Copyright © 2003 Benjamin Cassan-de Gorostarzu
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".
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List of Tables
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WISUPDecode is a graphical Java decoder for the SS7 ISUP protocol, under GPL license. Given an hexadecimal dump of a message, it tries to decode it according to a selected decoder.
Warning | |
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This application is not a validator. It can successfully decode invalid messages. This is mainly a tool for reading (and also writing) dumps of messages. Main things that are not checked:
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Some features:
Support for several decoders, dynamically managed. New decoders can easily be integrated.
Portability (Java application).
Several possible languages for the interface (currently two, but anybody can add a new language).
Three decoders supported:
ETSI [ETS 300 356-1 [ITU Q.761 to Q.764 (1993) modified]],
ANSI [ANSI T1.113-1995],
BELLCORE [GR-CORE-317 (1994 issue)] and [GR-CORE-394 (1994 issue)].
Under GPL license :-)
See the list of supported messages and parameters for each ISUP variant.
Thanks to Joe Ratterman, who wrote two of the current decoders ANSI and BELLCORE), and who updated the old applet code for the three decoders. His web site is running the three applets.
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WISUPDecode is distributed in binary and sources packages. You also need at least one decoder. Like the application, decoders are distributed in binary or sources packages. You can find installation information in the readme.txt file in the package.
Note | |
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Sometimes it is not recommended to install a new version over an older one. See the readme file with the package about this. |
The binary package is named WISUPDecode_X-X-X.zip or WISUPDecode_X-X-X.tgz. Just uncompress it in a directory. You must now have this:
install_dir/readme.txt /changes /Todo /license /COPYRIGHT /wisup.jar /wisup/ /module.jar /protocol.jar /speakers.jar /conf/ /modules.properties /lang/ /string.properties /string_en.properties /string_fr.properties /isup/
WISUPDecode is now installed. To launch it, you must install at least a decoder. See the decoder installation for that.
To launch WISUPDecode, just execute the wisup.jar file with Java:
java -jar wisup.jar
According to the OS and the configuration, it can be possible to directly execute jar files.
When you start WISUPDecode for the first time, a configuration file, WISUPDecode.cfg, is created. Currently this text file is the only way to change the interface language. A property, named language, is set to the desired language. The default is en (English). You can set it to any ISO language code (see [ISO 639]), as en for English, fr for French, etc. There must be a matching string_<language-code>.properties file in the wisup/lang directory.
The source package is named WISUPDecode_X-X-X_src.jar. Uncompress it in a directory. You must now have this:
source_dir/readme.txt /changes /Todo /license /COPYRIGHT /ansiapplet.html /bellapplet.html /etsiapplet.html /main.mf /module.mf /protocol.mf /speakers.mf /WISUPDecode_src.mf /makefile /WISUPDecode.dox /WISUPDecode.xml /wisup/ /conf/ /modules.properties /isup/ /lang/ /string.properties /string_en.properties /string_fr.properties /main/ /*.java /*.form /module/ /*.java /protocol/ /*.java /speakers/ /*.java
The applet files (java and html) are not supported. It was written for a modified version 2.1.0 of WISUPDecode. It is provided for those who wants to hack the code. The makefile is part of this code, and probably do not work with the current code.
You need a Java 2 JDK for compiling the code. I currently use a 1.3.x JDK.
For developing I use NetBeans, a Java OpenSource IDE. The *.form files are XML files used by NetBeans for designing the GUIs of the application. I use ANT for building WISUPDecode. The ANT makefile is WISUPDecode.xml. It defines all the required targets, for WISUPDecode and for the decoders. I strongly suggest to use ANT instead of trying to build everything directly with javac.
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Some targets need the decoders sources. |
If you want to build the Doxygen documentation, you can use the WISUPDecode.dox file. Look at the documentation of Doxygen about the options defined in the dox file (created with the GUI packaged with Doxygen).
The three current decoders are installed in the same way. The installation is detailed for the ETSI decoder.
The binary package is named ets300_356_1_X-X.zip or ets300_356_X-X.tgz. You can install it where you want, but the preferred solution is in wisup/isup directory. After decompression, you must now have this:
install_dir/wisup/isup/ /ets300_356_1.jar /ets300_356_1/ /changes /COPYRIGHT /license /readme.txt
You now need to modify the wisup/conf/modules.properties. The file provided with WISUPDecode is already set up for the three decoders located in wisup/isup/ directory. If you installed your decoder somewhere else, or if you need to change the configuration, follow these steps:
Each decoder is associated with an index. The first decoder has index 0, the second the index 1, etc. According to the current configuration, select the first available index. Lets say index 0.
