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<!-- Acc Module User's Guide -->

<chapter>

	<title>&adminguide;</title>

	<section>
	<title>Overview</title>
	<para>
		ACC module is used to account transactions information to different
		backends like syslog and <abbrev>SQL</abbrev>. With the separate module
		<quote>acc_radius</quote> support for <acronym>radius</acronym> is enabled.
	</para>
	<para>
		There is some very early support of the <acronym>Diameter</acronym>
		protocol in the <quote>acc_diameter</quote> module, but is not up to date
		with the current Diameter protocols. If you need Diameter support,
		please use the <acronym>ims_charging</acronym> module.
	</para>
	<para>
		To account a transaction and to choose which set of backends to be
		used, the script writer just has to set some flags (see the module
		parameters section for flag definitions <xref linkend="acc.i.params"/>).
		If the accounting flag for a specific backend is set, the acc module
		will then report on completed transaction. A typical usage of the
		module takes no acc-specific script command -- the functionality
		binds invisibly through transaction processing. Script writers just
		need to mark the transaction for accounting with proper setflag.
		Even so, the module allows the script writter to force accounting in
		special cases via some script functions.
	</para>
	<para>
		The accounting module will log by default a fixed set of attributes
		for the transaction - if you customize your accounting by adding more
		information to be logged, please see the next chapter about extra
		accounting - <xref linkend="acc.i.extra-accounting"/>.
	</para>
	<para>
		The fixed minimal accounting information is:
		<itemizedlist>
		<listitem>
			<para>Request Method name</para>
		</listitem>
		<listitem>
			<para>From header TAG parameter</para>
		</listitem>
		<listitem>
			<para>To header TAG parameter</para>
		</listitem>
		<listitem>
			<para>Call-Id</para>
		</listitem>
		<listitem>
			<para>3-digit Status code from final reply</para>
		</listitem>
		<listitem>
			<para>Reason phrase from final reply</para>
		</listitem>
		<listitem>
			<para>Time stamp when transaction was completed</para>
		</listitem>
		</itemizedlist>
		If a value is not present in request, the empty string is accounted
		instead.
	</para>
	<para>
		Note that:
		<itemizedlist>
		<listitem>
			<para>
			A single INVITE may produce multiple accounting reports -- that's
			due to SIP forking feature.
			</para>
		</listitem>
		<listitem>
			<para>
			All flags related to accounting need to be set in request processing
			route - only the "missed-call" flag may be toggled from other
			types of routes.
			</para>
		</listitem>
		<listitem>
			<para>
			If a UA fails in middle of conversation, a proxy will never
			find out about it. In general, a better practice is to account from an
			end-device (such as PSTN gateway), which best knows about call
			status (including media status and PSTN status in case of the
			gateway). However, CDR-base logging has the option to log existing
			information from expired dialogs (the dlg_vars in cdr_extra)
			Please see cdr_expired_dlg_enable parameter - <xref linkend="acc.p.cdr_expired_dlg_enable"/>.
			</para>
		</listitem>
		</itemizedlist>
	</para>
	<para>
		The SQL backend support is compiled in the module.
        </para>
	<section>
		<title>General Example</title>
		<programlisting format="linespecific">
loadmodule "modules/acc/acc.so"
modparam("acc", "log_level", 1)
modparam("acc", "log_flag", 1)

if (uri=~"sip:+40") /* calls to Romania */ {
    if (!proxy_authorize("sip_domain.net" /* realm */,
    "subscriber" /* table name */))  {
        proxy_challenge("sip_domain.net" /* realm */, "0" /* no qop */ );
        exit;
    }

    if (method=="INVITE" &amp;&amp; !check_from()) {
        log("from!=digest\n");
        sl_send_reply("403","Forbidden");
    }

    setflag(1); /* set for accounting (the same value as in log_flag!)
    t_relay(); 	/* enter stateful mode now */
};
</programlisting>
	</section>
	</section>

