Configuration Options

To change ASN1VE decoding and editing options, use the Configure option.

1. Click the Edit option from the File Operations toolbar.

2. Select the Configure option (Ctrl + J for a shortcut):

3. The configuration option dialog box will be displayed which will allow the selection of decoding and other options for ASN1VE:

Decoding Tab

Decode Options: The various options are described as follows:

Decode single message from file: ASN1VE will decode the first message in the file and ignore the rest of the data.
Decode multiple messages from file: ASN1VE will continue trying to decode messages from the file until either a) end of file (EOF) is reached, or b) a decode error occurs. This is the default behavior.
Decode multiple messages from a fixed size block: ASN1VE will decode a series of messages from fixed size blocks. Selection of this option will also enable the other options related to fixed size blocks.
Decode a single message from a fixed size block: ASN1VE will decode a single message from each fixed size block and ignore the rest of the data in the block. Selection of this option will also enable the other options related to fixed size blocks.

Fixed Size Block Options: These options are related to messages that are stored in fixed-sized blocks. Several known Call Detail Record (CDR) formats use this type of storage. All of these options are available only when one of the fixed size block decoding options described above is selected.

Size of block: This field accepts the value of the block size in bytes. The maximum possible value for this field is 50000000.
Number of blocks to be decoded: This field accepts the value for the number of blocks to be decoded. By default, ASN1VE will decode all the blocks in the message.

Skip Message Bytes: This option allows a fixed number of bytes to be ignored before beginning to decode an ASN.1 message. It can be used in situations where a non-ASN.1 header is inserted before the message data starts (for example, an H.323 Q.931 message). A fixed or a repeating offset (or both) can be specified. The fixed offset is a one-time offset that occurs at the beginning of the data file. The repeating offset is an offset that occurs before each ASN.1 record in the file.

Changing padding byte value: By selecting this option, the user will be able to define additional padding byte values which usually appear between messages or at the end of a message. Padding bytes can be specific in hex format only and only one padding byte can be defined at any given time (for example, FF). The default padding byte value is 00.

Disable BCD (Binary Coded Decimal) conversion: This option is used for the following assignments:
TBCDSTRING ::= OCTET STRING
BCDString ::= OCTET STRING

The assignments can have constraints. By default, ASN1VE will do BCD or TBCD conversion of values for display and editing. By selecting this option, ASN1VE will disable the BCD type conversion which will cause the values to be displayed as normal OCTET STRING's.

Force OCTET STRING's to be interpreted as BCD strings: This option forces all BCD related strings to be interpreted as standard BCD strings. This means packed digits within bytes are not reversed upon decoding.

Force OCTET STRING's to be interpreted as TBCD strings: This option forces all BCD related strings to be interpreted as standard TBCD strings. This means packed digits within bytes are reversed upon decoding.

Disable Automatic Open Type decoding: This option is used to disable the decoding of open type data in a message. By default, ASN1VE will try to decode the open type data using the appropriate ASN.1 type (searched by ASN1VE).

Maximum Number of Repeating Record to Decode at One Time: This option is used to set the maximum number of records in a repeating item (an item of type SEQUENCE OF or SET OF) that are decoded at one time in the tree view. When this limit is reached, a special icon labeled "More..." is added to the end of the list. Clicking this icon causes the next set of records to be decoded. This option was added because it can take an extremly long time to build up a tree view for CDR files containing a large number of records. This option makes it possible to decode segments of the file in stages in reasonable amounts of time.

Other Tab

Items under the Other tab include XML-related options and other options.

XML Options

XML Data Format: This option is used to select either standard XML or XML that is compliant with the ASN.1 XML Encoding Rules (XER) format. The primary difference is that enumerated items in ASN.1 XER format are represented as empty elements (i.e. <element/>) as opposed to space-separated tokens in standard XML.

Disable Root Element for Single Message File: If an ASN.1 message file contains only a single encoded record, it can be translated to XML without the need for a special wrapper outer element. Checking this box allows this to be done. Otherwise, the root element shown in the next option is added as the outer element.

Root Element Name: This is the name of a special outer level wrapper element that is used wrap a collection of XML-encoded ASN.1 records. A common use-case for this is the case of a CDR file containing multiple CDR records. In order to create a well-formed XML document, it is necessary to wrap these records with a single outer level element.

Print ASCII for Printable Hex Values: This controls how binary content is displayed if no schema is assigned to provide type information. By default, binary values are displayed as hexadecimal text. If this option is enabled and the content is found to contain all valid ASCII printable characters, the content is displayed as text.

Insert Empty XML Elements for Missing Optional Elements: Enabling this option causes empty XML elements (i.e. <element/>) to be added to the generated XML for missing optional elements. By default, nothing is added to the generated XML document for missing optional elements.

Insert XML Elements with Default Values for Missing Elements: Enabling this option causes XML elements with default values to be added to the generated XML if the ASN.1 specification of the element contains a DEFAULT value and the element is not present in the ASN.1 encoded data. By default, nothing is added to the generated XML document for missing elements that have default values.

Remove all Whitespace between Elements: This option causes all ignorable whitespace (CR/LF's and indentation spaces) between elements to be removed from the generated XML. This makes the XML more compact for transmission.

BIT STRING Content Format: This option controls whether bit string data is formatted in binary form (1's and 0's) or hexadecimal form.

Other Options

XML/Text View Record Display: This option controls whether all records in a file are displayed in XML or Text view or only the currently selected record. When a large file is loaded, it is sometimes not possible to display all of the record in XML or Text view due to the resources required. This option makes it possible to display only the selected record in a multi-record file in these views.

Check UTCTime and GeneralizedTime value format: This option is used to enable the strict format checking of the value entered for a time string. By default, ASN1VE will only check for valid characters without checking the overall format.

Maintain message and ASN.1 directories as separate directories: This option will cause ASN1VE to remember the last directory a message file was selected from and the last directory an ASN.1 schema files was selected from as separate items. The default is to remember only the last directory a files was selected from as a single item. This is the default directory that is recalled when a file open operation is done.