LastSeen or Last Sent/Received

[b00f]

Currently, when we receive data from a peer, we update the LastSeen property.

In Bitcoin, they have two properties per peer: lastsend and lastrecv. Look here

Should we maintain a record of the last send/receive, or should we just keep the last seen property?

[b00f]

@amirvalhalla What is your opinion?

[kehiy]

@amirvalhalla
sure, in our case lastrecv make more sense instead of lastseen
its more clear

[b00f]

As @amirvalhalla suggested, it is better to change last seen to last received. This property enables each node to determine whether a specific peer in the network is offline. This feature specifically allows us to implement a garbage collector, which removes offline nodes from the PeerSet.

I'm wondering, is there any situation in which we might be interested in knowing the last time we sent data to a peer (or last sent)?

Let me elaborate a bit:

We have two methods to send data: Broadcast (Gossiping) and Direct Send (Streaming):

• In broadcast mode, we gossip data to all peers in the network, such as a vote message.
• In direct send mode, we stream data directly to a specific node. There is a direct channel between two peers. Right now, we have only one scenario for streaming: Block Request -> Block Response. If a node is syncing itself, it may request data from a peer and in response it gets the missed blocks.

Therefore, the last sent timestamp could may tell us when this node was last fully synced and didn't go offline and never missed any new blocks.

[amirvalhalla]

by this scenario , I Agree with lastsent property because we should know when a node send data for the last time.

[b00f]

Good news that only one place we need to change: sendTo function in sync package.
Then we can add this property to proto file and as well in HTTP

[amirvalhalla]

@b00f

okay , I'll refactor this section as soon as possible