	<section id="acc.i.extra-accounting">
		<title>Extra accounting</title>
		<section>
			<title>Overview</title>
			<para>
			Along the static default information, ACC modules
			allows dynamical selection of extra information to be logged.
			This allows you to log any pseudo-variable (AVPs, parts of
			the request, etc).
			</para>
		</section>
		<section id="acc-def-syn">
			<title>Definitions and syntax</title>
			<para>
			Selection of extra information is done via
			<emphasis>xxx_extra</emphasis> parameters by specifying the names
			of additional information you want to log. This information is
			defined via pseudo-variables and may include headers, AVPs values
			or other message or system values. The syntax of the parameter is:
			</para>
			<itemizedlist>
				<listitem><para><emphasis>
				xxx_extra = extra_definition (';'extra_definition)*
				</emphasis></para></listitem>
				<listitem><para><emphasis>
				extra_definition = log_name '=' pseudo_variable
				</emphasis></para></listitem>
			</itemizedlist>
			<para>
			The full list of supported pseudo-variables in &kamailio; is
			available at:
			<ulink url="http://www.kamailio.org/wiki/cookbooks/devel/pseudovariables">
			http://www.kamailio.org/wiki/cookbooks/devel/pseudovariables</ulink>
			</para>
			<para>
			Note: For all the ACK processed by tm, the registered callbacks
			(like acc module) will be called with the corresponding INVITE
			transaction contexts as long as this is still available. This means
			that the ACK callbacks will see the AVPs setup for the INVITE
			transaction and not the AVPs setup before t_relay().
			</para>
			<para>
			Via <emphasis>log_name</emphasis> you define how/where the
			<emphasis>data</emphasis> will be logged. Its meaning depends
			of the accounting support which is used:
			<itemizedlist>
				<listitem><para><emphasis>LOG accounting</emphasis> - log_name
				will be just printed along with the data in <emphasis>
				log_name=data</emphasis> format;
				</para></listitem>
				<listitem><para><emphasis>DB accounting</emphasis> - log_name
				will be the name of the DB column where the data will be
				stored.<emphasis>IMPORTANT</emphasis>: add in db
				<emphasis>acc</emphasis> table the columns corresponding to
				each extra data;
				</para></listitem>
				<listitem><para><emphasis>RADIUS accounting</emphasis> -
				log_name will be the AVP name used for packing the data into
				RADIUS message. The log_name will be translated to AVP number
				via the dictionary. <emphasis>IMPORTANT</emphasis>: add in
				RADIUS dictionary the <emphasis>log_name</emphasis> attribute.
				</para></listitem>
				<listitem><para><emphasis>DIAMETER accounting</emphasis> -
				log_name will be the AVP code used for packing the data
				into DIAMETER message. The AVP code is given directly as
				integer, since DIAMETER has no dictionary support yet.
				<emphasis>IMPORTANT</emphasis>:	<emphasis>log_name</emphasis>
				must be a number.
				</para></listitem>
			</itemizedlist>
			</para>
		</section>
		<section>
			<title>How it works</title>
			<para>
			Some pseudo variables may return more than one value (like
			headers or AVPs). In this case, the returned values are
			embedded in a single string in a comma-separated format.
			</para>
		</section>
	</section>

	<section id="acc.i.multi-call-legs">
		<title>Multi Call-Legs accounting</title>
		<section>
			<title>Overview</title>
			<para>
			A SIP call can have multiple legs due forwarding actions. For
			example user A calls user B which forwards the call to user C.
			There is only one SIP call but with 2 legs ( A to B and B to C).
			Accounting the legs of a call is required for proper billing of
			the calls (if C is a PSTN number and the call is billed, user B
			must pay for the call - as last party modifying the call
			destination-, and not A - as initiator of the call. Call
			forwarding on server is only one example which shows the
			necessity of the having an accounting engine with multiple legs
			support.
			</para>
		</section>
		<section>
			<title>Configuration</title>
			<para>
			First how it works: The idea is to have a set of AVPs and for each
			call leg to store a set of values in the AVPs. The meaning of
			the AVP content is strictly decided by the script writer - it can
			be the origin and source of the leg, its status or any other
			related information. If you have a set of 4 AVPS (AVP1, AVP2, AVP3,
			AVP4), then for the "A call B and B forwards to C" example,
			you need to set a different set of values for the AVPs
			for each leg ([A,B] and [B,C]) .
			The script writer must take care and properly insert all
			these AVP from the script (in proper order and with the correct type).
			</para>
			<para>
			When the accounting information for the call will be written/sent,
			all the call-leg pairs will be added (based on the found AVP sets).
			</para>
			<para>
			By default, the multiple call-leg support is disabled - it can be
			enabled just be setting the per-leg set of AVPs via the
			<varname>multi_leg_info</varname> module parameter.
			</para>
		</section>
		<section>
			<title>Logged data</title>
			<para>
			For each call, all the values of the AVP set (which defines a
			call-leg) will be logged. How the information will be actually
			logged, depends of the data backend:
			</para>
			<itemizedlist>
				<listitem>
				<para><emphasis>syslog</emphasis> -- all leg-sets will be added
				to one record string as AVP1=xxx, AVP2=xxxx ,... sets.
				</para>
				</listitem>
				<listitem>
				<para><emphasis>database</emphasis> -- each pair will be
				separately logged (due DB data structure constraints); several
				records will be written, the difference between them being
				only the fields corresponding to the call-leg info.
				</para>
				<note><para>You will need to add in your DB (all acc related
				tables) the columns for call-leg info (a column for each AVP
				of the set).
				</para></note>
				</listitem>
				<listitem>
				<para><emphasis>Radius</emphasis> -- all sets will be added
				to the same Radius accounting message as RADIUS AVPs - for each
				call-leg a set of RADIUS AVPs will be added (corresponding
				to the per-leg AVP set). Note that Radius support is in a
				separate module - acc_radius.
				</para>
				<note><para>You will need to add in your dictionary the
				RADIUS AVPs used in call-leg AVP set definition.
				</para></note>
				</listitem>
			</itemizedlist>
		</section>
	</section>
	<section>
		<title>Call Data Record generation</title>
        <section>
            <title>Overview</title>
                <para>
                In addition to transaction-based logging, it is possible to generate and log Call Data
                Records (CDRs) directly from &kamailio;. Apart from a basic set of CDR fields which
                are always included (covering start time, end time, and duration), the approach allows
                flexible specification of additional fields that should be taken into account using
                the configuration script. This is very similar to how transaction-based logging may
                be customized with the exception that CDRs rely on dialogs instead of transactions
                to store relevant information during a call.
                </para>

