QoS /VLAN's basics using Cisco devices?
Posted on 2008-11-13
I do not know much about QoS and how it works. Our company is growing and we are in phase of implementing Wireless which in turn will support both VoIP and data. Currently we running VoIP in our environment but there are no VLAN's or QoS configured at all. Everything runs on default VLAN. In order to plan and design our new netowork i have few questions:-
// Lets say we have a cisco 2960 layer 2 switches spread all over and a Cisco ___ layer 3 switch as our core switch//
1. QoS:- Does the priority take place at the core layer 3 switch or the layer 2. Say if a packet enters a 2960 switch will it first go to the layer 3 switch and then gets prirotised or does it gets pririotised as soon as it enters the 2960. And how does this happen? (please do not refer to cisco pages because to understand QoS there is too hard for me)
2. QoS:- If 2960's can do QoS on there own why will we need to get a layer 3 switch?
3. QoS:- Prioritisation take place on what basis ? Is it protocols or ports ?
4. QoS:- If i enable "auto qos voip" on the ports connected to the phone and "auto qos trunk" on my trunk links, does it mean my QoS is running in full and i dont need to fiddle with anything else?
5.QoS:- "auto qos discovery" which switches support it and please please suggest a layer 3 switch which will suite my environment.
6.VLAN's:- Finally, will it be worth to put the VLAN's in place even if you are running the QoS. I know they are totally different concepts but ours is not a very big environment say about 100 computers and about 50 phones.
I know too many question's :-) ,any answers will be highly appreciated. Thanks!!