An exchange of control records establishes a connection between two nodes that do not use the NPM. The initial signon record, sent by the “primary” node, is called an “I record”. The receiving node, or “secondary” node, sends a response signon record, called a “J record”. Extended NJE features exist and are acknowledged by the two nodes by setting bits in their respective I and J records.

Normal disconnection of an NJE node (using BSC or CTC protocols) occurs when the primary node sends a final signoff record, called a “B record”. In the SNA protocol, disconnection takes place when the primary node sends a CLSDST or when the secondary node sends a TERMSESS record.