This is the diagram that appears in the PRIME specification 1.3.6 showing the connection establishment process initiated by a Service Node. It shows how the Service Node sends a connection request to the Base Node via another switch.
The sniffer capture according to the above PRIME specification diagram is the following:
The other sniffer capture shown below shows the connection establishment process initiated by a Service Node but in this case, there is not any intermediate switch, so there are only 2 devices involved: the Base Node and the terminal or Service Node. The next image shows the connection establishment process with the 2 frames involved:
In order to obtain more details, if you go to the packet view, it is possible to find the type of messages and associate them with the previous diagram (In this case is a 4-32 connection):