Computer Networks. Domain Name System. Jianping Pan Spring /25/17 CSC361 1
|
|
- Martin O’Neal’
- 6 years ago
- Views:
Transcription
1 Computer Networks Domain Name System Jianping Pan Spring /25/17 CSC361 1
2 Review: Web/HTTP Web URI/URL, HTML tags embedded/linked objects HTTP request and response persistence, statefulness web caching, content delivery; HTTP/2 Where is 1/25/17 CSC361 2
3 Today's topics Domain Name System (DNS) DNS basics host and domain names DNS hierarchies how to register your name-address mapping DNS resource records how to get your name-address mapping resolved DNS resolution queries 1/25/17 CSC361 3
4 Domain names You say host name: www domain name: google.com I say IPv4 address (4 bytes) Name-address mapping initially, centralized hosts.txt doesn t scale! 1/25/17 CSC361 4
5 DNS name space Hierarchical, distributed gtld: generic top-level domain cctld: country-code top-level domain ca uvic cs www 1/25/17 CSC361 5 * internationalized domain names Q:
6 Name hierarchy root:. cctld: ca. UVic: uvic.ca. cs.uvic.ca. address hierarchy: UVicNet: (*) EngrNet: ~95 moved from ~127 1/25/17 CSC361 6 * additional addresses for wireless
7 DNS: client's view Local DNS resolver: gethostbyname() /etc/host.conf order hosts,bind /etc/hosts nameserver /etc/resolv.conf nameserver Local DNS server: does the real job! DNS proxy ; more at DNS queries part 1/25/17 CSC361 7 * a host name vs the keyword
8 DNS: servers Local DNS server where s Root DNS server (.): {a..m}.root-servers.net ask ca0{1..6}.cira.ca., ns-ext.isc.org TLD DNS server (.ca.): ca0{1..6}.cira.ca ask dns{1 2}.uvic.ca., ns3.uvic.ca., ns.pinc.com Authoritative DNS server primary, secondary 1/25/17 CSC361 8 Q: why so many NS servers?
9 Root DNS servers {a..m}.root-servers.net. k.root a Verisign, Dulles, VA c Cogent, Herndon, VA (also Los Angeles) d U Maryland College Park, MD g US DoD Vienna, VA h ARL Aberdeen, MD j Verisign, ( 11 locations) k RIPE London (also Amsterdam, Frankfurt) i Autonomica, Stockholm (plus 3 other locations) e NASA Mt View, CA f Internet Software C. Palo Alto, CA (and 17 other locations) b USC-ISI Marina del Rey, CA l ICANN Los Angeles, CA m WIDE Tokyo 13 root name servers worldwide 1/25/17 CSC361 9 * d-root changed IPv4 addr in 2013 Q: one server, multiple locations?
10 root-servers with mirror/anycast 1/25/17 CSC
11 DNS resource records 1/25/17 CSC361 11
12 SOA, NS dig soa cs.uvic.ca cs.uvic.ca IN SOA active.uvic.ca. gduncan.dns.engr.uvic.ca origin = active.uvic.ca; mail addr = gduncan.dns.engr.uvic.ca; serial = ; refresh = 3600 (60 minutes); retry = 300 (5 minutes); expire = (7 days); minimum = 1800 (0.5 hour) replication consistency control dig ns cs.uvic.ca cs.uvic.ca IN NS dns1.uvic.ca. cs.uvic.ca IN NS active.uvic.ca. 1/25/17 CSC Q: TTL?
13 dig mx cs.uvic.ca cs.uvic.ca IN MX 0 mta.cs.uvic.ca. priority = 0 (highest) dig a cs.uvic.ca cs.uvic.ca IN A dig cname IN CNAME thing2.cs.uvic.ca. dig a thing2.cs.uvic.ca thing2.cs.uvic.ca IN A dig ptr in-addr.arpa in-addr.arpa IN PTR thing2.cs.uvic.ca. 1/25/17 CSC Q: why CNAME?
