Distribuerede Systemer 2016 - Web services and Protocols

Copenhagen Business School 2016 (HA(it.) 2. semester in Distributed Systems Class.

Transcript

1. Interoperationalitet
2. Lokal Name Server TLD Root
3. https://learn.cbs.dk:443/course/view.php?id=2#topic1 Protokol Sub domain Domain TLD Port Path Query Fragment
4. URI A Uniform Resource Identifier (URI) is a compact sequence of characters that identifies an abstract or physical resource. http://www.iana.org/assignments/uri-schemes Adresser og deres mange navne URL A URI can be further classified as a locator, a name, or both. The term “Uniform Resource Locator” (URL) refers to the subset of URIs that, in addition to identifying a resource, provide a means of locating the resource by describing its primary access mechanism (e.g., its network “location”)
5. IP Up to 64 kilobyte Source IP Destination IP Data HEADER
6. 192.168.0.4 192.168.0.3 192.168.0.5 192.168.0.6 192.168.0.2 192.168.0.1 Lokalt Net ROUTER NAT Firewall 192.168.0.0/255 192.168.0.7 Internettet Hjemmenetværk
7. 192.168.0.4 192.168.0.3 192.168.0.5 192.168.0.6 192.168.0.2 192.168.0.1 Lokalt Net ROUTER NAT Firewall 192.168.0.0/255 192.168.0.7 Internettet :80 smadreprincesser.dk:80 smadreprincesser.dk:443 :443 Portforward
8. SYN SYN - ACK ACK TCP
9. DATA UDP DATA DATA
10. “ Et distribueret system er altid forsinket - det er det, som definerer det...
11. “ We define a distributed system as one in which hardware or software components communicate and coordinate their actions only by passing messages.
12. HTTP Hyper Text Transfer Protocol
13. 200 The request has succeeded.
14. 404 Not Found
15. 500 Internal Server Error
17. Webservices Hvordan vil I definere en Webservice?
18. “ A software system designed to support interoperable machine-to-machine interaction over a network
19. “ A web service as an interface in a machine-processable format (WSDL). Other systems interact with the web service in a manner described by its description using SOAP messages, typically conveyed using HTTP with an XML serialization.
20. XML Extensible Markup Language bruges blandt andet når I henter hjemmesider. Det er ofte brugt med SOAP og har været en de-facto standard i rigtig lang tid. Det er dog oftest tungt at indlæse - hvorfor JSON er begyndt at vinde indpas i rigtig mange applikationer. Udvekslingsformater JSON JavaScript Object Notation er et sprog, som er utrolig nemt at skrive og læse - og næsten ikke fylder noget. Langt de fleste sprog har parsers, som kan konvertere JSON direkte til objekter og arrays og det er derfor blevet udbredt ganske hurtigt.
21. JSON {"menu": { "id": "file", "value": "File", "popup": { "menuitem": [ {"value": "New", "onclick": "CreateNewDoc()"}, {"value": "Open", "onclick": "OpenDoc()"}, {"value": "Close", "onclick": "CloseDoc()"} ] } XML <menu id="file" value="File"> <popup> <menuitem value="New" onclick="CreateNewDoc()" /> <menuitem value="Open" onclick="OpenDoc()" /> <menuitem value="Close" onclick="CloseDoc()" /> </popup> </menu>
22. Serialisering
23. thanks! Spørgsmål? Skriv til mig på: @henrikthorn ht.itm@cbs.dk