Packet
挖得比光速還快,可能嗎?
我個人喜歡
dig
我知道的網站。.這是我執行後在終端上看到的一件奇怪的事情dig www-contestwinners.com
:-; <<>> DiG 9.9.5-3ubuntu0.1-Ubuntu <<>> www-contestwinners.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27237 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;www-contestwinners.com. IN A ;; ANSWER SECTION: www-contestwinners.com. 300 IN A 8.29.143.192 ;; Query time: 40 msec ;; SERVER: 127.0.1.1#53(127.0.1.1) ;; WHEN: Sun Jun 06 20:31:40 IST 2015 ;; MSG SIZE rcvd: 67
這是荒謬的,因為我的 ISP 離我大約 200 公里,而且我正在使用 DSL 連接。考慮到數據包以光速傳播,這使得數據包從我的設備到達 ISP 伺服器的時間約為 0.6 毫秒,這並不多,但該站點的伺服器位於美國,距離我的 ISP 13000 公里使到達伺服器的時間約為 43 毫秒。因此,總往返時間約為 (43+0.6)x2= 87.2 ms。
我完全感到困惑/興奮。我想我剛剛打破了物理學的基本定律:p
**編輯:**我檢查
dig www-contestwinners.com +trace
了記憶體並得到:-;; global options: +cmd . 412410 IN NS i.root-servers.net. . 412410 IN NS k.root-servers.net. . 412410 IN NS f.root-servers.net. . 412410 IN NS g.root-servers.net. . 412410 IN NS e.root-servers.net. . 412410 IN NS l.root-servers.net. . 412410 IN NS h.root-servers.net. . 412410 IN NS b.root-servers.net. . 412410 IN NS a.root-servers.net. . 412410 IN NS m.root-servers.net. . 412410 IN NS j.root-servers.net. . 412410 IN NS c.root-servers.net. . 412410 IN NS d.root-servers.net. . 518400 IN RRSIG NS 8 0 518400 20150618050000 20150608040000 48613 . TJF2HD0Ob5niqlCZNhlOYHvwlZmEpebgV8uFwgvRLBCQb22sq+S8Hr4d CX9S5WgzRlTxCSQ3Bi9TJNlyf221rE1K53kFbRae6/vzjR2MukvF5d8G SEWinOcJ9n7l6fTq/HoxCv/GfliY6gTPWxrc8uiABdYYOj3u3XoUmbF7 Cug= ;; Received 397 bytes from 127.0.1.1#53(127.0.1.1) in 5306 ms com. 172800 IN NS a.gtld-servers.net. com. 172800 IN NS b.gtld-servers.net. com. 172800 IN NS c.gtld-servers.net. com. 172800 IN NS d.gtld-servers.net. com. 172800 IN NS e.gtld-servers.net. com. 172800 IN NS f.gtld-servers.net. com. 172800 IN NS g.gtld-servers.net. com. 172800 IN NS h.gtld-servers.net. com. 172800 IN NS i.gtld-servers.net. com. 172800 IN NS j.gtld-servers.net. com. 172800 IN NS k.gtld-servers.net. com. 172800 IN NS l.gtld-servers.net. com. 172800 IN NS m.gtld-servers.net. com. 86400 IN DS 30909 8 2 E2D3C916F6DEEAC73294E8268FB5885044A833FC5459588F4A9184CF C41A5766 com. 86400 IN RRSIG DS 8 1 86400 20150618050000 20150608040000 48613 . kSsNvyvdzfiJAxfpaRq4+bAe2JuKcDTcRnHDgGhiHNRsbcg04fHv/TNt Kkl0LuBpLcBWhBr74OkCLJxx5Q1KFkRhum2R7gHj6h5u8s4J84feqWeu fx69Defg2NWhToWDnqz0WzlUKF0nDsEyXTJDjsUeFrXu+baR3NSMLxvb zdU= ;; Received 746 bytes from 192.203.230.10#53(e.root-servers.net) in 5221 ms www-contestwinners.com. 172800 IN NS dan.ns.cloudflare.com. www-contestwinners.com. 172800 IN NS anna.ns.cloudflare.com. CK0POJMG874LJREF7EFN8430QVIT8BSM.com. 86400 IN NSEC3 1 1 0 - CK0QFMDQRCSRU0651QLVA1JQB21IF7UR NS SOA RRSIG DNSKEY NSEC3PARAM CK0POJMG874LJREF7EFN8430QVIT8BSM.com. 86400 IN RRSIG NSEC3 8 2 86400 20150613045314 20150606034314 33878 com. syTPVIWKgitzBOsgVgzOl7nEIsu7jhsmSXPzzLuGVUwZZC1QHc4dxmKP MkZUR+VcaY657/Knjk7Il5oOKWo8ZlTatk3+34504gWwdnbB3BShqTKS CFsWOEdw5wyf0gumuQk5GKnVR5Noo+q2+ZOxxy7LkEl0F/h7fuYj7sJA VkM= A7FUA6LKSQCDHL6JDO7SFU649KJ6FAU5.com. 86400 IN NSEC3 1 1 0 - A7G276R35K72HBA9TE7NSAOEFTS5CADU NS DS RRSIG A7FUA6LKSQCDHL6JDO7SFU649KJ6FAU5.com. 86400 IN RRSIG NSEC3 8 2 86400 20150614050705 20150607035705 33878 com. lIZrvjQdR4oNJTo8gW1uuzs1IuFXiqwZbI757xxBRdrYl22IDSDM4U4G i8PNVSOQ2T3ub++0VhoioWnp3aD+Uc1XmdR/jI5Z5bosIsfIrCj+CSCm ZlDShTEDsfOBLxvZ2LByGwibTHi/yuH57O+Zx3zp21RZu3xLAn2WT2aZ TrE= ;; Received 675 bytes from 192.12.94.30#53(e.gtld-servers.net) in 1539 ms www-contestwinners.com. 300 IN A 8.29.143.192 ;; Received 67 bytes from 173.245.59.108#53(dan.ns.cloudflare.com) in 53 ms
這怎麼可能?
您查詢的域名伺服器不在美國。它離你更近了。(因此,不幸的是,您的諾貝爾獎將不得不等待。)
該跟踪輸出顯示 www-contestwinners.com 正在使用 CloudFlare 作為其 DNS 提供商。CloudFlare在世界各地運營著眾多伺服器,您的查詢被定向到最近的(或他們可以管理的最好的)伺服器。
(請注意,名稱伺服器不需要(通常也不需要)位於 Web 伺服器附近。通常名稱伺服器甚至不是由同一家公司處理。)