220.127.116.11.6 OUT_R1/A3 or OUT_R2/A3 RTS PDUs
An outbound proxy implementation MUST NOT accept either of these RTS PDUs in any state other than Open_Start. If they are received in any other state, the outbound proxy MUST treat these PDUs as a protocol error as specified in section 18.104.22.168.14.
If either of these RTS PDUs is received in the Open_Start state, the outbound proxy implementation MUST retrieve the virtual connection cookie from the OUT_R1/A3 RTS PDU and search for a matching cookie in the virtual connection cookie table. If found, it MUST execute the sequence of steps specified in section 22.214.171.124.6.1. If not found, it MUST execute the sequence of steps specified in section 126.96.36.199.6.2.