You must set the two following variables:
Variable | Description | Value |
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decoder.0 | Package name of the decoder | wisup.isup.ets300_356_1 |
decoder.0.path | Path of the package | wisup/isup/ets300_356_1.jar |
These values should be provided by the readme file of the decoder. The path can be set according to the current classpath. The location of the wisup.jar file is automatically added to the classpath, so the value wisup/isup/ets300_356_1.jar for the decoder path can be used. You can also use an URL for the path.
When the modules.properties file is modified, you can launch WISUPDecode. The application checks if the decoders can be loaded at start-up, so you can see if the configuration is valid.
Important | |
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You need the WISUPDecode sources for building the decoders. |
The source package is named ets300_356_1_X-X_src.jar. Uncompress it in the wisup/isup/ directory. You must now have this:
source_dir/wisup/isup/ /ets300_356_1/ /changes /COPYRIGHT /license /readme.txt /ets300_356_1.mf /ets300_356_1_src.mf /*.java
Now refer to the WISUPDecode source installation for building the decoder. Some ANT makefile targets are defined for building each decoder.
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This chapter will help you to quickly use WISUPDecode for decoding your ISUP messages.
There is several decoders available for decoding messages. Three are currently available on the WISUPDecode web site:
ETSI decoder [ETS 300 356-1 [ITU Q.761 to Q.764 (1993) modified]],
ANSI decoder [ANSI T1.113-1995],
BELLCORE decoder [GR-CORE-317 (1994 issue)] and [GR-CORE-394 (1994 issue)].
It is not require to install all the decoders. At least one is required for starting the application. If you want to select another decoder than the default one, use the menu .
Before decoding a message, you have to configure the kind of data at the beginning of the message. A message is represented by hexadecimal bytes (2 characters), separated by spaces. Example of an IAM message (ETSI): 01 00 33 02 0A 06 02 00 05 81 00 33 55 F9.
The message content can be preceded by two fields:
You can paste the message dump in the main panel of the application. There is no cut/copy/paste menu yet. You can also open a text file with the data.
Then, if the message tag is provided, just use the menu for decoding the message. If the message tag is not in the data, the menu will display the message selection dialog box, for selecting the message to decode.
The main panel displays the decoded message, each recognized field described. The hexa dump panel displays the original dump message with specific fields highlighted:
You can save the decoded message in a file. Note that the content of the dump panel is not saved.
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This chapter describes the graphical interface of the application.
Table 4.1. Menu entries
File | Menu for opening/saving data. |
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Edit | Not available. |
Decode | Menu for decoding functions. |
Options | Menu for changing options. |
Help | Menu for the help. |
Table 4.2. File menu entries
Table 4.3. Decode menu entries
Clean data | Remove from the current data all characters that are not hexadecimal (others than [0-9a-fA-F], group values for having a list of bytes values (xx xx xx xx). | ||||
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Clean and reverse bytes | Same as Clean data, but also reverse bytes: 01 02 becomes 02 01. | ||||
Decode message | Decode the current data. Only available if the message
tag is part of the data (see the menu ).
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Select message | Launch the Message
selection dialog box. Only available if the message tag
is not part of the data (see the menu ).
When the message is selected, the data are decoded according
to the message selection.
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Table 4.4. Options menu entries
Decoder | Menu for the decoder selection. |
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Content | Menu for selecting specific fields in the raw data. |
Font size | Menu for changing the font size. |
This menu lists the available decoders. You can select the decoder you want to use. There is at least one decoder in the list. See the decoder installation for installing decoders.
Table 4.5. Content menu entries
CIC | Select it if the CIC is at the beginning of the data. The CIC is supposed to be the 2 first bytes of the data. |
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Message type | Select it if the message tag is in the data. If selected, the decoder will read it for selecting the type of the message to decode. If not selected, the Message Selection Dialog Box will ask the message type to use for decoding. |
Table 4.7. Help menu entries
Contents | Not available (will be this help) |
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About... | Call the About dialog box. |
The status bar is separated in 2 parts:
The left part is used for displaying messages, mainly error messages or warnings.