14 DNS queries Local DNS resolver-server #nslookup >set debug > QUESTIONS type = A, class = IN ANSWERS -> canonical name = thing2.cs.uvic.ca. -> thing2.cs.uvic.ca internet address = AUTHORITY RECORDS -> cs.uvic.ca nameserver = active.uvic.ca. -> cs.uvic.ca nameserver = dns1.uvic.ca. ADDITIONAL RECORDS -> dns1.uvic.ca internet address = > active.uvic.ca internet address = /25/17 CSC361 14
15 Recursive vs iterative root DNS server root DNS server. Q: recursive or not recursive ca. 2 3 cctld DNS server 4 5.ca. local DNS server dns.poly.edu uvic.ca. local DNS server dns.poly.edu uvic.ca. requesting host cis.poly.edu authoritative DNS server dns1.uvic.ca requesting host cis.poly.edu 1/25/17 CSC
16 DNS queries: more Local DNS server and higher hierarchy recursive vs iterative Reply cache time-to-live (TTL) Services required commonly by UDP Attacks on DNS cache poisoning 1/25/17 CSC * DNSSEC, DNSCurve, HTTPS, etc (CSC490 Summer 2014; JCURA'14)
17 DNS: reality check Design goals distributed, hierarchical, low overhead, robust Protocol mechanisms cache, weak consistency, redundancy e.g., at least two NS servers per domain in different subnets for redundancy; reality: many are on the same subnet due to poor provisioning e.g., stable name-address mapping for caching efficiency; reality: very short TTL in CDN Secure DNS 1/25/17 CSC What's the other DNS: De facto Network Search engine? SIGCOMM'04 OOS
18 for update: Akamai content delivery Akamai EdgePlatform 15,000+ servers 1,100+ networks 69 countries up to 15% web traffic! Server selection DNS-based for site or object delivery 1/25/17 CSC J. Pan, Y. Hou, and B. Li, ``An overview of DNS-based server selections in content distribution networks,'' Elsevier Journal of Computer Networks, 43(6): , 2003.
19 Site delivery 1/25/17 CSC361 19
20 AkaDNS.net 1/25/17 CSC361 20
21 DNS-based server selection Transparent to end-users Issues effectiveness (who s making the decision) overhead (low TTL) granularity (hostname vs. service name) proximity (client, local DNS, CDN server) accuracy (network positioning) Bottom-line: avoid the worst, hope for the best 1/25/17 CSC361 21
22 This lecture DNS DNS names and hierarchies DNS resource records DNS resolution queries DNS-based server selection site delivery : mechanisms, pros and cons Explore further CDN: object delivery 1/25/17 CSC361 22
CSc 450/550 Computer Networks Domain Name System
CSc 450/550 Computer Networks Domain Name System Jianping Pan Summer 2007 5/28/07 CSc 450/550 1 Review: Web/HTTP Web URI/URL, HTML tags, embedded objects HTTP request and response persistence, statefulness
More informationDomain Name Service. DNS Overview. October 2009 Computer Networking 1
Domain Name Service DNS Overview October 2009 Computer Networking 1 Why DNS? Addresses are used to locate objects (contain routing information) Names are easier to remember and use than numbers DNS provides
More informationCSE561 Naming and DNS. David Wetherall
CSE561 Naming and DNS David Wetherall djw@cs.washington.edu Naming and DNS Focus: How do we resolve names to addresses Names and addresses Application DNS as a system design Transport Network Link Physical
More informationChapter 2 Application Layer. Lecture 5 DNS. Computer Networking: A Top Down Approach. 6 th edition Jim Kurose, Keith Ross Addison-Wesley March 2012
Chapter 2 Application Layer Lecture 5 DNS Computer Networking: A Top Down Approach 6 th edition Jim Kurose, Keith Ross Addison-Wesley March 2012 Application Layer 2-1 Chapter 2: outline 2.1 principles
More informationIP ADDRESSES, NAMING, AND DNS
IP ADDRESSES, NAMING, AND DNS George Porter Apr 9, 2018 ATTRIBUTION These slides are released under an Attribution-NonCommercial-ShareAlike 3.0 Unported (CC BY-NC-SA 3.0) Creative Commons license These
More informationDNS. dr. C. P. J. Koymans. September 16, Informatics Institute University of Amsterdam. dr. C. P. J. Koymans (UvA) DNS September 16, / 46
DNS dr. C. P. J. Koymans Informatics Institute University of Amsterdam September 16, 2008 dr. C. P. J. Koymans (UvA) DNS September 16, 2008 1 / 46 DNS and BIND DNS (Domain Name System) concepts theory
More informationLecture 7: Application Layer Domain Name System
Lecture 7: Application Layer Domain Name System COMP 332, Spring 2018 Victoria Manfredi Acknowledgements: materials adapted from Computer Networking: A Top Down Approach 7 th edition: 1996-2016, J.F Kurose
More informationCSE 486/586 Distributed Systems
CSE 486/586 Distributed Systems The Domain Name System Slides by Steve Ko Computer Sciences and Engineering University at Buffalo CSE 486/586 Domain Name System (DNS) Proposed in 1983 by Paul Mockapetris