                <para>
                In order to set up CDR generation, you must enable the CDR switch and load the dialog
                module. You probably also want to specify a set of pseudo-variables that define more
                relevant CDR fields. Pseudo-variables may be assigned arbitrarily during script
                execution, and the module will make sure that the variable content will be transformed
                into a CDR by the end of the dialog.
                </para>

                <para>
                To use CDR logging in a correct manner, you should only use the dialog-based
                pseudo-variables (dlg_var) from the dialog module. This allows you to save values
                right from the beginning through all requests and replies until termination of the
                call. While not recommended, it is still possible to use other pseudo-variables as
                well. Except for pseudo-variables valid in the call-final transaction, however,
                information given will not be stored in the CDR as they cannot be accessed by the
                end of the call when the CDR is logged.
                </para>

                <para>
				Sometimes, dialogs expire because the UA has a problem and a final message is never
				transmitted. You can toggle on/off the generation of CDR-based logging in such cases
				with only the dlg_vars showing by using the cdr_expired_dlg_enable parameter
				- <xref linkend="acc.p.cdr_expired_dlg_enable"/>. Default behavior is not logging.
                </para>
        </section>
		<section id="acc.i.cdr-extra">
			<title>CDR Extra</title>
					This section is similar to the <quote>LOG accounting</quote> part of
					<xref linkend="acc.i.extra-accounting"/>.
			<section>
				<title>Definitions and syntax</title>
					<para>
					Selection of extra information is done similar to the transaction extra
					<xref linkend="acc-def-syn"/>.
					</para>
					<itemizedlist>
						<listitem><para><emphasis>
						cdr_extra = cdr_extra_definition (';'cdr_extra_definition)*
						</emphasis></para></listitem>
						<listitem><para><emphasis>
						cdr_extra_definition = cdr_log_name '=' pseudo_variable
						</emphasis></para></listitem>
					</itemizedlist>
					See also <xref linkend="acc.p.cdr_extra"/>.
					<para>
					The list with all pseudo-variables in &kamailio; can
					be found at: &kamwikilink;.
					</para>
			</section>
		</section>
		<section id="multi-cdr-call-legs">
			<title>CDR with Multi Call-Legs</title>
			<section>
				<title>Overview</title>
				<para>
				As mentioned in <xref linkend="acc.i.multi-call-legs"/>, a leg represents a parallel
				or forwarded call. In contrast to the normal accounting the cdr logging uses dialogs
				instead of transaction to log data. This may reduce the amount of information
				but it also make it possible to combine all important data in one cdr at
				once. A second mechanism to process multiple data-sets into one cdr is not further
				necessary.
				</para>
			</section>
			<section>
				<title>Configuration</title>
				<para>
				When you route messages multiple times through your proxy (e.g. to
				handle <quote>call-forwardings</quote>) you have to use detect_spirals
				from the dialog modules. Otherwise the proxy can't identify and reuse existing
				dialogs.
				</para>
				<para>
				To get the correct call-forwarding-chain you have to store each cf* with the
				corresponding caller and callee in a dialog based pseudo-variable (dlg_var)
				(e.g. chain=B;cfa;C|C;cfnr;D). Additionally it is necessary to store the
				caller and callee for each leg. All this helps to identify the involved
				phone partners and forwarding chain. When you route such calls multiple times
				to the same Proxy, you could store the caller and callee within an transaction
				based avp and write it into the dialog based dlg_var pv during a 200 INVITE.
				</para>
				<section>
					<title>Example for a spiraled Proxy</title>
					<programlisting format="linespecific">
...
# A calls B (transaction 1)
$avp(caller)='A'
$avp(callee)='B';
$dlg_var(chain)='';