The right part displays the active decoder.
The main panel is used for displaying the raw data to decode and the decoded data. The content can be freely modified by the user. The content can come from a text file, and can be saved.
Raw data is represented by hexadecimal bytes (2 characters), separated by spaces. This is probably the most common representation. The message content can start with the CIC and the message tag byte.
It is not require to have a "clean" dump of the message. Extra characters that are not hexadecimal are removed before decoding.
Warning | |
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There is no check on the modification state of the current data. That means the application will not prompt you if you want to quit with unsaved data. |
The decoded data is in text format, with simple visual formatting:
CIC : 00 00 (0) IAM (Initial Address Message) (1) [ (71) 00 22 00 FF 03 02 09 08 83 20 12 44 ... 55 00 00 ] Mandatory fixed parameters : Octet 0 Nature of connection ind. (6) [ (1) 00 ] ......00 no satellite circuit in the connection (0) ....00.. continuity check not required (0) ...0.... outgoing half echo control device not included (0) Octet 1 Forward call ind. (7) [ (2) 22 00 ] .......0 national call (0) .....01. pass along method available (1) ....0... no interworking encountered (SS7 all the way) (0) ...0.... no end-to-end information available (0) ..1..... ISUP used all the way (1) 00...... ISUP preferred all the way (0) .......0 originating access non-ISDN (0) .....00. no indication (0) Octet 3 Calling party's category (9) [ (1) FF ] ........ spare/reserved for national used (-1) Octet 4 Transmission medium requirement (2) [ (1) 03 ] 00000011 3.1 kHz audio (3) 00000010 --> + 2 00001001 --> + 9 Mandatory variable parameters : Octet 7 Called party number (4) [ (8) 83 20 12 44 42 21 21 0F ] 00001000 length 8 1....... odd number of address signals (1) .0000011 national (significant) number (3) 0....... routing to internal network number allowed (0) .010.... spare (2) Called number : 21 44 24 12 12 ST ERROR : bad optional part pointer (9 instead of 10) Optional parameters : Octet 16 Called party number (4) [ (4) 87 70 21 43 ] 00000100 Called party number 00000100 length 4 1....... odd number of address signals (1) ........ spare/reserved for national use (-1) 0....... routing to internal network number allowed (0) .111.... spare (7) Called number : 12 3
Note | |
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The example used for describing the formatting is an ETSI message. |
There is several parts in the decoded data:
The header, with the CIC and the message information.
The pointers.
The mandatory fixed parameters.
The mandatory variable parameters.
The optional parameters.
There is two parts:
The CIC, if it has been set in . The two bytes are displayed, with the decimal value in parenthesis
CIC : 00 00 (0)
The message information:
IAM (Initial Address Message) (1) [ (71) 00 22 00 FF 03 02 09 08 83 20 12 44 42 ... ]
The acronym of the message.
The name of the message, in parenthesis.
The decimal identifier of the message.
The raw content of the message, in brackets (the first value, in parenthesis, is the length of the message).
A pointer has a simple layout:
00000010 --> + 2
The byte of the pointer.
The decimal value of the pointer.
For each parameter, the following information is displayed:
The parameter information:
Octet 1 Forward call ind. (7) [ (2) 22 00 ]
The byte index. The index starts at 0.
The parameter name.
The decimal identifier of the parameter.
The raw content of the parameter, in brackets (the first value, in parenthesis, is the length of the parameter).
Each meaningful bits field of the parameter is displayed on a line:
.......0 national call (0) .....01. pass along method available (1) ....0... no interworking encountered (SS7 all the way) (0) ...0.... no end-to-end information available (0) ..1..... ISUP used all the way (1) 00...... ISUP preferred all the way (0) .......0 originating access non-ISDN (0) .....00. no indication (0)
The value of the bit(s).
The meaning of the value.
The decimal value of the bits-field, in parenthesis.
Note | |
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For parameters with multi-bytes field, as called numbers, etc., the values of the bits are not displayed, only the meaning of the field (as the number): Called number : 21 44 24 12 12 ST |
Note | |
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Sometimes the same decoding is used for different messages. The meaning for each message is given, and the reading must be done according to the message type: .......1 blocking (CGB) / blocking ack. (CGBA) / unblocking (CGU) / unblocking ack. (CGUA) / blocked for maintenance reasons (GRA) (1) |
This panel displays the original message, with specific bytes highlighted:
In red, the identifiers (of message, of optional parameters).
