Peer connection type modes
A Freenet 0.7 node will allow you to set each peer to one of several connection modes. The option to do so is available via FCP, and if Advanced mode is enabled, via the web interface Darknet page. The modes control whether we will connect to a node, and how hard we will try to do so. These are the modes:
Normal - Send handshakes every 20-30 seconds while the peer is disconnected, attempting to connect.
Disabled - Don't send handshakes to the peer, and don't connect to it if we receive one; never connect to the peer until it is re-enabled.
Listen
Only - Listen for handshake packets from the peer, but never send them.
Burst
Only - Listen for handshake packets from the peer, but only send handshakes occasionally.
A handshake packet is a few hundred bytes long. In normal mode we send these frequently, because some NATs have tunnel lifetimes of 30 seconds. Generally speaking you should use normal mode. Here's why. Below we have a table of outcomes with two nodes (A and B) trying to connect to each other, with different connection modes. "Open" means that the node either isn't behind a NAT or is behind a full cone NAT, which is effectively the same thing most of the time. (Most consumer NATs are port-restricted or worse). Note that the below doesn't incorporate
ARKs; it will often be possible for the node to discover the new IP of the other node through ARKs, but only if it has other connections which work.
| A mode | B mode | Result |
|---|
| A normal | B normal | If neither node is open, works unless A's or B's IP changes.
If A or B is open, works unless both A and B change IP. |
| A normal | B listen-only | Works (immediately) if B is open, unless B's IP changes (A's can change). |
| A normal | B burst-only | Works (immediately) if B is open, unless B's IP changes (A's can change).
Works (when B bursts) if A is open, unless A's IP changes (B's can change). |
| A burst-only | B burst-only | Does not work at all if neither node is open, because the bursts will not usually coincide.
Works if B is open, unless B's IP changes (A's IP can change).
Works if A is open, unless A's IP changes (B's IP can change). |
| A burst-only | B listen-only | Works (when A bursts) if B is open, unless B's IP changes. |
| A listen-only | B listen-only | Never works! |
Bottom line: Use normal mode, unless you are sure you are not behind a NAT, and your IP never changes.