# B cfa C (transaction 2)
$avp(caller)='B'
$avp(callee)='C';
$dlg_var(chain)='B;cfu;C';

# C cfnr D (transaction 3)
$avp(caller)='C'
$avp(callee)='D';
$dlg_var(chain)=$dlg_var(chain) + "|" + "C;cfnr;D";

# C confirms call (200 reply of transaction 2)
$dlg_var(caller) = $avp(caller); #caller='B'
$dlg_var(callee) = $avp(callee); #callee='C'
...
					</programlisting>
				</section>
			</section>
			<section>
				<title>Logged data</title>
				For each call, all dialog corresponding variables will be logged. After a call
				is finished, the generated call data record information will be logged as string
				(VAR1=xxx,VAR2=xxxx,...) to the syslog.
			</section>
		</section>
	</section>
	<section>
		<title>Dependencies</title>
		<section>
			<title>&kamailio; Modules</title>
			<para>
			The module depends on the following modules (in the other words
			the listed modules must be loaded before this module):
			<itemizedlist>
				<listitem>
				<para><emphasis>tm</emphasis> -- Transaction Manager</para>
				</listitem>
				<listitem>
				<para><emphasis>a database module</emphasis> -- If SQL
				support is used.</para>
				</listitem>
				<listitem>
				<para><emphasis>rr</emphasis> -- Record Route, if
				<quote>detect_direction</quote> module parameter is enabled.
				</para>
				</listitem>
				<listitem>
				<para><emphasis>dialog</emphasis> -- Dialog, if
				<quote>cdr_enable</quote> module parameter is enabled.
				</para>
				</listitem>
			</itemizedlist>
			</para>
		</section>
		<section>
			<title>External Libraries or Applications</title>
			<para>
			The following libraries or applications must be installed
			before running &kamailio; with this module loaded:
			</para>
			<itemizedlist>
				<listitem>
				<para>None</para>
				</listitem>
			</itemizedlist>
		</section>
	</section>

