lot of construction right now.

 

[Morris]

In this day and age, you just buy a faster internet over running QoS. It is a much simpler solution for home use.

In enterprise land you will end up running QoS but let someone pay you to do it.

In this day and age, I right size my link and use QOS for download hogs and not give my funds to an ISP that is already rich. One could purchase a router or two a year using your method or take the family out a few times.

Morris

 

[Tech9]

One could purchase a router or two a year using your method of take the family out a few times.

Yes, but you can't show good speedtests to others.

 

[Morris]

Yes, but you can't show good speedtests to others.

Ya, I can show them green backs!

Morris