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Packet capture of device gateway_
| Date | Time | Direction | ID | Address | Port | Hex Dump |
|---|---|---|---|---|---|---|
| 5/14/2021 | 10:04:51 AM | IN | 2 | 41.13.196.229 | 45708 | 08780200000081ff |
| 5/14/2021 | 10:04:51 AM | OUT | 2 | 41.13.196.229 | 45708 | 08f80200000051dd |
| 5/14/2021 | 10:04:58 AM | IN | 7 | 41.13.204.231 | 38968 | 087807000000c443 |
| 5/14/2021 | 10:04:58 AM | OUT | 7 | 41.13.204.231 | 38968 | 08f8070000001461 |
| 5/14/2021 | 10:05:26 AM | IN | 3 | 41.13.254.98 | 47490 | 0878030000003589 |
| 5/14/2021 | 10:05:26 AM | OUT | 3 | 41.13.254.98 | 47490 | 08f803000000e5ab |
| 5/14/2021 | 10:05:43 AM | IN | 1 | 41.13.208.106 | 33612 | 0878010000005d64 |
| 5/14/2021 | 10:05:43 AM | OUT | 1 | 41.13.208.106 | 33612 | 08f8010000008d46 |
| 5/14/2021 | 10:05:53 AM | IN | 2 | 41.13.196.229 | 46236 | 08780200000081ff |
| 5/14/2021 | 10:05:53 | OUT | 2 | 41.13.196.229 | 46236 | 08f80200000051dd |
Gateway packet format_
| CoCT Gateway Packet Format | |||||||||||||||||||
| Section | Header | ID | Date | CRC | |||||||||||||||
| Size in Bytes | 2 | 4 | X | 2 | |||||||||||||||
| Bits | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 0 – 31 | 0 – 15 | |
| Field | version | type | ack | length | deviceID | ||||||||||||||
Snapshot summary of comparison of protocols_
| Description | OPC UA | MQTT | COAP |
|---|---|---|---|
| Protocol binding | TCP | TCP | UDP |
| Server/ client | Pub/sub | Server/ client | |
| Security | Excellent | Good | Fair |
| Reliability over networks | Only good over very stable networks with excellent bandwidths | Suitable for transferring data/commands over unstable connections | Ideal for client/server connections |
| Architecture | Client-server model | Broker is the centre of the network | Node is the centre of the network |
| Controllability of nodes | Offers secure controllability. | No controllability built into the protocol | Offers controllability of nodes within the protocol |