What is Quality of Service?

[spidey07]

This term seems to be thrown about - QoS! But I've got QoS! Network Neutrality for all!!!

There seems to be a severe disconnect between quality of service in the SOHO world and this yields a "my packets are more important than yours!". This is called priority queuing, it was the was the way things were done in 1998. It did it's job, poorly.

So for me Quality of Service means:
1) Guarantee provisioned services:

That's it. It's short, but should provide good discussion.

 

[ScottMac]

That's pretty much my understanding as well, QOS/COS guaranteed by virtue of tags in packets and / or flags in the frame header and / or contract per PVC (CBR, VBR, ABR, UBR).

 

[dandragonrage]

It means "My WoW is more important than my torrents." And DD-WRT sucks at it without console voodoo done, by the way.

 

[JackMDS]

It is like the term GT in cars.

It started to indicate special cars, and once it took hold, every manufacturer started to name few if its "Sardine Cans" GT.

Similarly in the End_User Networking market the developer feel free to adopt terms as they choose regardless of the initial consensus when the terms "coined" long time ago.

 

[kevnich2]

Originally posted by: dandragonrage
It means "My WoW is more important than my torrents." And DD-WRT sucks at it without console voodoo done, by the way.

I really don't think you have any idea what you're talking about. I have no problem if you personally don't like DDWRT and prefer another firmware but don't go around saying that DDWRT cannot do the same thing as your preferred firmware without messing with console commands. That is very false information.

 

[dandragonrage]

Show me DD-WRT being this advanced http://www.polarcloud.com/img/ssqosc108.png http://www.polarcloud.com/img/ssqosg108.png

 

[spidey07]

This is a technical discussion, can we keep it that way instead of screenshots?

 

[jlazzaro]

To me gauarantee provisioned services screams RSVP...you may be reserving the need resources along the entire path, but at what cost? I think of per hop behavior more than anything...mark a packet to your hearts content, once it leaves your management domain there are no gauarantees.

With voice and video becoming more and more prevelant, choosing a provider that trusts these markings end to end is crucial.

 

[Pulsar]

Does it really mean permanently reserving, or setting aside that bandwidth? I've always seen that as wasteful. Wouldn't a better QoS be one that gives the bandwidth when needed?

I've got routers that do it both ways, BTW. My voip router sets aside the bandwidth and won't let anything but voip touch it. My buffalo with tomato firmware prioritizes based on traffic type, and sets aside nothing.

 

[ScottMac]

Originally posted by: jlazzaro
To me gauarantee provisioned services screams RSVP...you may be reserving the need resources along the entire path, but at what cost? I think of per hop behavior more than anything...mark a packet to your hearts content, once it leaves your management domain there are no gauarantees.

With voice and video becoming more and more prevelant, choosing a provider that trusts these markings end to end is crucial.

There aren't any. Providers can only control the resources within their domain. There's a better-than-even chance that your traffic will leave your provider's network and all QOS/COS marking goes out the window.

That is the advantage that using VoIP (for example) from the provider (Verizon, AT&T) versus a third-party (like Vonage) ... they can put the gateway resources on their network and give a higher Class/Quality of Service to the VoIP packets and offer a more stable service.

 

[jlazzaro]

Originally posted by: ScottMac

Originally posted by: jlazzaro
To me gauarantee provisioned services screams RSVP...you may be reserving the need resources along the entire path, but at what cost? I think of per hop behavior more than anything...mark a packet to your hearts content, once it leaves your management domain there are no gauarantees.

With voice and video becoming more and more prevelant, choosing a provider that trusts these markings end to end is crucial.

There aren't any. Providers can only control the resources within their domain. There's a better-than-even chance that your traffic will leave your provider's network and all QOS/COS marking goes out the window.

i wasnt trying to say any different, but if you never have to leave the providers control then you have no worries that was my point...to choose services like MPLS and the like where end-to-end QoS is a reality.

 

[SpunkyJones]

Originally posted by: jlazzaro

Originally posted by: ScottMac

Originally posted by: jlazzaro
To me gauarantee provisioned services screams RSVP...you may be reserving the need resources along the entire path, but at what cost? I think of per hop behavior more than anything...mark a packet to your hearts content, once it leaves your management domain there are no gauarantees.

With voice and video becoming more and more prevelant, choosing a provider that trusts these markings end to end is crucial.

There aren't any. Providers can only control the resources within their domain. There's a better-than-even chance that your traffic will leave your provider's network and all QOS/COS marking goes out the window.

i wasnt trying to say any different, but if you never have to leave the providers control then you have no worries that was my point...to choose services like MPLS and the like where end-to-end QoS is a reality.

MPLS works for site to site communications across the same telco, but a carrier cannot not terminate all voice or data traffic onto their network, it needs to exit the network. As long as you are calling Doris in accounting at the Topeka office, you'll be fine, but your screwed if you call home to the wife.

 

[spidey07]

Originally posted by: jlazzaro
To me gauarantee provisioned services screams RSVP...you may be reserving the need resources along the entire path, but at what cost? I think of per hop behavior more than anything...mark a packet to your hearts content, once it leaves your management domain there are no gauarantees.

With voice and video becoming more and more prevelant, choosing a provider that trusts these markings end to end is crucial.

RSVP would be nice, don't know how widely it's deployed. But if provisioned services can't get through I'd call that a provisioning problem as well. AFAIK, no provider will trust DSCP markings from another but I believe that is starting to change and needs to IMHO. That's where it gets sticky - what's to stop one provider from marking all their stuff express forwarding?

For now per hop behavior works really well. It also allows providers to offer their end customer media rich services like packet voice/video.