What does ttyUSB mean? Sometimes, the embedded microcontroller does not come with a hardware USB interface. While it is possible to use a software-only USB stack, the additional constraints put onto the CPU and the usually small storage size often lead board designers to include a dedicated UART to USB bridge.
Because of a busy weekend I didn't really follow up other than via emails and this still hasn't been resolved. The consistent word from them was that porting a number sometimes takes 24 to 48 hours.. I spoke to a rep by phone today who promised it would be done within 2 to 4 hours.. It wasn't.
Port numbers are mainly used in TCP and UDP based networks, with an available range of 65,535 for assigning port numbers. Although an application can change its port number, some commonly used Internet/network services are allocated with global port numbers such as Port Number 80 for HTTP, 23 for Telnet and 25 for SMTP.