More informationLecture 05: Application Layer (Part 02) Domain Name System. Dr. Anis Koubaa
NET 331 Computer Networks Lecture 05: Application Layer (Part 02) Domain Name System Dr. Anis Koubaa Reformatted slides from textbook Computer Networking a top-down appraoch, Fifth Edition by Kurose and
More informationDomain Name System (DNS) 김현철 ( 화 ) 정보통신융합서울대학교컴퓨터공학부
Domain Name System (DNS) 김현철 2010.09.29 ( 화 ) 정보통신융합서울대학교컴퓨터공학부 Chapter 2 Application Layer A note on the use of these ppt slides: We re making these slides freely available to all (faculty, students,
More informationDNS and CDNs : Fundamentals of Computer Networks Bill Nace
DNS and CDNs 14-740: Fundamentals of Computer Networks Bill Nace Material from Computer Networking: A Top Down Approach, 6 th edition. J.F. Kurose and K.W. Ross Administrivia HW #1 is posted Mission: Learn
More informationCSEN 404 Introduction to Networks. Mervat AbuElkheir Mohamed Abdelrazik. ** Slides are attributed to J. F. Kurose
CSEN 404 Introduction to Networks Mervat AbuElkheir Mohamed Abdelrazik ** Slides are attributed to J. F. Kurose HTTP Method Types HTTP/1.0 GET POST HEAD asks server to leave requested object out of response
More informationCSEN 503 Introduction to Communication Networks
CSEN 503 Introduction to Communication Networks 1-1 Mervat AbuElkheir Hana Medhat Ayman Dayf ** Slides are attributed to J. F. Kurose Roadmap: Application layer Cookies and User-Server State Web caches
More informationCS 43: Computer Networks. 10: Naming and DNS September 24, 2018
CS 43: Computer Networks 10: Naming and DNS September 24, 2018 Last class Distributed systems architectures Client-Server Peer-to-Peer Challenges in design Partial failures Event ordering Lecture 10 -
More informationApplications & Application-Layer Protocols: (SMTP) and DNS
CS 312 Internet Concepts Applications & Application-Layer Protocols: E (SMTP) and DNS Dr. Michele Weigle Department of Computer Science Old Dominion University mweigle@cs.odu.edu http://www.cs.odu.edu/~mweigle/cs312-f11
More informationComputer Networking Introduction
Computer Networking Introduction Halgurd S. Maghdid Software Engineering Department Koya University-Koya, Kurdistan-Iraq Lecture No.5 Chapter 2: outline 2.1 principles of network applications app architectures
More informationThe Domain Name System
The Domain Name System Stefano Vissicchio UCL Computer Science COMP0023 Today 1. The Domain Name System (DNS) 2. A Brief Word on DNS Security A name indicates what we seek. An address indicates where it
More informationApplication-layer Protocols
Application-layer Protocols Kai Shen application transport data link physical Network Applications and Application-Layer Protocols application transport data link physical application transport data link
More informationDomain Name System (DNS)
Domain Name System (DNS) Smith College, CSC 249 Feb 6, 2017 1 TODAY: Domain Name System qthe directory system for the Internet v Used by other application layer protocols v via socket programming qmaps
More informationChapter 2: Application layer
Chapter 2: Application layer 2.1 Principles of network applications 2.2 Web and HTTP 2.3 FTP 2.4 Electronic Mail SMTP, POP3, IMAP 2.5 DNS 2.6 P2P applications 2.7 Socket programming with TCP 2.8 Socket
More informationTable of Contents DNS. Short history of DNS (1) DNS and BIND. Specification and implementation. A short history of DNS.
Table of Contents Specification and implementation DNS dr. C. P. J. Koymans Informatics Institute University of Amsterdam September 14, 2009 A short history of DNS Root servers Basic concepts Delegation
More informationELEC / COMP 177 Fall Some slides from Kurose and Ross, Computer Networking, 5 th Edition
ELEC / COMP 177 Fall 2013 Some slides from Kurose and Ross, Computer Networking, 5 th Edition Project 1 Python HTTP Server Work day: Next Tuesday (Sept 24 th ) Due Thursday, September 26 th by 11:55pm
More informationChapter 2 part B: outline
Chapter 2 part B: outline 2.3 FTP 2.4 electronic, POP3, IMAP 2.5 DNS Application Layer 2-1 FTP: the file transfer protocol at host FTP interface FTP client local file system file transfer FTP remote file
More informationCS 3516: Advanced Computer Networks
Welcome to CS 3516: Adanced Computer Networks Prof. Yanhua Li Time: 9:00am 9:50am M, T, R, and F Location: Fuller 320 Fall 2017 A-term 1 Some slides are originally from the course materials of the textbook
More informationTable of Contents DNS. Short history of DNS (1) DNS and BIND. Specification and implementation. A short history of DNS. Root servers.
