Hello,
We have to implement a new LAN infrastructure for our new premises and would like to split voice and data traffic and give a certain priority to the voice traffic, using VLAN's and QOS. The LAN will host computers and IP phones, all servers are in a data center.
As I'm a VOIP newbie I've been reading quite some documentation but I am confused and hope someone can clear things up for me. The amount of information to go through is quite a lot and I would take less time if I'm pointed to the right direction, examples or documentation.
This is the hardware we have:
-1 cisco asa 5505
-4 cisco catalyst 3560 switches / 24Port POE / 100Mbit
-2 cisco catalyst 3560 switches / 24 Port POE / 1000Mbit
-20 Cisco 7940 series IP phones
-20 Polycom IP phones
. First of all, having an asa 5505 and 4 3560 switches with 100Mbit ports, what is the best way to interconnect the devices to have the best throughput? I thought of trunking all VLAN's on 1 port on the asa 5505 and then connect the first switch using a regular ethernet port, afterwards use the SFP uplinks to connect the other switches, but should I connect the switches in a chain or not?
cisco asa 5505 > SW1-1000mbits > SW2-1000mbits > SW3-100mbits > SW4... ??
> SW2-1000mbit > SW4
cisco asa 5505 > SW1-1000mbit ??
> SW3-100mbit > SW5 > ...
other option?
. Basically all switch ports should have both the inside and voice Vlan as we will use the ethernet port on the phone to connect our PC's. I was reading that to accomplish this I would have to configure the data Vlan as the native Vlan so the packes remain untagged but on the ASA 5505 i wasn't able to do this. Although the 5505 documentation explains how to do it I always get a "command not recognized" error marking the native word in the command. Looking on the internet I found this statement.
This switch port cannot pass traffic until you assign at least one VLAN to it. Trunk ports do not support untagged packets; there is no native VLAN support, and the adaptive security appliance drops all packets that do not contain a tag specified in this command.
(http://www.wr-mem.com/?p=58)
. Are there special considerations when using a mix of cisco IP phones and non-cisco IP phones?
. Regarding QOS, i have to use the auto qos voip trust command to assure that switches trust incoming packets that were already labeled by QOS on other switches. Should I do this on the asa firewall as well.
I hope I'm clear enough. Meanwhile i'm going back to testing
Thanks in advance
Martin
