Provisioning Services Tuning

1. Disable Spanning Tree or Enabling PortFast:  Improves performance and stability of the PXE process.
2. Disable Large Send Offload on PVS Servers and Target Machines to reduce timeouts to the PVS Server:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TCPIP\Parameters
   Key: "DisableTaskOffload" (DWORD)
   Value: "1"
3. Disable Auto Negotiation on all NICs involved to improve reliability and response of the PXE process.
4. Disable the Firewall services or open the appropriate ports.

Reference
http://support.citrix.com/article/CTX117374