PortStore5 features a 4 MB internal flash memory for RS-232 data capture.
Stored data can be retrieved when the LAN connection is re-established. Remote serial port can be accessed in Windows as a Virtual Serial Port.
WEB-based configuration and full RS-232 serial port (9 pins).
http://new.hwg.cz/device/portstore5-0
PortStore5: RS-232 to Ethernet with logging
PortStore5 connects a full RS-232 or RS-485 serial port to a LAN.