Before revision:  We introduce uTCP, an API extension that adds out-of-order delivery support without changing TCP 's wire protocol, by delivering received TCP segments to the application immediately on arrival along with sequence number metadata. To obtain robust out-of-order delivery across middleboxes that may re-segment TCP flows, the application employs a "record-marking" content encoding such as COBS, allowing the receiver to extract records from a byte stream with arbitrary holes.
After revision:  We introduce uTCP, an API extension that adds out-of-order delivery atop TCP and TLS. Small OS API extensions allow applications to manage TCP's send buffer and to receive TCP segments out-of-order delivery across middleboxes that may re-segment TCP flows, the application employs a "record-marking" content encoding such as COBS, allowing the receiver to extract records from a byte stream with arbitrary holes.