	<section id="acc.i.params">
	<title>Parameters</title>
	<!-- Generic ACC parameters -->
	<section id="acc.p.early_media">
		<title><varname>early_media</varname> (integer)</title>
		<para>
		Should be early media (any provisional reply with body) accounted too ?
		</para>
		<para>
		Default value is 0 (no).
		</para>
		<example>
		<title>early_media example</title>
		<programlisting format="linespecific">
...
modparam("acc", "early_media", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.failed_transaction_flag">
		<title><varname>failed_transaction_flag</varname> (integer)</title>
		<para>
		Per transaction flag which says if the transaction should be
		accounted also in case of failure (SIP status code >= 300).
		This flag triggers accouting when the whole transaction fails
		(on the server side).
		</para>
		<para>
		Default value is not-set (no flag).
		</para>
		<example>
		<title>failed_transaction_flag example</title>
		<programlisting format="linespecific">
...
modparam("acc", "failed_transaction_flag", 4)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.failed_filter">
		<title><varname>failed_filter</varname> (string)</title>
		<para>
		A string of failure response codes from 300 to 999
		separated by commas. Failed transaction will not be accounted
		if its response code is in the list even when
		failed_transaction_flag is set.
		</para>
		<para>
		Default value is not-set (failure filtering is off).
		</para>
		<example>
		<title>failed_filter example</title>
		<programlisting format="linespecific">
...
modparam("acc", "failed_filter", "404,407")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.report_ack">
		<title><varname>report_ack</varname> (integer)</title>
		<para>
		Shall acc attempt to account e2e ACKs too ? Note that this is really
		only an attempt, as e2e ACKs may take a different path
		(unless RR enabled) and mismatch original INVITE (e2e ACKs are
		a separate transaction). The flag for accounting has to be set
		for each ACK as well.
		</para>
		<para>
		Default value is 0 (no).
		</para>
		<example>
		<title>report_ack example</title>
		<programlisting format="linespecific">
...
modparam("acc", "report_ack", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.report_cancels">
		<title><varname>report_cancels</varname> (integer)</title>
		<para>
		By default, CANCEL reporting is disabled -- most accounting
		applications wants to see INVITE's cancellation status.
		Turn on if you explicitly want to account CANCEL transactions.
		</para>
		<para>
		Default value is 0 (no).
		</para>
		<example>
		<title>report_cancels example</title>
		<programlisting format="linespecific">
...
modparam("acc", "report_cancels", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.detect_direction">
		<title><varname>detect_direction</varname> (integer)</title>
		<para>
		Controls the direction detection for sequential requests. If
		enabled (non zero value), for sequential requests with upstream
		direction (from callee to caller), the FROM and TO will be swapped
		(the direction will be preserved as in the original request).
		</para>
		<para>
		It affects all values related to TO and FROM headers (body, URI,
		username, domain, TAG).
		</para>
		<para>
		Default value is 0 (disabled).
		</para>
		<example>
		<title>detect_direction example</title>
		<programlisting format="linespecific">
...
modparam("acc", "detect_direction", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_prepare_flag">
		<title><varname>acc_prepare_flag</varname> (integer)</title>
		<para>
		Per transaction flag which says if the transaction may be accounted
		later, with flags set in TM module specific routes (e.g., like
		failure_route). If this flag is not set and acc or missed_call flag
		are not set either in request route block, there is no way to mark the
		request for transaction later unless you set acc_prepare_always. If either acc or missed_call flags are
		set in request route block, there is no need to set this flag.
		</para>
		<para>
		Default value is not-set (no flag).
		</para>
		<example>
		<title>acc_prepare_flag example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_prepare_flag", 5)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_prepare_always">
		<title><varname>acc_prepare_always</varname> (integer)</title>
		<para>
		Prepare all request even if acc_prepare_flag is not set to mark the request for transaction later.
		</para>
		<para>
		Default value is not-set (previous behaviour).
		</para>
		<example>
		<title>acc_prepare_flag example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_prepare_always", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_extra_nullable">
		<title><varname>acc_extra_nullable</varname> (integer)</title>
		<para>
			If set to 1, the database acc extra fields are set to NULL if the
			corresponding script variable is not defined or has $null value. If
			set to 0, the value is saved as empty string (the existing behavior).
		</para>
		<para>
		Database columns may need to be altered to DROP NOT NULL constraints
		and DROP DEFAULT values in order to accept NULL values.
		</para>
		<para>
		Default value is 0.
		</para>
		<example>
		<title>acc_extra_nullable example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_extra_nullable", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.multi_leg_info">
		<title><varname>multi_leg_info</varname> (string)</title>
		<para>
		Defines the AVP set to be used in per-call-leg accounting.
		See <xref linkend="acc.i.multi-call-legs"/> for a
		detailed description of the Multi Call-Legs accounting.
		</para>
		<para>
		If empty, the multi-leg accounting support will be disabled.
		</para>
		<para>
		Default value is 0 (disabled).
		</para>
		<example>
		<title>multi_leg_info example</title>
		<programlisting format="linespecific">
...
# for syslog-based accounting, use any text you want to be printed
modparam("acc", "multi_leg_info",
    "text1=$avp(src);text2=$avp(dst)")
# for mysql-based accounting, use the names of the columns
modparam("acc", "multi_leg_info",
    "leg_src=$avp(src);leg_dst=$avp(dst)")
# for DIAMETER-based accounting, use the DIAMETER AVP ID (as integer)
modparam("acc", "multi_leg_info",
    "2345=$avp(src);2346=$avp(dst)")
...
</programlisting>
		</example>
	</section>
	<!-- SYSLOG specific ACC parameters -->
	<section id="acc.p.log_flag">
		<title><varname>log_flag</varname> (integer)</title>
		<para>
		Request flag which needs to be set to account a transaction via syslog.
		</para>
		<para>
		Default value is not-set (no flag).
		</para>
		<example>
		<title>log_flag example</title>
		<programlisting format="linespecific">
...
modparam("acc", "log_flag", 2)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.log_missed_flag">
		<title><varname>log_missed_flag</varname> (integer)</title>
		<para>
		Request flag which needs to be set to account missed calls via syslog.
		This can be used to e.g. account failures during the call setup phase
		from the callee (client) side, for example if you do forking to several
		destinations.
		</para>
		<para>
		Keep in mind that this flag is reset after branch completion. Therefore
		it is necessary to set it again e.g. in a failure_route if you do serial
		forking and want to log all attempts.
		</para>
		<para>
		Default value is not-set (no flag).
		</para>
		<example>
