P2P(peer-to-peer,\u5c0d\u7b49\u5f0f\u7db2\u8def)
end-system\u53ef\u4e92\u76f8\u9023\u7dda,\u53ef\u4ee5\u4e0d\u7528\u900f\u904eserver\u4e5f\u80fd\u904b\u4f5c<\/p>\n\n\n\n
…<\/p>\n\n\n\n \u5faa\u74b0\u5f0fDHT\u641c\u5c0bkey\u8ca0\u8cac\u5c0d\u7b49\u9ede<\/strong> P2P(peer-to-peer,\u5c0d\u7b49\u5f0f\u7db2\u8def)end-sys …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"","fifu_image_alt":"","_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[29],"tags":[],"class_list":["post-845","post","type-post","status-publish","format-standard","hentry","category-osi-layer7"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts\/845","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/comments?post=845"}],"version-history":[{"count":0,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts\/845\/revisions"}],"wp:attachment":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/media?parent=845"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/categories?post=845"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/tags?post=845"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\u5e38\u898b\u7684P2P\u5354\u5b9a<\/strong>
eMule: \u6a94\u6848\u50b3\u8f38
BitTorrent: \u6a94\u6848\u50b3\u8f38
KanKan:P2P Streaming
Skype:\u7528\u5728VoIP<\/p>\n\n\n\n
……………………………….
\u4ee5\u4e0b\u4ee5Bittorrent\u70ba\u7bc4\u4f8b\u4ecb\u7d39\u5176\u539f\u4f5c\u6a5f\u5236<\/p>\n\n\n\n
Bittorrent\u53c3\u8207\u7684\u5143\u4ef6<\/strong>
Peer(\u5c0d\u7b49\u9ede)<\/strong>:\u53c3\u8207p2p\u7684\u96fb\u8166,
Neighbors peer(\u76f8\u9130\u5c0d\u7b49\u9ede)<\/strong>: \u8207\u5c0d\u7b49\u9ede\u6210\u529f\u5efa\u7acb\u9023\u7dda\u7684\u5176\u4ed6\u5c0d\u7b49\u9ede
Torrent<\/strong>:\u6240\u6709\u53c3\u8207\u6a94\u6848\u50b3\u8f38\u7684\u5c0d\u7b49\u9ede
Chunks<\/strong>: \u50b3\u8f38\u6a94\u6848\u7684\u6700\u5c0f\u57fa\u672c\u55ae\u4f4d,\u9810\u8a2d256KB
Tracker(\u8ffd\u8e64\u8005)<\/strong>: Torrent\u5167\u81f3\u5c11\u6703\u6709\u4e00\u500b\u7684\u57fa\u790e\u7bc0\u9ede, \u8b93\u525b\u52a0\u5165torrent\u7684peer\u8a3b\u518a,\u4ee5\u8ffd\u8e64\u5c0d\u7b49\u9ede\u7684\u72c0\u6cc1
Peer list<\/strong>: \u8a18\u9304\u6bcf\u500bpeer\u7684IP, \u6703\u8a18\u9304\u525b\u52a0\u5165\u7684peer\u4e00\u958b\u59cb\u8981\u806f\u7e6b\u7684IP\u6e05\u55ae<\/p>\n\n\n\n
Peer\u884c\u70ba<\/strong>
1.\u7576peer\u525b\u52a0\u5165Torrent\u6642,
\u3000\u5411tracker\u8a3b\u518a\u81ea\u5df1,
\u3000\u6b64\u6642peer\u6c92\u6709\u4efb\u4f55chunk
2.tracker\u5c07peer list\u7d66\u525b\u52a0\u5165\u7684peer
\u3000\u525b\u52a0\u5165\u7684peer\u6703\u5148\u548cpeer list\u4e2d\u7684IP\u5efa\u7acb\u9023\u7dda