Table of Contents Specification and implementation DNS Karst Koymans Informatics Institute University of Amsterdam (version 1.11, 2010/10/04 10:03:37) Tuesday, September 14, 2010 A short history of DNS
More informationCSCI-1680 DNS Rodrigo Fonseca
CSCI-1680 DNS Rodrigo Fonseca Based partly on lecture notes by Sco2 Shenker and John Janno6 Host names and IP Addresses Host names Mnemonics appreciated by humans Variable length, ASCII characters Provide
More informationEE 122: Domain Name System
EE 122: Domain Name System Ion Stoica (and Brighten Godfrey) TAs: Lucian Popa, David Zats and Ganesh Ananthanarayanan http://inst.eecs.berkeley.edu/~ee122/ Materials with thanks to Vern Paxson, Jennifer
More informationApplication Layer: , DNS
Application Layer: E-mail, DNS EECS 3214 Slides courtesy of J.F Kurose and K.W. Ross, All Rights Reserved 22-Jan-18 1-1 Chapter 2: outline 2.1 principles of network applications 2.2 Web and HTTP 2.3 electronic
More informationReminders. EE 122: Domain Name System. Goals of Today!s Lecture. Host Names vs. IP addresses. Separating Naming and Addressing
Reminders EE 122: Domain Name System Homework 2 due Oct 1 @ 3:50 pm Oct 1 is this Wednesday Project 1 checkpoint due Oct 6 @ 11:59:59 pm Ion Stoica (and Brighten Godfrey) TAs: Lucian Popa, David Zats and
More informationDNS. Karst Koymans & Niels Sijm. Tuesday, September 7, Informatics Institute University of Amsterdam
DNS Karst Koymans & Niels Sijm Informatics Institute University of Amsterdam Tuesday, September 7, 2012 Karst Koymans & Niels Sijm (UvA) DNS Tuesday, September 7, 2012 1 / 62 1 DNS: what does it do and
More informationCSE 124: IP ADDRESSES, NAMING, AND DNS. George Porter Oct 4, 2017
CSE 124: IP ADDRESSES, NAMING, AND DNS George Porter Oct 4, 2017 ATTRIBUTION These slides are released under an Attribution-NonCommercial-ShareAlike 3.0 Unported (CC BY-NC-SA 3.0) Creative Commons license
More informationCSCE 463/612 Networks and Distributed Processing Spring 2018
CSCE 463/612 Networks and Distributed Processing Spring 2018 Application Layer III Dmitri Loguinov Texas A&M University February 8, 2018 Original slides copyright 1996-2004 J.F Kurose and K.W. Ross 1 Chapter
More informationCSC 401 Data and Computer Communications Networks
CSC 401 Data and Computer Communications Networks Application Layer DNS and P2P Sec 2.4 2.5 Prof. Lina Battestilli Fall 2017 Outline Application Layer (ch 2) 2.1 principles of network applications 2.2
More informationApplication Layer. Goals: Service models. Conceptual aspects of network application protocols Client server paradigm
Application Layer Goals: Conceptual aspects of network application protocols Client server paradigm Service models Review protocols by examining popular application-level protocols HTTP DNS 1 Applications
More informationPage 1. TCP Flow Control" TCP Flow Control" TCP Flow Control" CS162 Operating Systems and Systems Programming Lecture 16. Flow Control, DNS"
CS162 Operating Systems and Systems Programming Lecture 16 Flow Control, DNS" March 28, 2011! Ion Stoica! http://inst.eecs.berkeley.edu/~cs162! TCP: stream oriented protocol! Sender sends a stream of bytes,
More informationApplication Layer. Pure P2P architecture. Client-server architecture. Processes communicating. Hybrid of client-server and P2P. Creating a network app
Application Layer e- web instant messaging remote login P2P file sharing multi- network games streaming stored video (YouTube) voice over IP real-time video conferencing cloud computing Creating a network
More informationInternet applications. 2: Application Layer 1
Internet applications 2: Application Layer 1 Recall Internet architecture Intelligence at end systems e.g., web server software communicates with browser software No need to write software for network-core
More informationTranslating Addresses
Translating Addresses Reading: Sections 9.3.1, 3.2.6. 3.2.7 Slides by Rexford @ Princeton, slightly altered by M.D. Context Application DNS DHCP Transport TCP UDP Network ICMP IP ARP Physical Physical
More informationThe basics. Karst Koymans. Tuesday, September 9, 2014
.. DNS The basics Karst Koymans Informatics Institute University of Amsterdam (version 4.7, 2014/09/11 13:54:31) Tuesday, September 9, 2014 Karst Koymans (UvA) DNS Tuesday, September 9, 2014 1 / 64 .1
More informationCompSci 356: Computer Network Architectures. Lecture 20: Domain Name System (DNS) and Content distribution networks Chapter 9.3.1
