*Hi Ahmed, In addition to the to the points mentioned in other mails, for when and where should we use the QOS-GRP id's.
We specifically in an MPLS environment have to (necessarily ) use the qos-grp id's, when the exp value on the labels are different and we have a pop operation for the label, hence while queuing the packet on the exit interface we cannot use the newly exposed MPLS EXP value, so what we do is store temporarily the EXP value in the qos-grp id and make a decision in its accordance on the exit interface.we sometime as well use it to propagate the qos grp value to the EXP/Precedence to the newly exposed label on the exit interface. In case of Internetworkexpert's lab it has been used many time unnecessarily, may be just to make us learn!!! Thanks, Regards, Dara* On Tue, Jun 24, 2008 at 3:26 PM, ahmed mahmoud <[EMAIL PROTECTED]> wrote: > Good day All. > > I have something to add here.. I understand the usage of the qos-groups > but i don't understand why we need them?!! aren't the marking enough for > traffic categorization ? like DSCP , IP-precedence or the mpls exp bits !!! > . > > Ahmed > > On Tue, Jun 24, 2008 at 12:19 PM, JH Cockburn <[EMAIL PROTECTED]> wrote: > >> Hi M, >> >> >> >> Using qos-groups is not limited to PE routers only. In fact you may use it >> anywhere where you think it can make life easier… >> >> >> >> >> >> So the idea is that you can match certain packets and mark them in a >> certain qos-group and then later/elsewhere do stuff with the qos-group… >> >> >> >> For example match packets with a certain MPLS EXP COS value (on P router) >> and set them to a qos-group and later maybe shape or apply WRED based on the >> qos-group on another interface… >> >> >> >> >> http://www.cisco.com/en/US/docs/ios/12_2t/12_2t13/feature/guide/ftenpkmk.html#wp1090481 >> >> >> >> >> >> May also be used in IPSEC Configs: >> >> >> http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/gtqosips.html >> >> >> >> Hope this helps…. >> >> >> >> >> ------------------------------ >> >> *From:* [EMAIL PROTECTED] [mailto: >> [EMAIL PROTECTED] *On Behalf Of *mohamed hamed >> *Sent:* Monday, June 23, 2008 10:36 PM >> *To:* OSL CCIE Service Provider Lab Exam >> *Subject:* [OSL | CCIE_SP] QoS group >> >> >> >> Hi everyone, >> >> >> >> Does anyone know where we should use the QoS group on P or PE Router? >> >> >> >> As I understand that we usually use it on PE router, but I found some Labs >> on the internetwork expert use it on P router as well >> >> >> >> If anyone knows why we should use QoS grouo on P routers , please unicast >> me a mail back >> >> >> >> *Mohamed Hamed* >> >> *Network Consulting Engineer*** >> >> *Mobile** (KSA-Riyadh): +966543464502* >> >> >> >> >> >> >> >> ------------------------------ >> >> Introducing Live Search cashback . It's search that pays you back! Try it >> Now<http://search.live.com/cashback/?&pkw=form=MIJAAF/publ=HMTGL/crea=introsrchcashback> >> > >
