Access port strictly accepts untagged packets (no vlan info) from the device connected and adds a vlan tag to the incoming packet to be processed in the switch/router. Any packet destined for the device connected to the port will have its vlan info removed. So the port would be considered an untagged member of vlan Trunk port strictly accepts tagged packets. If the port is a tagged member of a vlan it allow that traffic to pass. General mode is a hybrid, it allows both worlds to happen. You can add the port to any vlan as a tagged member and it will pass that traffic tagged to and from the port. But you also get the ability to have the port be an untagged member of 1 vlan which it can pass traffic to and from untagged. This is controlled by setting the PVID value for the port. https://www.dell.com/community/en/conversations/networking-general/port-modes-access-vs-general/647e97e5f4ccf8a8de001eeb?commentId=647e97f4f4ccf8a8de016bac