A process of using a cache of outgoing packet identifiers to recover from a protocol error includes assigning a receive identifier associated with a user entity to a traffic stream at a receive node. The receive identifier is sent to a transmit node. The transmit node is instructed to associate the receive identifier with a receive plurality of data packets of the traffic stream. The transmit identifier associated with the user entity is assigned to the traffic stream at the transmit node. The transmit node identifier, the receive node identifier, and the address of the receive node are stored in a transmit cache at the transmit node for each of the receive plurality of data packets. The receive plurality of data packets is sent from the transmit node to the receive node. An error message is received at the transmit node from the receive node, indicating that the receive identifier was not recognized. The transmit cache is searched for the transmit node identifier using the receive node identifier and the address of the receive node. The user entity associated with the transmit node identifier is identified, and the user entity is removed.