CompSci 356: Computer Network Architectures Lecture 20: Domain Name System (DNS) and Content distribution networks Chapter 9.3.1 Xiaowei Yang xwy@cs.duke.edu Overview Domain Name System Content Distribution
More informationApplication Layer. Pure P2P architecture. Client-server architecture. Processes communicating. Hybrid of client-server and P2P. Creating a network app
Application Layer e- web instant messaging remote login PP file sharing multi- network games streaming stored video (YouTube) voice over IP real-time video conferencing cloud computing Creating a network
More informationAnnouncements. Transport Protocols & DNS. Goals for Today s Lecture, Part 1. Goals of Today s Lecture, Part 2. Transport Protocols
Announcements Transport Protocols & DNS EE 122: Intro to Communication Networks Fall 2006 (MW 4-5:30 in Donner 155) We re soliciting feedback What s not working? What s working well? Send via email or
More informationf.root-servers.net ISOC cctld Workshop Nairobi, Kenya, 2005
f.root-servers.net ISOC cctld Workshop Nairobi, Kenya, 2005 The Basics DNS The Domain Name System is a huge database of resource records globally distributed, loosely coherent, scaleable, reliable, dynamic
More informationCSCI-1680 DNS Rodrigo Fonseca
CSCI-1680 DNS Rodrigo Fonseca Based partly on lecture notes by Scott Shenker and John Jannotti We know how to open TCP connections to a server/port: E.g., 128.148.32.110, port 80 Host names and IP Addresses
More informationDNS Hierarchical Name Space. BIND Terminology and DNS Name Servers. Distributed Hierarchical Database (1st Approx) Domain Name System (DNS)
Domain Name System (DNS) DNS consists of 1. an hierarchical name space name allocation decentralized to domains host.sub-subdomain.....subdomain.domain[.root] host machine name, can be an alias sub-subdomain
More informationThe Domain Name System (DNS) and its security. CSU CS557, Spring 2018 Instructor: Lorenzo De Carli Partly based on the CS457 slides by Indrajit Ray
The Domain Name System (DNS) and its security CSU CS557, Spring 2018 Instructor: Lorenzo De Carli Partly based on the CS457 slides by Indrajit Ray 1 What is the domain name system? Internet use 4- (or
More informationChapter 2 Application Layer
Chapter 2 Application Layer A note on the use of these ppt slides: We re making these slides freely available to all (faculty, students, readers). They re in PowerPoint form so you can add, modify, and
More informationCSCD 330 Network Programming Winter 2015
CSCD 330 Network Programming Winter 2015 Lecture 5 Application Layer Reading: Chapter 2 Still Some Material in these slides from J.F Kurose and K.W. Ross All material copyright 1996-2007 1 More Network
More informationLight at the end of the tunnel Final Lecture: Course Overview
Light at the end of the tunnel Final Lecture: Course Overview Acknowledgments: Lecture slides are from Computer networks course thought by Jennifer Rexford at Princeton University. When slides are obtained
More informationApplication Layer. Goals:
Application Layer Goals: Conceptual aspects of network application protocols Client server paradigm Service models Learn about protocols by examining popular applicationlevel protocols HTTP DNS SMTP, POP3,
More informationApplication Layer. Applications and application-layer protocols. Goals:
Application Layer Goals: Conceptual aspects of network application protocols Client server paradigm Service models Learn about protocols by examining popular applicationlevel protocols HTTP DNS SMTP, POP3,
More informationECE 650 Systems Programming & Engineering. Spring 2018
ECE 650 Systems Programming & Engineering Spring 2018 Dynamic Host Configuration Protocol (DHCP) and Domain Name System (DNS) Tyler Bletsch Duke University Slides are adapted from Brian Rogers (Duke) Dynamic
More informationTable of Contents DNS. Specification versus implementations. Primary use case. DNS: basic ideas and functionality. The basics. A short history of DNS
Table of Contents DNS The basics Karst Koymans DNS: basic ideas and functionality A short history of DNS Basic concepts Informatics Institute University of Amsterdam (version 17.2, 2017/09/25 12:41:49)
More informationTable of Contents DNS. Short history of DNS (1) DNS and BIND. Specification and implementation. A short history of DNS. Root servers.