In gray, the pointers.
In blue, the lengths.
This display is useful for a quick overview of the message structure.
This dialog is opened with the menu - . This is available only if the message tag is not provided for the message (see the menu - for the message tag configuration).
If the message tag is not in the data, you have to select the type of the message to decode. This dialog box displays all recognized messages for the current decoder. The decoding will be done according to your selection.
Table of Contents
This decoder is based on [ETS 300 356-1 [ITU Q.761 to Q.764 (1993) modified]]. It was the first decoder written for WISUPDecode.
List of supported messages: ACM, ANM, CFN, CGB, CGBA, CGU, CGUA, CON, COT, CPG, CQM, CQR, GRA, GRS, IAM, INF, INR, REL, RLC, SAM, all the messages without parameters (BLO, BLA, etc.)
List of supported parameters: transmission medium requirement, called party number, subsequent number, nature of connection ind., forward call ind., optional forward call ind., calling party's category, calling party number, redirecting number, information request ind., information ind., continuity ind., backward call ind., cause ind., redirection information, circuit group supervision msg type ind., range and status, transit network selection, event information, circuit state ind., original called number, optional backward call ind., generic number
This decoder is based on [ANSI T1.113-1995]. It has been written by Joseph Ratterman.
List of supported messages: ACM, ANM, CFN, CGB, CGBA, CGU, CGUA, COT, CPG, CQM, CQR, CRA, CRM, CVR, CVT, EXM, FAC, FOT, GRA, GRS, IAM, INF, INR, LPA, PAM, REL, RES, RLC, SUS, all the messages without parameters (BLO, BLA, etc.)
List of supported parameters: Access transport, Called party number, Nature of connection ind., Forward call ind., Calling party's category, Calling party number, Redirecting number, Information request ind., Information ind., Continuity ind., Backward call ind., Cause ind., Redirection information, Circuit group supervision msg type ind., Range and status, User service information, User-to-user information, Suspend / Resume ind., Transit network selection, Event information, Circuit Assignment Map, Circuit state ind., Automatic congestion level, Original called number, Optional backward call ind., User-to-user ind., Service activation, MLPP precedence, Hop counter, Generic number, Generic digits, Carrier Identification, Business Group, Geographical Location, Jurisdiction Information, Generic Name, Notification Indicator, Circuit Group Characteristic Indicators, Circuit Validation Response Indicator, Outgoing Trunk Group Number, Circuit Identification Name, Common Language Location Identification, Originating Line Information, Charge Number, Carrier Selection Information, Network Transport
This decoder is based on [GR-CORE-317 (1994 issue)] and [GR-CORE-394 (1994 issue)]. It has been written by Joseph Ratterman.
List of supported messages: ACM, ANM, CFN, CGB, CGBA, CGU, CGUA, COT, CPG, CQM, CQR, CRA, CRM, CVR, CVT, EXM, FAC, GRA, GRS, IAM, LPA, PAM, REL, RES, RLC, SUS, all the messages without parameters (BLO, BLA, etc.)
List of supported parameters: Access transport, Called party number, Nature of connection ind., Forward call ind., Calling party's category, Calling party number, Redirecting number, Information request ind., Information ind., Continuity ind., Backward call ind., Cause ind., Redirection information, Circuit group supervision msg type ind., Range and status, User service information, User-to-user information, Suspend / Resume ind., Transit network selection, Event information, Circuit Assignment Map, Circuit state ind., Automatic congestion level, Original called number, Optional backward call ind., User-to-user ind., Service activation, MLPP precedence, Hop counter, Generic number, Generic digits, Carrier Identification, Business Group, Geographical Location, Jurisdiction Information, Generic Name, Notification Indicator, Circuit Group Characteristic Indicators, Circuit Validation Response Indicator, Outgoing Trunk Group Number, Circuit Identification Name, Common Language Location Identification, Originating Line Information, Charge Number, Carrier Selection Information, Network Transport
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The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation.
To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
Copyright (c) YEAR YOUR NAME. 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".
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the "with...Texts." line with this:
with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.