Topic: What does a node do? - page 3. (Read 2663 times)

it has some different functions I think. A node is able to verify the block validity and help people sync blockchain. It's a bitcoin client but with advanced functions

A node is just a normal bitcoin client. it does exactly the same as your local installed bitcoin client.

That sounds alright for Windows, but in order to allow connections from the outside the WiFi router would have to point to your device. E.g. you sit at McD and get free WiFi from their router. Lets assume its just a simple SoHo device for simplicity sake. That router has a public IP on one side, this is the IP your computer uses to talk to others in the bitcoin network. On the other side is has internal IP addresses one for each of the devices in the store. If you establish the connection from the inside those from the outside can just answer. Like with a phone call[1] you already have an existing connection if you called the other party. They dont need to call you back or something like that to reply. You can just speak back and forth. In order for someone to estabish a connection to your specific machine, the public IP is not enough. The router must also know if someone asks for "bitcoin core on TCP port 8333" on their public IP that its your laptop and your laptop only that will answer this. Chances are you will not be able to confirgure this on a public WiFi, but it might happen. Bitcoin core has a setting called "Map port using UPnP" (Settings -> Options -> Network) that will try to open the port on the router for you.


Even if you dont accept outbound connections you are a full node. Even if you dont have the full blockchain available (pruned) you are a full node. A full node is any device on the network that enforces the network rules. A full node verifies all data it gets, checks if its according to the rules and relays it unless its considered nonStandard or invalid.

A pruned node can not help others to sync up to the latest block though.

A full node that is not accepting outside connections can not be used by other wallets (like multibit) to gather data about the current state of the network.


[1] TCP connections are only virtual fixed connections over paket based IP and dont actually have a fixed line reserved for them as phone lines would before VoIP.

you need to change it to 8333 like it was said and allow outbounds connections, if you want to run a full node

Windows firewall says that Bitcoin core can use any port - should I change that to be port specific, or just leave it alone?

By running a full node, you are basically enforcing the network rules by making sure that blocks and transactions follow the rules that the client have set.  You will also be relaying transactions and blocks( when not running autoprune) to the peers, whether you open port 8333 or not. If you open port 8333, more users will be able to connect to you.

You will be part of the verification process. Each full node verifies the validity of the signature and the UXTO before relaying it.

I gather that once I have downloaded the blockchain, I will be running as a node every time I start Bitcoin core. So what will my computer be doing? As I will be using public WiFi until I finish my project (and maybe for some time afterwards), I won't be contributing a lot to the community, so what can my computer do?

Will it be supplying blocks to other users downloading the blockchain?
Will I be part of the transaction verification process?
What other services will I be able to contribute?