Please Whitelist This Site?

I know everyone hates ads. But please understand that I am providing premium content for free that takes hundreds of hours of time to research and write. I don't want to go to a pay-only model like some sites, but when more and more people block ads, I end up working for free. And I have a family to support, just like you. :)

If you like The TCP/IP Guide, please consider the download version. It's priced very economically and you can read all of it in a convenient format without ads.

If you want to use this site for free, I'd be grateful if you could add the site to the whitelist for Adblock. To do so, just open the Adblock menu and select "Disable on tcpipguide.com". Or go to the Tools menu and select "Adblock Plus Preferences...". Then click "Add Filter..." at the bottom, and add this string: "@@||tcpipguide.com^$document". Then just click OK.

Thanks for your understanding!

Sincerely, Charles Kozierok
Author and Publisher, The TCP/IP Guide


NOTE: Using software to mass-download the site degrades the server and is prohibited.
If you want to read The TCP/IP Guide offline, please consider licensing it. Thank you.

The Book is Here... and Now On Sale!

Get The TCP/IP Guide for your own computer.
The TCP/IP Guide

Custom Search







Table Of Contents  The TCP/IP Guide
 9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)
      9  Network File and Resource Sharing Protocols and the TCP/IP Network File System (NFS)
           9  TCP/IP Network File System (NFS)

Previous Topic/Section
NFS Data Storage and Data Types, and the External Data Representation (XDR) Standard
Previous Page
Pages in Current Topic/Section
1
2
3
Next Page
NFS Server Procedures and Operations
Next Topic/Section

NFS Client/Server Operation Using Remote Procedure Calls (RPCs)
(Page 2 of 3)

RPC Operation and Transport Protocol Usage

When a client wants to perform some type of action on a file on a particular machine, it uses RPC to make a call to the NFS server on that machine. The server accepts the request and performs the action required, then returns a result code and possibly data back to the client, depending on the request. The result code indicates if the action was successful. If it was, the client can assume that whatever it asked to be done was completed. For example, in the case of writing data, the client can assume the data has been successfully written to long-term storage.

NFS can operate over any transport mechanism that has a valid RPC implementation at the session layer. Of course in TCP/IP we have two transport protocols, UDP and TCP. It's interesting to see that NFS has seen an evolution of sorts in its use of transport protocol. The NFSv2 standard says that it operates “normally” using UDP, and this is still a common way that NFS information is carried. NFSv3 says that either UDP or TCP may be used, but NFSv4 specifies TCP to carry data. The nominal registered port number for use by NFS is 2049, but in fact other port numbers are sometimes used for NFS, through the use of RPC's “port mapper” capability.

Key Concept: NFS does not use a dedicated message format, like most other protocols do. Instead, clients and servers use the Remote Procedure Call (RPC) protocol to exchange file operation requests and data.



Previous Topic/Section
NFS Data Storage and Data Types, and the External Data Representation (XDR) Standard
Previous Page
Pages in Current Topic/Section
1
2
3
Next Page
NFS Server Procedures and Operations
Next Topic/Section

If you find The TCP/IP Guide useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to consider purchasing a download license of The TCP/IP Guide. Thanks for your support!
Donate $2
Donate $5
Donate $10
Donate $20
Donate $30
Donate: $



Home - Table Of Contents - Contact Us

The TCP/IP Guide (http://www.TCPIPGuide.com)
Version 3.0 - Version Date: September 20, 2005

© Copyright 2001-2005 Charles M. Kozierok. All Rights Reserved.
Not responsible for any loss resulting from the use of this site.