		<title>log_missed_flag example</title>
		<programlisting format="linespecific">
...
modparam("acc", "log_missed_flag", 3)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.log_level">
		<title><varname>log_level</varname> (integer)</title>
		<para>
		Log level at which accounting messages are issued to syslog.
		</para>
		<para>
		Default value is 1 (L_NOTICE).
		</para>
		<example>
		<title>log_level example</title>
		<programlisting format="linespecific">
...
modparam("acc", "log_level", 2)   # Set log_level to 2 (L_INFO)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.log_facility">
		<title><varname>log_facility</varname> (string)</title>
		<para>
		Log facility to which accounting messages are issued to syslog.
		This allows to easily separate the accounting specific logging
		from the other log messages.
		</para>
		<para>
		Default value is LOG_DAEMON.
		</para>
		<example>
		<title>log_facility example</title>
		<programlisting format="linespecific">
...
modparam("acc", "log_facility", "LOG_DAEMON")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.log_extra">
		<title><varname>log_extra</varname> (string)</title>
		<para>
		Extra values to be logged.
		See section <xref linkend="acc.i.extra-accounting"/> for more details.
		</para>
		<para>
		Default value is NULL.
		</para>
		<example>
		<title>log_extra example</title>
		<programlisting format="linespecific">
...
modparam("acc", "log_extra", "ua=$hdr(User-Agent);uuid=$avp(i:123)")
...
</programlisting>
		</example>
	</section>
	<!-- SQL specific ACC parameters -->
	<section id="acc.p.db_flag">
		<title><varname>db_flag</varname> (integer)</title>
		<para>
		Request flag which needs to be set to account a
		transaction -- database specific.
		</para>
		<para>
		Default value is not-set (no flag).
		</para>
		<example>
		<title>db_flag example</title>
		<programlisting format="linespecific">
...
modparam("acc", "db_flag", 2)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.db_missed_flag">
		<title><varname>db_missed_flag</varname> (integer)</title>
		<para>
		Request flag which needs to be set to account missed calls via database.
		This can be used to e.g. account failures during the call setup phase
		from the callee (client) side, for example if you do forking to several
		destinations.
		</para>
		<para>
		Keep in mind that this flag is reset after branch completion. Therefore
		it is necessary to set it again e.g. in a failure_route if you do serial
		forking and want to log all attempts.
		</para>
		<para>
		Default value is not-set (no flag).
		</para>
		<example>
		<title>db_missed_flag example</title>
		<programlisting format="linespecific">
...
modparam("acc", "db_missed_flag", 3)
...
</programlisting>
		</example>
	</section>
	<section  id="acc.p.db_table_acc">
		<title><varname>db_table_acc</varname> (string)</title>
		<para>
		Table name of accounting successful calls -- database specific. It
		can contain config variables that will be evaluated at runtime.
		</para>
		<para>
		Default value is <quote>acc</quote>
		</para>
		<example>
		<title>db_table_acc example</title>
		<programlisting format="linespecific">
...
modparam("acc", "db_table_acc", "myacc_table")
modparam("acc", "db_table_acc", "acc_$time(year)_$time(mon)")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.db_table_missed_calls">
		<title><varname>db_table_missed_calls</varname> (string)</title>
		<para>
		Table name for accounting missed calls -- database specific. It
		can contain config variables that will be evaluated at runtime.
		</para>
		<para>
		Default value is <quote>missed_calls</quote>
		</para>
		<example>
		<title>db_table_missed_calls example</title>
		<programlisting format="linespecific">
...
modparam("acc", "db_table_missed_calls", "myMC_table")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.db_url">
		<title><varname>db_url</varname> (string)</title>
		<para>
		SQL address -- database specific. If is set to NULL or empty string,
		the SQL support is disabled.
		</para>
		<para>
		Default value is <quote>NULL</quote> (SQL disabled).
		</para>
		<example>
		<title>db_url example</title>
		<programlisting format="linespecific">
...
modparam("acc", "db_url", "mysql://user:password@localhost/kamailio")
...
</programlisting>
		</example>
	</section>
	<section  id="acc.p.acc_method_column">
		<title><varname>acc_method_column</varname> (string)</title>
		<para>
		Column name in accounting table to store the request's method name as
		string.
		</para>
		<para>
		Default value is <quote>method</quote>.
		</para>
		<example>
		<title>acc_method_column example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_method_column", "method")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_from_tag_column">
		<title><varname>acc_from_tag_column</varname> (string)</title>
		<para>
		Column name in accounting table to store the From header TAG parameter.
		</para>
		<para>
		Default value is <quote>from_tag</quote>.
		</para>
		<example>
		<title>acc_from_tag_column example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_from_tag_column", "from_tag")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_to_tag_column">
		<title><varname>acc_to_tag_column</varname> (string)</title>
		<para>
		Column name in accounting table to store the To header TAG parameter.
		</para>
		<para>
		Default value is <quote>to_tag</quote>.
		</para>
		<example>
		<title>acc_to_tag_column example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_to_tag_column", "to_tag")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_callid_column">
		<title><varname>acc_callid_column</varname> (string)</title>
		<para>
		Column name in accounting table to store the request's Callid value.
		</para>
		<para>
		Default value is <quote>callid</quote>.
		</para>
		<example>
		<title>acc_callid_column example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_callid_column", "callid")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_sip_code_column">
		<title><varname>acc_sip_code_column</varname> (string)</title>
		<para>
		Column name in accounting table to store the final reply's numeric code
		value in string format.
		</para>
		<para>
		Default value is <quote>sip_code</quote>.
		</para>
		<example>
		<title>acc_sip_code_column example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_sip_code_column", "sip_code")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_sip_reason_column">
		<title><varname>acc_sip_reason_column</varname> (string)</title>
		<para>
		Column name in accounting table to store the final reply's reason
		phrase value.
		</para>
		<para>
		Default value is <quote>sip_reason</quote>.
		</para>
		<example>
		<title>acc_sip_reason_column example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_sip_reason_column", "sip_reason")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.acc_time_column">
		<title><varname>acc_time_column</varname> (string)</title>
		<para>
		Column name in accounting table to store the time stamp of the
		transaction completion in date-time format.
		</para>
		<para>
		Default value is <quote>time</quote>.
		</para>
		<example>
		<title>acc_time_column example</title>
		<programlisting format="linespecific">
...
modparam("acc", "acc_time_column", "time")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.db_extra">
