Lecture12n - COT 4600 Operating Systems Spring 2011 Click...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Click to edit Master subtitle style 8/1/11 Lecture 12 COT 4600 Operating Systems Spring 2011 Dan C. Marinescu Office: HEC 304 Office hours: Tu-Th 5:00 – 6:00 PM
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Lecture 12 8/1/11 n Last time: ¨ Client-server organization ¨ Intermediaries; Trusted Intermediaries; Thin clients ¨ Issues § Heterogeneity; little-endian and big-endian representation § Timing, response time. ¨ Examples: Event service, X11; Trusted intermediaries: Email, File Systems, Web Today ¨ Today ¨ Peer-to-peer systems ¨ Remote Procedure Call ¨ Strategies for name resolution ¨ Case study: DNS – Domain Name Service ¨ Case study: NFS – Network File System ¨ Next time n Virtualization Lecture 12 – Tuesday, February 22, 2011 22
Background image of page 2
Lecture 12 8/1/11 33 3 Remote procedure call (RPC) n Support inter-process communication of remotely located processes and allows implementation of client-server systems (RFC 1831) n Preserve the semantics of a local procedure call. n To use an RPC a process may use a special service: PORTMAP or RPCBIND available at port 111. A new RPC service uses the portmapper to register. The portmapper also allows a service lookup. n If the process knows the port number of the RPC it may call directly. n RPC/TCP and also RPC/UDP n Messages ¨ must be well-structured; contain the identification of the specific RPC ¨ are addressed to an RPC demon listening at an RPC port. n A machine independent representation of data & external data representation standard (XDR).
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Lecture 12 8/1/11 44 4
Background image of page 4
Lecture 12 8/1/11 55 5 RPC semantics n At least once ' the client stub resends a message up to a given number of times until it receives a message from the server; is no guarantee of a response ¨ the server may end up executing the a request more than once ¨ suitable for side-effect free operations n At most once O a message is acted upon at most once. ¨ If the timeout set for receiving the response expires then an error code
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 07/30/2011 for the course COP 4600 taught by Professor Montagne during the Spring '08 term at University of Central Florida.

Page1 / 14

Lecture12n - COT 4600 Operating Systems Spring 2011 Click...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online