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Anav
Sarcastic Llama? Naw, Just Acerbic
Premium
join:2001-07-16
Dartmouth, NS
kudos:4
reply to OGalati

Re: IPTV Possible on USG??

Listen, just because Messi Plays for my fav team Barca, does not mean I have to agree with you. Furthermore HOWDARE (joder) you side with that upstart JP obviously hiding in Norway for some reason, instead of a fellow American (you know that North and South American free trade and bonding).

You are partiallly correct. The switch does do vlan tagging and actually changes the data packets. However, I disagree with respect to 802.1p. the Switch does not actually tag packets, but concur it can read them but read on..........

The switch according to how I read the manual.
a. has a mapping table of its priority values physical queues to the standard values 802.1p (this table is strictly for the user to to be able to setup the zyxel values IAW with how they want actual 802.1p packets to be handled and has no actual taggin function just a translation function)
b. the switch knows what the physical priorities are as assigned by the admin. These will be applied to port traffic or vlan traffic.

Now two cases can occur when a traffic arrives or lets say egresses an interface.

(i) It has an 802.1p tagged data
Here the switch which can read the tagged data point but does no direct physical function based on 802.1p. Instead, the switch then uses the mapping table translates it to the physcal queue setting that the user admin put for that 802,1p level ABD THEN ensure proper priority routing. - the switch then treats or maniuplates that data according to the user schema.

(ii) It has no 802.1p tagged data
Here the switch is screwed because no Tagged data is detected.
Luckily the admin has defined a default setting for such data. The switch detecting an untagged packet goes to its admin setting and sees a priority default has been enabled (for that port or vlan) and then applies one of the zyxel PHYSICAL security priority queues to that data. It does not tag it, it simply maniplates it, ie prioritized it internally IAW with the rest of the traffic as per the admin priority routing table.

In both cases above its not the 802.1p that manipulates the datas through the switch in terms of priority. It is the zyxel priority physical queue settings which determine traffic priority flow. If the data is tagged, the switch reads it translates it and then carrys out actions. If untagged, the switch apples a default and carrys on.
--
Ain't nuthin but the blues! "Albert Collins".
Leave your troubles at the door! "Pepe Peregil" De Sevilla. Just Don't Wifi without WPA, "Yul Brenner"

LlamaWorks Equipment



Anav
Sarcastic Llama? Naw, Just Acerbic
Premium
join:2001-07-16
Dartmouth, NS
kudos:4
reply to Anav

Im still waiting for Proof. You know those jpegs that JP is going to post showing an untagged packet arriving at his switch and then the next showing a data packet now tagged with 802.1p level four. No cheating allowed (like using a cisco switch LOL).


JPedroT

join:2005-02-18
kudos:1

3 edits

I think you need to revisit some stuff here, because a switch can have more or less queues than there are p bit values.

So you need to define which hardware queue that should get your frame with p bits xyz and abc and ghj etc etc.

The next point, what is a queue? Its just a memory buffer where we store frames and can select which frames should be sent out in which order, based on what you ever disciplines your switch supports SFQ, RRB and WRRB etc. And we use multiple queues to "sort" the frames, the better your switch the more queues you have.

I can definitely do some traces, but it wont happen very quickly. Since I drowning in work, the Chinese New Year week is a week I might be able to get some head way into my pile of backlogged tasks

And of course »www.ingress.com/ takes up a lot of my spare time

--
"Perl is executable line noise, Python is executable pseudo-code."



Anav
Sarcastic Llama? Naw, Just Acerbic
Premium
join:2001-07-16
Dartmouth, NS
kudos:4
reply to Anav

Too funny JP. I was just thinking that since your so rich, you should fly me to Taiwan and we can meet and discuss the switch architecure at the Poodle Park ( I cant pronounce it properly) where zyxel hq resides. No worries mate. Take your time. Avoid the beer bath, less likely to drown although I hear its really good for the skin.


JPedroT

join:2005-02-18
kudos:1

Why do you want to go to Taiwan?

And if I was rich, I would have been able to tell somebody to do the test and I could post and claim the credit


Kirby Smith

join:2001-01-26
Derry, NH
Reviews:
·Fairpoint Commun..
reply to Anav

May I try to blow some fresh air through the llama intransigence and suggest that in order for prioritization to be useful, a managed switch has to set the priority bit for the router to know that QoS is wanted. How could a router otherwise achieve the priority goal? It is my expectation that any reasonably useful managed L2 switch will set the bit, no matter how awkwardly the user manual is written. Whether a particular application actually needs QoS to achieve functionality is another question.

kirby



Anav
Sarcastic Llama? Naw, Just Acerbic
Premium
join:2001-07-16
Dartmouth, NS
kudos:4
reply to JPedroT

said by JPedroT:

Why do you want to go to Taiwan?

And if I was rich, I would have been able to tell somebody to do the test and I could post and claim the credit

Ha, the Taiwan was merely bait. Now that I know your ready and willing to pay me to go to elsewhere, suggest Valencia is nice this time of year.

JPedroT

join:2005-02-18
kudos:1

You stopped reading after the first sentence?



Anav
Sarcastic Llama? Naw, Just Acerbic
Premium
join:2001-07-16
Dartmouth, NS
kudos:4

Just testing how much free time you really have. Could of traced 5k untagged data packets by now .