3.peer\u5728\u53d6\u5f97\u6a94\u6848\u6642,
\u3000peer\u6703\u9031\u671f\u6027\u7684\u544a\u77e5tracker\u76ee\u524d\u72c0\u6cc1,
\u3000\u6703\u5f9eneighbors peer\u4e0b\u8f09\u8d8a\u4f86\u8d8a\u591achunk,\u540c\u6642\u4e5f\u6703\u4e0a\u50b3chunk\u7d66neighbors peer
\u3000peer\u53ef\u80fd\u6703\u96a8\u6642\u96e2\u958b\u6216\u52a0\u5165Torrent
4.\u4e00\u4f46peer\u53d6\u5f97\u6240\u9700\u8981\u7684\u5b8c\u6574\u6a94\u6848,
\u3000\u53ef\u80fd\u6703\u96e2\u958bTorrent,
\u3000\u6216\u662f\u5728Torrent\u4e2d\u7e7c\u7e8c\u5206\u4eabchunk\u7d66neighbors peer<\/p>\n\n\n\n
\u4e0b\u8f09\u7b56\u7565, rarest first(\u6700\u7a00\u6709\u512a\u5148)<\/strong>
peer\u6703\u6709\u6240\u6709neighbors peer\u7684chunks\u5217\u8868, \u6bcf\u500b\u5217\u8868\u90fd\u6703\u4e0d\u540c,
peer\u6703\u6839\u64da\u81ea\u5df1\u7f3a\u5c11\u7684chunk\u548c\u9019\u4e9b\u5217\u8868,\u8a08\u7b97\u51fa\u6700\u7a00\u6709\u7684chunk,\u4e26\u5411\u6709\u6b64chunk\u7684neighbors peer\u8981\u6c42\u4e0b\u8f09
\u6b64\u7b56\u7565\u53ef\u4ee5\u8b93\u6700\u7a00\u6709\u7684chunk\u9010\u6f38\u8b8a\u666e\u53ca,\u8b93\u5404peer\u6709\u6a5f\u6703\u4e0b\u8f09<\/p>\n\n\n\n
\u4e0a\u50b3\u7b56\u7565,tit-for-tat(\u4ee5\u5fb7\u5831\u5fb7\u7b56\u7565)<\/strong>
peer\u53ea\u6703\u5c07chunk\u4e0a\u50b3\u7d66unchoked\u548coptimistically unchoked\u7684neighbors peer
unchoked(\u7121\u963b\u7684)<\/strong>:peer\u6bcf10\u79d2\u6703\u8a08\u7b97\u524d4\u540d\u53ef\u6700\u5feb\u4e0b\u8f09\u7684neighbors peer
optimistically unchoked(\u6a02\u89c0\u7121\u963b\u7684)<\/strong>: peer\u6bcf30\u79d2\u6703\u96a8\u6a5f\u9078\u64c71\u540dneighbors peer
choked(\u88ab\u963b\u65b7\u7684)<\/strong>:\u9664\u4e86\u90195\u500bneighbors peer\u4ee5\u5916\u7684neighbors peer\u90fd\u662f\u88ab\u963b\u65b7\u7684
\u6b64\u7b56\u7565\u53ef\u627e\u51fa\u66f4\u597d\u7684trading partners<\/p>\n\n\n\n
DHT(distributed hash table,\u5206\u6563\u5f0f\u96dc\u6e4a\u8868)<\/strong>
Distributed P2P database, peer\u53ef\u7528\u4f86\u67e5\u8a62\u90a3\u500b\u6a94\u6848\u5728\u90a3\u500bpeer\u7684\u8cc7\u6599\u5eab
\u7531key,value\u7d44\u6210\u7684table , ex: (linux, \u5c0d\u7b49\u9edea) , (linux, \u5c0d\u7b49\u9edeb)
DHT\u6563\u5e03\u5728\u5404peer, \u6bcf\u500bpeer\u50c5\u6301\u6709\u6574\u9ad4key,value\u914d\u5c0d\u7684\u4e00\u90e8\u4efd
DHT\u904b\u4f5c\u5c6c\u65bcoverlay network,\u4e5f\u5c31\u662f\u5728\u5be6\u9ad4\u7db2\u8def\u4e4b\u4e0a\u6703\u6709\u81ea\u5df1\u7684\u908f\u8f2f\u7db2\u8def<\/p>\n\n\n\n
DHT\u89d2\u8272<\/strong>
key\u8ca0\u8cacpeer<\/strong>: \u64c1\u6709\u6b64keyValue\u914d\u5c0d\u7684peer