Table of Contents Specification and implementation DNS Karst Koymans Informatics Institute University of Amsterdam (version 1.20, 2011/09/26 13:56:09) Tuesday, September 13, 2011 A short history of DNS
More informationNAMING, DNS, AND CHORD
NAMING, DNS, AND CHORD George Porter Oct 30 and Nov 1, 2018 ATTRIBUTION These slides are released under an Attribution-NonCommercial-ShareAlike 3.0 Unported (CC BY-NC-SA 3.0) Creative Commons license These
More informationChapter II: Application Layer
Chapter II: Application Layer UG3 Computer Communications & Networks (COMN) MAHESH MARINA mahesh@ed.ac.uk Slides thanks to Myungjin Lee, and copyright of Kurose and Ross First, a review Web and HTTP web
More informationSection 2: Application layer
Section 2: Application layer 2.1 Principles of network applications 2.2 Web and HTTP 2.3 FTP 2.4 Electronic Mail SMTP, POP3, IMAP 2.5 DNS 2.6 P2P applications 2.7 Socket programming with UDP 2.8 Socket
More informationApplication layer. Some network apps. Client-server architecture. Hybrid of client-server and P2P. Pure P2P architecture. Creating a network app
Application layer Some network apps e- web instant messaging remote login P2P file sharing multi- network games streaming stored video (YouTube) voice over IP real-time video conferencing cloud computing
More information2.5 DNS The Internet s Directory Service
130 CHAPTER 2 APPLICATION LAYER e-mail is also provided by Google, Yahoo!, as well as just about every major university and corporation. With this service, the user agent is an ordinary Web browser, and
More informationCSCD 330 Network Programming Spring 2018 Lecture 5 Application Layer. Reading: Chapter 2 Still
CSCD 330 Network Programming Spring 2018 Lecture 5 Application Layer Reading: Chapter 2 Still Some Material in these slides from J.F Kurose and K.W. Ross All material copyright 1996-2007 1 More Network
More informationDNS and HTTP. A High-Level Overview of how the Internet works
DNS and HTTP A High-Level Overview of how the Internet works Adam Portier Fall 2017 How do I Google? Smaller problems you need to solve 1. Where is Google? 2. How do I access the Google webpage? 3. How
More informationAnnouncements! Midterm Review! General Guidelines! My General Philosophy on Tests! Outline of Review! Things You Don t Need to Know!
Announcements! Extended office hours after class As long as line lasts!. Midterm Review! EE 122 Intro to Communication Networks Fall 2010 (MW 4-530 in 101 Barker) Scott Shenker TAs Sameer Agarwal, Sara
More informationlogical link name logical link name name logical link address physical address path
http://mosaic.cnfolio.com/b101cw2011article581 RelaDonship Between Layers logical link name Discovery Mike Freedman COS 461: Computer Networks h?p://www.cs.princeton.edu/courses/archive/spr14/cos461/ 2
More informationDNS. Introduction To. everything you never wanted to know about IP directory services
Introduction To DNS everything you never wanted to know about IP directory services Linux Users Victoria, April 3 rd 2007 what is the domain name system anyway? it's like a phone book...kinda DNS is (1)
More informationCMPE 150/L : Introduction to Computer Networks. Chen Qian Computer Engineering UCSC Baskin Engineering Lecture 5
CMPE 150/L : Introduction to Computer Networks Chen Qian Computer Engineering UCSC Baskin Engineering Lecture 5 1 Any problem of your lab? Due by next Monday (Jan 29) Using Canvas? Email me cqian12@ucsc.edu
More informationCSE 265: System & Network Administration
CSE 265: System & Network Administration DNS The Domain Name System History of DNS What does DNS do? The DNS namespace BIND software How DNS works DNS database Testing and debugging (tools) DNS History
More informationECE 435 Network Engineering Lecture 7
ECE 435 Network Engineering Lecture 7 Vince Weaver http://web.eece.maine.edu/~vweaver vincent.weaver@maine.edu 25 September 2018 HW#3 was Posted Announcements 1 HW#2 Review C code will be discussed next
More informationDiscovery. RelaKonship Between Layers. Discovery: Mapping Name to Address. RouKng: Mapping Link to Path. What s in a Name? Naming
RelaKonship Between Layers Discovery Mike Freedman COS 461: Computer Networks Lectures: MW 10-10:50am in Architecture N101 logical link name hep://www.cs.princeton.edu/courses/archive/spr13/cos461/ 2 Discovery:
More informationELEC / COMP 177 Fall Some slides from Kurose and Ross, Computer Networking, 5 th Edition
ELEC / COMP 177 Fall 2012 Some slides from Kurose and Ross, Computer Networking, 5 th Edition Midterm Exam Tuesday, October 16 th Format Short answer problems No questions on programming Closed notes Closed
More informationDNS. A Massively Distributed Database. Justin Scott December 12, 2018
DNS A Massively Distributed Database Justin Scott December 12, 2018 What is DNS? Translates Hostnames to IP Addresses What is DNS? Example: www.serverlogic.com 23.185.0.4 What is DNS? Example: www.serverlogic.com
