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Name Services. From Chapter 9 of Distributed Systems Concepts and Design,4 th Edition, By G. Coulouris, J. Dollimore and T. Kindberg Published by Addison Wesley/Pearson Education June 2005. Topics.
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Name Services From Chapter 9 of Distributed Systems Concepts and Design,4th Edition, By G. Coulouris, J. Dollimore and T. Kindberg Published by Addison Wesley/Pearson Education June 2005
Topics Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Introduction Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Introduction Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Introduction Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Introduction Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
URL http://www.cdk3.net:8888/WebExamples/earth.html DNS lookup Resource ID (IP number, port number, pathname) 138.37.88.61 8888 WebExamples/earth.html ARP lookup (Ethernet) Network address file 2:60:8c:2:b0:5a Socket Web server Introduction Figure 1. Composed naming domains used to access a resource from a URL Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Name Services and the Domain Name System Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Name Services and the Domain Name System Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
NS2 2 Name 1 NS1 servers Client 3 NS3 A client iteratively contacts name servers NS1–NS3 in order to resolve a name Name Services and the Domain Name System Figure 2. Iterative navigation Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Name Services and the Domain Name System Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Name Services and the Domain Name System Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
NS2 NS2 2 2 4 3 1 1 NS1 NS1 client client 3 5 4 NS3 NS3 Recursive Non-recursive server-controlled server-controlled Name Services and the Domain Name System Figure 3. Non-recursive and recursive server-controlled navigation Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Name Services and the Domain Name System Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
a.root-servers.net (root) au purdue.edu ns1.nic.au yahoo.com .... (au) ns.purdue.edu (purdue.edu) com.au edu.au... ns0.ja.net (edu.au) * .purdue.edu usyd.edu.au unimelb.edu.au... abc.unimelb.edu.au mulga.csse.unimelb.edu.au dns0-doc.usyd.edu.au (unimelb.edu.au) (csse.unimelb.edu.au) (usyd.edu.au) csse.unimelb.edu.au *.csse.unimelb.edu.au *.usyd.edu.au *.unimelb.edu.au Name Services and the Domain Name System Note: Name server names are in italics, and the corresponding domains are in parentheses.Arrows denote name server entries authoritative path to lookup: raj-pc.csse.unimelb.edu.au Figure 4. DNS name servers Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Name Services and the Domain Name System Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005
Name Services and the Domain Name System Record type Meaning Main contents A A computer address IP number NS An authoritative name server Domain name for server CNAME The canonical name for an alias Domain name for alias SOA Marks the start of data for a zone Parameters governing the zone WKS A well-known service description List of service names and protocols PTR Domain name pointer (reverse Domain name lookups) HINFO Host information Machine architecture and operating system MX Mail exchange List of < TXT Text string Arbitrary text Figure 5. DNS resource records Couloris,Dollimore and Kindberg Distributed Systems: Concepts & Design Edn. 4 , Pearson Education 2005