The use of Protocol Enhancing Proxies and HAIPE encryption has traditionally been mutually exclusive. Prior to coming back online the application is configured with information to allow it to run on the new site without having to perform the configuration actions after the application has come online. In addition, the opacity of the opaque quartz part to flash light is determined to fall within an appropriate range based on the material or thickness of the opaque quartz part, taking into consideration the composition or thickness of a thin film formed on the substrate and various conditions concerning the energy of the irradiation light during flash light irradiation or the like. The expanded core may be incorporated into the entire length of the optical fiber or in a transition section of a fiber that also comprises a basic core portion having a basic core radius.