Request: Ping ("ping")
Connection keep-alive, "aliveness" and latency discovery.
If a node receives a ping message, it replies as quickly as possible with a pong message with the provided nonce.
Message Format
| Field | Length | Format | Description | 
|---|---|---|---|
| nonce | 8 bytes | unsigned 64 bit integer(LE) | An arbitrary value provided to connect the ping message with the pongreply. |