Jump to content

File:Message flows.svg

Page contents not supported in other languages.
This is a file from the Wikimedia Commons
From Wikipedia, the free encyclopedia

Original file (SVG file, nominally 682 × 655 pixels, file size: 30 KB)


Summary

Description
English: To visualize protocol layering and protocol suites, the message flows in and between two systems, A and B, are shown in this diagram.

The systems both make use of the same protocol suite. The vertical flows (and protocols) are in system and the horizontal message flows (and protocols) are between systems. The message flows are governed by rules, and dataformats specified by protocols. Each protocol belongs to a functional class and the classes are said to be layered. The blue lines therefore mark the boundaries of the (horizontal) protocol layers. The vertical protocols are not layered because they don't obey the protocol layering principle which states that a layered protocol is designed so that layer n at the destination receives exactly the same object sent by layer n at the source. The horizontal protocols are layered protocols and all belong to the protocol suite. Layered protocols allow the protocol designer to concentrate on one layer at a time, without worrying about how other layers perform. The vertical protocols neednot be the same protocols on both systems, but they have to satisfy some minimal assumptions to ensure the protocol layering principle holds for the layered protocols. This can be achieved using a technique called encapsulation.

Usually, a message or a stream of data is divided into small pieces, called messages or streams, packets, IP datagrams or network frames depending on the layer in which the pieces are to be transmitted. The pieces contain a header area and a data area. The data in the header area identifies the source and the destination on the network of the packet, the protocol, and other data meaningful to the protocol like CRC's of the data to be send, data length, and a timestamp.

The rule enforced by the vertical protocols is that the pieces for transmission are to be encapsulated in the data area of all lower protocols on the sending side and the reverse is to happen on the receiving side. The result is that at the lowest level the piece looks like this: 'Header1,Header2,Header3,data' and in the layer directly above it: 'Header2,Header3,data' and in the top layer: 'Header3,data', both on the sending and receiving side. This rule therefore ensures that the protocol layering principle holds and effectively virtualizes all but the lowest transmission lines, so for this reason some message flows are coloured red. To ensure both sides use the same protocol, the pieces also carry data identifying the protocol in their header.

Created using: Inkscape 0.47 / KDE 4.4.2 / Kubuntu 10.04.
Date 08:37, 6 December 2010 (UTC)
Source Own work
Author Jsoon eu (talk)
Other versions Message flows.png
SVG development
InfoField
 
The source code of this SVG is invalid due to 3 errors.
 
This W3C-invalid diagram was created with Inkscape…important.
 
 This diagram uses embedded text that can be easily translated using a text editor.

Licensing

I, the copyright holder of this work, hereby publish it under the following licenses:
w:en:Creative Commons
attribution share alike
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
  • share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.
GNU head Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.
You may select the license of your choice.

Captions

Add a one-line explanation of what this file represents

Items portrayed in this file

depicts

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current14:51, 6 December 2010Thumbnail for version as of 14:51, 6 December 2010682 × 655 (30 KB)Jsoon euimproves rendering
09:09, 6 December 2010Thumbnail for version as of 09:09, 6 December 2010682 × 655 (30 KB)Jsoon euremove filter
08:37, 6 December 2010Thumbnail for version as of 08:37, 6 December 2010682 × 655 (30 KB)Jsoon eu{{Information |Description = Message flows between two systems using a protocol suite |Source = I (~~~) created this work entirely by myself. |Date = ~~~~~ |Author = ~~~ |other_versions = Message flows.png }}

Metadata