Assuming the message(s) are interpreted, the following values provide a two way instant communications for our civilization and the ETI civilization:
1. It addresses the timescales comparable to human lifetimes or at least the longevities of human institutions.
2. Long interactions can take place with long messages as opposed to potentially short “we exist” announcements.
3. The interaction may result with a meaningful relationship to progress to new initiatives and developments.
The issue with two way instantaneous communications is firstly the sudden urgency to decipher a signal and rapidly respond.
It would be expected that an ETI civilization would be more advanced than us because of this method of communications. It would confirm ETI civilization are using QSC as well and open the possibility of other ETI civilizations using the same method.
It would be no surprise that the first contact may open the existence to a group of civilizations already in communications. The communications may happen by eves dropping on any civilization. It could be two way communications between themselves. The length of duration of time to listen into the communication may provide enough time to understand the information and be ready with the first response.
We would initially respond with a ‘holding signal’. This means sending there signal back to them with a slight modification that would be recognised by them as intelligent. In the hope that a second signal comes from them, we would be a position to further interpret there language, thereby improving on our first signal. The aim would be a constructive relationship with them.
The message may arrive in different forms. This means anticipating and simulating each type of form. Because of the urgency of responding, simulated messaging campaigns would be required in order to be confident for the real contact event.
The contact team required for QSC would be on standby with different disciplines. For example, language interpretation, socio cultural understanding, preventive maintenance of all communications hardware and software so that it is sustainable over a long period of time.
ETI may want constant and sustainable communications; in this scenario, scientists would have to operate on 24 hour cycle in 8 hour shifts.