Time since reference or first frame: 0.000000000 seconds Time delta from previous packet: 0.000000000 seconds $ sudo tshark -i eth0 -V -f 'ether host 01:00:0c cc:cc' -c 2įrame 1 (386 bytes on wire, 386 bytes captured) XXX - Add example traffic here (as plain text or Wireshark screenshot). PPP: CDP is encapsulated over PPP with a protocol type of 0x0207. LLC/ SNAP: CDP is encapsulated as LLC/SNAP with an OUI of 0x00000C and a protocol ID of 0x2000.Ĭisco HDLC: CDP is encapsulated over Cisco HDLC with a protocol type of 0x2000. XXX - add a brief description of CDP history (see third external link for a detailed history) Protocol dependencies The purpose of the protocol is to supply a network entity with information about its direct connected neighbors. Hence, these are gaps that we as part of the ICS community need to improve on.CDP (Cisco Discovery Protocol) is a Cisco proprietary protocol that runs between direct connected network entities (routers, switches, remote access devices, IP telephones etc.). With digitalization, ICS will become more interconnected and open with. Furthermore, although there is now Secure Modbus with encryption, it is only available for Modbus TCP, and it is not yet widely adopted, especially by legacy serial communication systems.

Similarly, if an attacker wants to spoof communication or conduct a replay attack, he can do so without authentication. In fact, machine learning and artificial intelligence can be leveraged to notify the operator if there is any unusual patterns in polling time intervals, the slave that the master is polling, the register being read or the data itself.Īnother concern about traditional ICS protocols is that all information, from the device ID, to the function code, to the payload, are all in cleartext for anyone with a parser to see. This enables them to identify anomalous behaviors or malicious packets embedded. It is important for cyber security personnel protecting OT systems to have a good understanding of ICS protocols such as Modbus. In the fourth packet, the slave replies to the master, this time the value in register 0 is 16840 (hex 41c8).

Wireshark ip id