QoS with Unmanaged switch

[Spztc1]

We are creating a temporary setup for one of our locations.   There will be a primary PoE switch but inorder to reserve data drops we will be using 5 to 12 port unmanaged switches to extend connectivity to multiple desk.  The unmanaged switches do not supply PoE so we will be using power adapters to power up our 6915 Mitel phones.

Using the unmanage switches with the Mitel 6915 VoIP phones and 3300 controller, could we experience Quality of Service issues with our calls?

Thank you

[Dogbreath]

Maybe? Maybe not? It depends on how heavily loaded your LAN is, which nobody here knows the answer to.
In my experience, LAN bandwidth is very cheap compared to WAN bandwidth. I have never bothered with QOS on the LAN, and focused my attention on managing WAN bandwidth instead.