+Consider what happens when we are the closest node.
+
+In some of the actions it is unclear what happens when we are one of the
+closest nodes to the target key. Do we store values that we publish
+ourself?
+
+
+Add all cache files to the database.
+
+All files in the cache should be added to the database, so that they can
+be checked to make sure nothing has happened to them. The database would
+then need a flag to indicate files that are hashed and available, but
+that shouldn't be added to the DHT.
+
+
Packages.diff files need to be considered.
The Packages.diff/Index files contain hashes of Packages.diff/rred.gz
providing a later piece. This doesn't work if the differing piece is the
first piece, in which case it is downloaded from a 3rd peer, with
consensus revealing the misbehaving peer.
-
-
-Store and share torrent-like strings for large files.
-
-In addition to storing the file download location (which would still be
-used for small files), a bencoded dictionary containing the peer's
-hashes of the individual pieces could be stored for the larger files
-(20% of all the files are larger than 512 KB). This dictionary would
-have the normal piece size, the hash length, and a string containing the
-piece hashes of length <hash length>*<#pieces>. These piece hashes could
-be compared ahead of time to determine which peers have the same piece
-hashes (they all should), and then used during the download to verify
-the downloaded pieces.
-
-For very large files (5 or more pieces), the torrent strings are too
-long to store in the DHT and retrieve (a single UDP packet should be
-less than 1472 bytes to avoid fragmentation). Instead, the peers should
-store the torrent-like string for large files separately, and only
-contain a reference to it in their stored value for the hash of the
-file. The reference would be a hash of the bencoded dictionary. If the
-torrent-like string is short enough to store in the DHT (i.e. less than
-1472 bytes, or about 70 pieces for the SHA1 hash), then a
-lookup of that hash in the DHT would give the torrent-like string.
-Otherwise, a request to the peer for the hash (just like files are
-downloaded), should return the bencoded torrent-like string.
-
-
-PeerManager needs to track peers' properties.
-
-The PeerManager needs to keep track of the observed properties of seen
-peers, to help determine a selection criteria for choosing peers to
-download from. Each property will give a value from 0 to 1. The relevant
-properties are:
-
- - hash errors in last day (1 = 0, 0 = 3+)
- - recent download speed (1 = fastest, 0 = 0)
- - lag time from request to download (1 = 0, 0 = 15s+)
- - number of pending requests (1 = 0, 0 = max (10))
- - whether a connection is open (1 = yes, 0.9 = no)
-
-These should be combined (multiplied) to provide a sort order for peers
-available to download from, which can then be used to assign new
-downloads to peers. Pieces should be downloaded from the best peers
-first (i.e. piece 0 from the absolute best peer).
-
-
-Missing Kademlia implementation details are needed.
-
-The current implementation is missing some important features, mostly
-focussed on storing values:
- - values need to be republished (every hour?)
- - original publishers need to republish values (every 24 hours)
- - when a new node is found that is closer to some values, replicate the
- values there without deleting them
- - when a value lookup succeeds, store the value in the closest node
- found that didn't have it
- - make the expiration time of a value exponentially inversely
- proportional to the number of nodes between the current node and the
- node closest to the value
projects / quix0rs-apt-p2p.git / blobdiff