immediate successor peer<\/strong>: \u6700\u63a5\u8fd1\u6b64peer ID\u7684\u4e0b\u4e00\u500bpeer
immediate predecessor peer<\/strong>:\u6700\u63a5\u8fd1\u6b64peer ID\u7684\u4e0a\u4e00\u500bpeer<\/p>\n\n\n\n
peer\u641c\u5c0bkey\u8ca0\u8cacpeer\u6642, \u53ea\u6703\u554fimmediate successor peer
\u82e5immediate successor peer\u6c92\u6709,\u5c31\u6703\u5728\u554f\u4ed6\u7684immediate successor peer,\u4ee5\u6b64\u985e\u63a8
\u82e5immediate successor peer\u6709,\u5c31\u6703\u56de\u50b3\u7d66\u539f\u59cbpeer, \u81ea\u5df1\u662fkey\u8ca0\u8cacpeer
ps:
peer\u53ea\u6703\u8655\u7406immediate predecessor peer\u7684\u641c\u5c0b
ps:
\u6b64\u641c\u5c0b\u6a5f\u5236\u6700\u906d\u7684\u60c5\u6cc1\u4e0b, \u6703\u4e00\u500b\u4e00\u500b\u554fpeer\u554f\u5230\u6700\u5f8c\u624d\u627e\u5230<\/p>\n\n\n\n
\u5728DHT\u5132\u5b58keyvalue\u914d\u5c0d<\/strong>
1.\u8a08\u7b97key\u7684hash
2.\u6839\u64da\u4ee5\u4e0b\u6b65\u9a5f\u6c7a\u5b9apeer
\u627e\u51fa\u548c\u6b64hash\u4e00\u6a23\u7684peer ID
\u82e5\u7121,\u5247\u5c0b\u627e\u6700\u63a5\u8fd1\u6b64hash\u7684peer ID,\u800c\u4e14\u5fc5\u9808\u662f\u4e0b\u4e00\u500b
\u82e5\u7121,\u5247\u5c0b\u627e\u6700\u5c0f\u7684peer ID
3.\u6839\u64da\u6b64peer ID , \u5132\u5b58\u6b64keyvalue\u5230\u6b64peer
ex:
\u5047\u8a2dpeer\u67094\u500b,\u8b58\u5225\u78bc\u5206\u5225\u662f1,2,4,8
\u82e5key\u7684hash\u70ba5,\u5c31\u5c07\u6b64keyvalue\u914d\u5c0d\u63d2\u5165\u4e0b\u4e00\u500b\u6700\u63a5\u8fd1\u7684peer 8
\u82e5key\u7684hash\u70ba9,\u5c31\u5c07\u6b64keyvalue\u914d\u5c0d\u63d2\u5165\u6700\u5c0f\u7684peer 1<\/p>\n\n\n\n
peer churn:\u96e2\u958bDHT<\/strong>
peer\u6703\u5075\u6e2c\u5f8c2\u500bimmediate successor peer
\u82e5immediate successor peer\u96e2\u958b ,
\u5247\u8b93\u7b2c\u4e8c\u500bimmediate successor peer\u7576\u7b2c\u4e00\u500b<\/p>\n\n\n\n
\u641c\u5c0bDHT\u4e0b\u500b\u5c0d\u7b49\u9ede<\/strong>
\u7576peer\u52a0\u5165DHT\u6642, \u82e5\u4e0d\u77e5\u9053immediate successor peer\u548cimmediate predecessor peer
\u5c31\u6703\u5c0b\u554f\u5b58\u5728DHT\u7684\u5176\u4e2d1\u500bpeer,\u6b64peer\u6703\u4e00\u8def\u8f49\u9001\u6b64\u554f\u984c,
\u7576\u8f49\u9001\u5230\u6b63\u78ba\u7684immediate predecessor peer ,\u6b64peer\u505a2\u4ef6\u4e8b
\u30001.\u76f4\u63a5\u56de\u8986\u7d66\u525b\u52a0\u5165peer\u4ee5\u4e0b\u8cc7\u8a0a
\u3000\u3000immediate predecessor peer:\u81ea\u5df1
\u3000\u3000immediate successor peer:\u81ea\u5df1\u7684\u4e0b\u4e00\u500bpeer
\u30002.\u5c07\u539f\u672cimmediate predecessor peer\u8a2d\u6210\u525b\u52a0\u5165\u7684peer<\/p>\n","protected":false},"excerpt":{"rendered":"