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=== Information for upgrading from Zaptel to DAHDI    ===
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As announced in early 2008, Digium is renaming the Zaptel telephony
interface project to DAHDI (Digium Asterisk Hardware Device Interface)
to accommodate the desires of the owner of the Zaptel trademark for
telephony purposes.

This version of Asterisk can be built using either Zaptel or DAHDI,
and has many changes to make the use of DAHDI as easy as possible for
existing users with dialplans, CDR parsers, AMI applications, and
others that expect Zaptel to be in use.

First, the modules that directly use services from Zaptel/DAHDI have been
renamed; the new names are:

  chan_zap.so -> chan_dahdi.so
  app_zapbarge.so -> app_dahdibarge.so
  app_zapras.so -> app_dahdiras.so
  app_zapscan.so -> app_dahdiscan.so
  codec_zap.so -> codec_dahdi.so

However, in spite of the file name changes, the channels and
applications provided by these modules can still be used with 'Zap'
style names; see below for more information.

Second, there are have been a number of efforts made to ensure that
existing systems will not have to have any major configuration changes
made solely because Asterisk was built against DAHDI instead of
Zaptel. This includes:

chan_dahdi.so:

  This module will determine which channel name ('Zap' or 'DAHDI')
  should be used for incoming and outgoing channels based on the
  build-time choice of telephony drivers. However, if you wish to
  continue using the 'Zap' channel name even though you built Asterisk
  against the DAHDI drivers, you can add the following line to the
  [options] section of your /etc/asterisk/asterisk.conf file:

    dahdichanname = no

  All CLI commands that begin with 'zap' are now available as 'dahdi'
  commands as well; the 'zap' variants will report that they are
  deprecated the first time you use each one in an Asterisk instance,
  but they will otherwise operate just as they did in previous versions.

  All Asterisk Manager Interface (AMI) actions that begin with 'Zap'
  are also available with 'DAHDI' prefixes.

  The ZapSendKeypadFacility dialplan application is now available as
  DAHDISendKeypadFacility as well; the Zap variant will report a deprecation
  warning but will otherwise operate as it did it in previous
  versions.

  The configuration for the channel driver will be read from
  /etc/asterisk/chan_dahdi.conf unless 'dahdichanname' has been set to
  'no' in asterisk.conf; if that is done, then the configuration will
  be read from /etc/asterisk/zapata.conf, just as it was in previous
  versions.

app_dahdibarge.so:

  The ZapBarge application is now available as DAHDIBarge as well; the
  ZapBarge variant will report a deprecation warning when used, but
  will otherwise operate as it did in previous versions. Regardless of
  which application name is used, the application will restrict itself
  to channels of the proper type, based on the 'dahdichanname' setting
  in asterisk.conf.

app_dahdiras.so:

  The ZapRAS application is now available as DAHDIRAS as well; the
  ZapRAS variant will report a deprecation warning when used, but will
  otherwise operate as it did in previous versions. Regardless of
  which application name is used, the application will restrict itself
  to channels of the proper type, based on the 'dahdichanname' setting
  in asterisk.conf.

app_dahdiscan.so:

  The ZapScan application is now available as DAHDIScan as well; the
  ZapScan variant will report a deprecation warning when used, but will
  otherwise operate as it did in previous versions. Regardless of
  which application name is used, the application will restrict itself
  to channels of the proper type, based on the 'dahdichanname' setting
  in asterisk.conf.

app_flash.so:

  This application has not had any name changes, but will report its
  usage (via 'show application flash') as being for either DAHDI or
  Zaptel channels based on the 'dahdichanname' setting in
  asterisk.conf.

app_chanspy.so:

  This application will transparently create 'DAHDI' or 'Zap' channels
  as needed, based on the 'dahdichanname' setting in asterisk.conf.

app_meetme.so:

  This application will transparently create 'DAHDI' or 'Zap' channels
  as needed, based on the 'dahdichanname' setting in asterisk.conf.
