Signal the transport to expect SASL frames used to establish a SASL layer prior to
performing the AMQP protocol version negotiation. This must first be performed before
the transport is used for processing. Subsequent invocations will return the same
{@link Sasl} object.
@throws IllegalStateException if transport processing has already begun prior to initial invocation
Signal the transport to expect SASL frames used to establish a SASL layer prior to performing the AMQP protocol version negotiation. This must first be performed before the transport is used for processing. Subsequent invocations will return the same {@link Sasl} object.
@throws IllegalStateException if transport processing has already begun prior to initial invocation