		<title><varname>db_extra</varname> (string)</title>
		<para>
		Extra values to be logged into database - DB specific.
		See section <xref linkend="acc.i.extra-accounting"/> for more details.
		</para>
		<para>
		Default value is NULL.
		</para>
		<example>
		<title>db_extra example</title>
		<programlisting format="linespecific">
...
modparam("acc", "db_extra", "ct=$hdr(Content-type); email=$avp(s:email)")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.db_insert_mode">
		<title><varname>db_insert_mode</varname> (integer)</title>
		<para>
		If set to 1, use INSERT DELAYED to add records to accounting tables
		when the DB driver has support for it. If no INSERT DELAYED support
		is offered by DB driver, then standard INSERT is used. Beware that
		MySQL InnoDB engine doesn't support INSERT DELAYED, thus be sure
		the acc tables are defined with different type (e.g., MyISAM).
		</para>
		<para>
		If set to 2, async insert is used if the db driver module has
		support for it and if async_workers core parameter value is greater
		than 0. If not, then standard INSERT is used.
		</para>
		<para>
		Default value is 0 (no INSERT DELAYED nor async insert).
		</para>
		<example>
		<title>db_insert_mode example</title>
		<programlisting format="linespecific">
...
modparam("acc", "db_insert_mode", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_enable">
		<title><varname>cdr_enable</varname> (integer)</title>
		<para>
		Should CDR-based logging be enabled?
		</para>
		<para>
		0 - off (default).
		1 - on.
		</para>
		<example>
		<title>cdr_enable example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_enable", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_skip">
		<title><varname>cdr_skip</varname> (string)</title>
		<para>
		Skip cdr generation for dialogs with this dlg_var set.
		</para>
		<para>
		Default value is NULL.
		</para>
		<example>
		<title>cdr_skip example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_skip", "nocdr")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_expired_dlg_enable">
		<title><varname>cdr_expired_dlg_enable</varname> (integer)</title>
		<para>
		Should CDR-based logging be enabled in case of expired dialogs?
		</para>
		<para>
		0 - off (default).
		1 - on.
		</para>
		<example>
		<title>cdr_expired_dlg_enable example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_expired_dlg_enable", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_start_on_confirmed">
		<title><varname>cdr_start_on_confirmed</varname> (integer)</title>
		<para>
		Should the start time be taken from the time when the dialog is created,
        	or when the dialog is confirmed?
		</para>
		<para>
		0 - use time of dialog creation (default).
		1 - use time of dialog confirmation.
		</para>
		<example>
		<title>cdr_start_on_confirmed example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_start_on_confirmed", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_facility">
		<title><varname>cdr_facility</varname> (integer)</title>
		<para>
		Log facility to which CDR messages are issued to syslog.
		This allows to easily seperate CDR-specific logging from
		the other log messages.
		</para>
		<para>
		Default value is LOG_DAEMON.
		</para>
		<example>
		<title>cdr_facility example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_facility", "LOG_DAEMON")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_extra">
		<title><varname>cdr_extra</varname> (string)</title>
		<para>
		Set of pseudo-variables defining custom CDR fields. See
        <xref linkend="acc.i.cdr-extra"/> for more details.
		</para>
		<para>
		Default value is NULL.
		</para>
		<example>
		<title>cdr_extra example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_extra", "c1=$dlg_var(caller);c2=$dlg_var(callee)"
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_extra_nullable">
		<title><varname>cdr_extra_nullable</varname> (integer)</title>
		<para>
		Should custom CDR fields be saved as NULL?
		</para>
		<para>
		If set to 0, custom CDR fields not defined in config operation (or set to $null) will be saved as empty string.
		If set to 1, custom CDR fields not defined in config operation (or set to $null) will be saved as NULL.
		</para>
		<para>
		Database columns may need to be altered to DROP NOT NULL constraints
		and DROP DEFAULT values in order to accept NULL values.
		</para>
		<para>
		Default value is 0.
		</para>
		<example>
		<title>cdr_extra_nullable example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_extra_nullable", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_start_id">
		<title><varname>cdr_start_id</varname> (string)</title>
		<para>
		Modifying the id which is used to store the start time.
		</para>
		<para>
		Default value is 'start_time'
		</para>
		<example>
		<title>cdr_start_id example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_start_id", "start")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_end_id">
		<title><varname>cdr_end_id</varname> (string)</title>
		<para>
		Modifying the id which is used to store the end time.
		</para>
		<para>
		Default value is 'end_time'
		</para>
		<example>
		<title>cdr_end_id example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_end_id", "end")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_duration_id">
		<title><varname>cdr_duration_id</varname> (string)</title>
		<para>
		Modify the id which is used to store the duration.
		</para>
		<para>
		Default value is 'duration'
		</para>
		<example>
		<title>cdr_duration_id example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_duration_id", "d")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_log_enable">
		<title><varname>cdr_log_enable</varname> (int)</title>
		<para>
		Control if CDR-based accounting should be written to syslog.
		</para>
		<para>
		0 - off.
		1 - on (default).
		</para>
		<example>
		<title>cdr_log_enable example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_log_enable", 0)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdrs_table">
		<title><varname>cdrs_table</varname> (str)</title>
		<para>
		Name of db table to store dialog-based CDRs.
		</para>
		<para>
		Default value is "" (no db storage for dialog-based CDRs).
		</para>
		<example>
		<title>cdrs_table example</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdrs_table", "acc_cdrs")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.time_mode">
		<title><varname>time_mode</varname> (int)</title>
		<para>
		Store additional value related to the time of event.
		</para>
		<para>
		Values can be:
		</para>
		<itemizedlist>
		<listitem>
			<para><emphasis>0</emphasis> -  (default), save only unix
				timestamp for syslog and datetime for database.</para>
		</listitem>
		<listitem>
			<para><emphasis>1</emphasis> - save seconds in time_attr and
				microseconds in time_exten.</para>
		</listitem>
		<listitem>
			<para><emphasis>2</emphasis> - save seconds.milliseconds
				in time_attr.</para>
		</listitem>
		<listitem>
			<para><emphasis>3</emphasis> - save formatted time according
				to time_format parameter, using the output of localtime(). Used for cdr entries too.
			</para>
		</listitem>
		<listitem>
			<para><emphasis>4</emphasis> - save formatted time according
				to time_format parameter, using the output of gmtime(). Used for cdr entries too.
			</para>
		</listitem>
		</itemizedlist>

