4. Resource Group Architecture : 4.2 Network Resources
   
4.2 Network Resources
For the vCloud resource groups, configure networking with vSphere design guidelines in mind. Increase the number of vSphere Distributed Switch ports per host to the maximum of 4096 to improve the scale at which vCloud Director can dynamically create port groups for vCloud networks. For more information about increasing this value, see the vCenter Server and Host Management Guide in the VMware vSphere Documentation (http://www.vmware.com/support/pubs/vsphere-esxi-vcenter-server-pubs.html).
Increase the maximum transmission unit (MTU) size to 1600 for all physical network devices and vSphere Distributed Switches in the transport network to support VXLAN or vCloud Director network isolation. Failure to increase the MTU size causes packet fragmentation, negatively affecting throughput of end-user workloads.
vCloud networking considerations are covered in Section 5, vCloud Resource Design.