I am looking for input for deciding what managed network switch to buy for my network.
Details: We are currently running a fully gigabit environment on unmanaged D-Link gigabit switches. Out VOIP phone system (Microsoft LYNC with no PBX) and our data share the network. I have 25 users and about 70 servers on this network (we are software development). All of our users machines are Windows 7 professional 64 bit OS. Out Gateway is a Sonic TZ215 Firewall. Our LYNC phone system is fully hosted internally and we are using SIP trunks. Our computers are used as our telephones using the LYNC client as a softphone with all VOIP and computer traffic on the same IP range. Externally all of our voice traffic comes in over one Comcast 50MB company line and all data traffic comes through a second Comcast 50MB company line.
Problem: We are beginning to experience phone call quality degradation that I suspect is being caused by not having any QOS management with the current networking gear.
Goal: I want to put at least two layer 2 managed network switches in place to move the individual users computers to so that I can implement QOS for those computers used to make phone calls.
I am not well versed in layer 2 switch operation so am asking for some advice on what units to look at?