From: Comparison of approaches for intrusion detection in substations using the IEC 60870-5-104 protocol
Field | Description | OSI Layer |
---|---|---|
x104apci_apdulen | According to above there are packets with fixed length and with variable length containing ASDU. Fixed length packets contain control information and have the size of 4 Bytes. | |
x104apci_rx | Number of the last packet the sender received. | L7 |
x104apci_tx | Send Sequence number of the transmitted frame. This value gets increased by one for every frame which gets sent to a specific IP address. | |
x104asdu _typeid | Type IDs are described in Table 2. | |
x104asdu _causetx | Cause of Transmission values are described in Table 1 |