More informationCMPE 150/L : Introduction to Computer Networks. Chen Qian Computer Engineering UCSC Baskin Engineering Lecture 6
CMPE 150/L : Introduction to Computer Networks Chen Qian Computer Engineering UCSC Baskin Engineering Lecture 6 1 Midterm room for overflow students The students who used my registration code to enroll
More informationK-Root Nameserver Operations
K-Root Nameserver Operations Andrei Robachevsky Chief Technical Officer andrei@ripe.net 1 Outline Root Server System What is a root server? Where is the root? Anycast Routing The basics Advantages of using
More informationApplications Layer Protocols. Hui Chen, Ph.D. Dept. of Engineering & Computer Science Virginia State University Petersburg, VA 23806
Applications Layer Protocols Hui Chen, Ph.D. Dept. of Engineering & Computer Science Virginia State University Petersburg, VA 23806 1 Acknowledgements Some pictures used in this presentation were obtained
More informationNetworking Applications
Networking Dr. Ayman A. Abdel-Hamid College of Computing and Information Technology Arab Academy for Science & Technology and Maritime Transport 1 Outline Introduction Name Space concepts Domain Name Space
More informationProject 3a is out! Goal: implement a basic network firewall. Due: Nov noon. l We give you the VM & framework. l You implement the firewall logic.
Project 3a is out! Goal: implement a basic network firewall l We give you the VM & framework. l You implement the firewall logic. Due: Nov 17 @ noon 1 What Is Firewall? Blocks malicious traffic Blocks
More informationChapter 2 Application Layer
Chapter 2 Application Layer A note on the use of these ppt slides: We re making these slides freely available to all (faculty, students, readers). They re in PowerPoint form so you see the animations;
More informationTable of Contents DNS. Primary use case. Specification versus implementations. DNS: basic ideas and functionality. The basics. A short history of DNS
Table of Contents DNS The basics Karst Koymans DNS: basic ideas and functionality A short history of DNS Basic concepts Informatics Institute University of Amsterdam (version 18.7, 2018/09/24 13:14:01)
More informationCSCD 330 Network Programming Spring 2017
CSCD 330 Network Programming Spring 2017 Lecture 5 Application Layer Reading: Chapter 2 Still Some Material in these slides from J.F Kurose and K.W. Ross All material copyright 1996-2007 1 More Network
More informationK-Root Name Server Operations
K-Root Name Server Operations Andrei Robachevsky andrei@ripe.net 1 Outline Root Server System brief update Architecture Current locations Anycast deployment K.root-servers.net Server Major milestones Current
More informationDomain Name System (DNS) DNS Fundamentals. Computers use IP addresses. Why do we need names? hosts.txt does not scale. The old solution: HOSTS.
Domain Name System (DNS) Computers use IP addresses. Why do we need names? Names are easier for people to remember DNS Fundamentals Computers may be moved between networks, in which case their IP address
More informationThe Application Layer: Sockets, DNS
The Application Layer: Sockets, DNS CS 352, Lecture 3 http://www.cs.rutgers.edu/~sn624/352-s19 Srinivas Narayana 1 App-layer protocol Types of messages exchanged, e.g., request, response Message format:
More informationDNS Basics BUPT/QMUL
DNS Basics BUPT/QMUL 2018-04-16 Related Information Basic function of DNS Host entry structure in Unix Two system calls for DNS database retrieving gethostbyname () gethostbyaddr () 2 Agenda Brief introduction
More informationELEC / COMP 177 Fall Some slides from Kurose and Ross, Computer Networking, 5 th Edition
ELEC / COMP 177 Fall 2011 Some slides from Kurose and Ross, Computer Networking, 5 th Edition Homework #1 Due Thursday Submit PDF file online via Sakai Questions? Office Hours Tue 1:30-3pm, Wed 1:30-3pm
More informationAdvanced Networking. Domain Name System
Advanced Networking Domain Name System Purpose of DNS servers Human being has many identifications: 1) Our name can be used for identification Problem: Two differenet people may have same name. 2) Mobile
More informationAdvanced Networking. Domain Name System. Purpose of DNS servers. Purpose of DNS servers. Purpose of DNS servers
Purpose of DNS servers Advanced Networking Domain Name System Human being has many identifications: 1) Our name can be used for identification Problem: Two differenet people may have same name. 2) Mobile
More informationDNS Fundamentals. Steve Conte ICANN60 October 2017
DNS Fundamentals Steve Conte ICANN60 October 2017 Names and Numbers IP addresses easy for machines but hard for people IPv4: 192.0.2.7 IPv6: 2001:db8::7 People need to use names In the early days of the
More informationSOFTWARE ARCHITECTURE 9. NAME RESOLUTION.
