An unsolicited message is when the PLC is the originator of a data message to an endpoint.
The endpoint is the destination of data message from the PLC. On the PC receiving the unsolicited message, the endpoint is a binding of the machines IP Address and a specific IP Port to socket. Endpoints must be unique and not in use by other applications.
An endpoint as it relates to NET.ABLINK 3.0 is an instance of the PeerMessage class. The PeerMessage class uses the IPAddressNIC and Protocol properties to bind the instance to a socket for your application to receive unsolicited messages. Therefore you're limited to a single instance of the PeerMessage class per IPAddressNIC and Protocol settings per PC. However, the instance of the PeerMessage class receive messages from a number of PLC's at a time. Below are a few examples of the typical configurations.
Example #1 - Receiving Unsolicited Messages on any network card.
In Example #1, a single instance of the PeerMessage class will receive unsolicited messages on network cards with IP Addresses 192.148.1.4 and 192.168.1.7
Example #2 - Receiving Unsolicited Messages on a specific network card.
In Example #2, a single instance of the PeerMessage class will receive unsolicited messages on network cards with IP Address 192.148.1.4 only.
Example #3 - Receiving Unsolicited Messages on separate network cards.
In Example #3, two instances of the PeerMessage class will receive unsolicited messages on network cards with IP Addresses 192.148.1.4 using CIP, while network card 192.168.1.7 receives CSP from PLC-5E and SLC 5/05.