-Files for which a hash cannot be found should not be added to the DHT.
+Evaluate and fix some errors in the ktable khashmir module.
-If the hash can't found, it stands to reason that other peers will not
-be able to find the hash either. So adding those files to the DHT will
-just clutter it with useless information. Examples include Release.gpg,
-Release, Translation-de.bz2, and Contents.gz.
+The KTable implementation has some possible errors in it. insertNode
+does not remove the original and use the new node when updating a node
+already in the table, as claimed by the comments. justSeenNode doesn't
+verify that the found node is the node that was being looked for, nor
+does it move the node to the end of the list of nodes (since they are
+supposed to be sorted by their lastSeen time) or update the bucket's
+last touched time.nodeFailed also doesn't verify the found node is the
+right node.
-Use python-debian for parsing RFC 822 files.
+Consider what happens when we are the closest node.
-There are already routines for parsing these files, so there is no need
-to write more. In the AptPackages, change the Release file parsing to
-use the python-debian routines.
+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.
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
+Consider adding peer characteristics to the DHT.
+
+Bad peers could be indicated in the DHT by adding a new value that is
+the NOT of their ID (so they are guaranteed not to store it) indicating
+information about the peer. This could be bad votes on the peer, as
+otherwise a peer could add good info about itself.
+
+
+Consider adding pieces to the DHT instead of files.
+
+Instead of adding file hashes to the DHT, only piece hashes could be
+added. This would allow a peer to upload to other peers while it is
+still downloading the rest of the file. It is not clear that this is
+needed, since peer's will not be uploading and downloading ery much of
+the time.
projects / quix0rs-apt-p2p.git / blobdiff