1 SOFTWARE ARCHITECTURE 9. NAME RESOLUTION Tatsuya Hagino hagino@sfc.keio.ac.jp lecture URL https://vu5.sfc.keio.ac.jp/slide/ 2 OSI Reference Model Open Systems Interconnect ISO defined around 1984. Application
More informationCommunications Software. CSE 123b. CSE 123b. Spring Lecture 11: Domain Name System (DNS) Stefan Savage. Some pictures courtesy David Wetherall
CSE 123b CSE 123b Communications Software Spring 2003 Lecture 11: Domain Name System (DNS) Stefan Savage Some pictures courtesy David Wetherall & Srini Seshan Where we ve been & where we re going Low-level
More informationCSE 123b Communications Software. Overview for today. Names and Addresses. Goals for a naming system. Internet Hostnames
CSE 123b Communications Software Spring 2003 Lecture 11: Domain Name System (DNS) Stefan Savage Where we ve been & where we re going Low-level networking (so far) Internetworking architecture Packet Forwarding
More informationS Computer Networks - Spring What and why? Structure of DNS Management of Domain Names Name Service in Practice
Outline What and why? Structure of DNS Management of Domain Names Name Service in Practice 188lecture12.ppt Pirkko Kuusela, Markus Peuhkuri, Jouni Karvo 1 2 Need Network addresses are numbers Addresses
More informationDNS & Iodine. Christian Grothoff.
DNS & Iodine christian@grothoff.org http://grothoff.org/christian/ The Domain Name System is the Achilles heel of the Web. Tim Berners-Lee 1 DNS: Domain Name System Unique Distributed Database Application-layer
More informationChapter 2 outline. 2.1 Principles of app layer protocols
Chapter 2 outline 2.1 Principles of app layer protocols clients and servers app requirements 2.2 Web and HTTP 2.3 FTP 2.4 Electronic Mail SMTP, POP3, IMAP 2.5 DNS 2.6 Socket programming with TCP 2.7 Socket
More informationEECS 122: Introduction to Computer Networks DNS and WWW. Internet Names & Addresses
EECS 122: Introduction to Computer Networks DNS and WWW Computer Science Division Department of Electrical Engineering and Computer Sciences University of California, Berkeley Berkeley, CA 94720-1776 Internet
More informationIntroduction to Computer Networking. Guy Leduc. Chapter 2 Application Layer. Chapter 2: outline
Introduction to Computer Networking Guy Leduc Chapter 2 Application Layer Computer Networking: A Top Down Approach, 6 th edition. Jim Kurose, Keith Ross Addison-Wesley, March 2012 2: Application Layer
More informationProtocol Classification
DNS and DHCP TCP/IP Suite Suite of protocols (not just TCP and IP) Main protocols TCP and UDP at the Transport Layer, and IP at the Network Layer Other protocols ICMP, ARP, Telnet, Ftp, HTTP, SMTP, SNMP
More informationDomain Name System.
Domain Name System http://xkcd.com/302/ CSCI 466: Networks Keith Vertanen Fall 2011 Overview Final project + presentation Some TCP and UDP experiments Domain Name System (DNS) Hierarchical name space Maps
More informationDNS. David Malone. 19th October 2004
DNS David Malone 19th October 2004 1 Names vs. Addresses Computers like addresses eg. 134.226.81.11. People prefer names salmon.maths.tcd.ie. Need a way to translate. walton.maths.tcd.ie close to salmon.maths.tcd.ie.
More informationDomain Name System - Advanced Computer Networks
- Advanced Computer Networks Saurabh Barjatiya International Institute Of Information Technology, Hyderabad 26 August, 2011 Contents 1 Distributed database, highly volatile Domain names Top level domains
More informationCS 3640: Introduction to Networks and Their Applications
CS 3640: Introduction to Networks and Their Applications Fall 2018, Lecture 19: Application Layer III (Credit: Prof. Phillipa Gill @ University of Massachusetts) Instructor: Rishab Nithyanand Teaching
More informationDomain Name System (DNS) Session-1: Fundamentals. Joe Abley AfNOG Workshop, AIS 2017, Nairobi
Domain Name System (DNS) Session-1: Fundamentals Joe Abley AfNOG Workshop, AIS 2017, Nairobi Computers use IP addresses. Why do we need names? Names are easier for people to remember Computers may be moved
More information