Generally, device redirection increases how much network bandwidth RD Session Host server connections use because data is exchanged between devices on the client computers and processes that are running in the server session. The extent of the increase is a function of the frequency of operations that are performed by the applications that are running on the server against the redirected devices. Printer redirection and Plug and Play device redirection also increases CPU usage at sign-in.
Parallels recommends to not allow device redirection if not being used since this will result in inefficient bandwidth usage. Local device redirection can be configured from Parallels RAS policies, registry, or Microsoft group policies.