		<example>
		<title>time_mode example</title>
		<programlisting format="linespecific">
...
modparam("acc", "time_mode", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.time_attr">
		<title><varname>time_attr</varname> (str)</title>
		<para>
		Name of the syslog attribute or database column where to store additional
		value related to the time of event.
		</para>
		<para>
		For db accounting, the column has to be of different types, depending on
		time_mode value. When time_mode is:
		</para>
		<itemizedlist>
		<listitem>
			<para><emphasis>1</emphasis> - time_attr column has to be int.</para>
		</listitem>
		<listitem>
			<para><emphasis>2</emphasis> - time_attr column has to be double.</para>
		</listitem>
		<listitem>
			<para><emphasis>3</emphasis> - time_attr column has to be varchar(128).</para>
		</listitem>
		<listitem>
			<para><emphasis>4</emphasis> - time_attr column has to be varchar(128).</para>
		</listitem>
		</itemizedlist>
		<para>
		For time_mode=1, this attribute is not written in syslog, because time
		value is already unix timestamp, but in db accounting time value is
		datetime and requires a function to get the timestamp.
		</para>
		<example>
		<title>time_attr example</title>
		<programlisting format="linespecific">
...
modparam("acc", "time_attr", "seconds")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.time_exten">
		<title><varname>time_exten</varname> (str)</title>
		<para>
		Name of the syslog attribute or database column where to store extended
		value related to the time of event.
		</para>
		<para>
		It is used now only for time_mode=1 and database column has to be int:
		</para>
		<example>
		<title>time_exten example</title>
		<programlisting format="linespecific">
...
modparam("acc", "time_exten", "microsecs")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.time_format">
		<title><varname>time_format</varname> (str)</title>
		<para>
		Specify the format to print the time for time_mode 3 or 4.
		</para>
		<para>
		Default value is %Y-%m-%d %H:%M:%S".
		</para>
		<example>
		<title>time_format example</title>
		<programlisting format="linespecific">
...
modparam("acc", "time_format", "%Y/%m/%d %H:%M:%S")
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.reason_from_hf">
		<title><varname>reason_from_hf</varname> (int)</title>
		<para>
		Tells where to take sip_reason from.  If value is 0,
		sip_reason is taken from status line.  Otherwise, sip_reason
		is taken from Reason header field(s) if present.
		Currently only the first Reason header is used.
		</para>
		<para>
		Default value is 0.
		</para>
		<example>
		<title>reason_from_hf</title>
		<programlisting format="linespecific">
...
modparam("acc", "reason_from_hf", 1)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.clone_msg">
		<title><varname>clone_msg</varname> (int)</title>
		<para>
		If set to 1, request structure from transaction is cloned temporarily
		in the callback to get acc attributes. It is required if you account
		values from SIP headers to avoid concurrent access to the shared memory
		transaction structure, specially when accounting 1xx events. If set to
		0, it uses directly the shared memory structure, be sure you store all
		needed attributes in AVPs/XAVPs inside request route.
		</para>
		<para>
		Default value is 1.
		</para>
		<example>
		<title>clone_msg</title>
		<programlisting format="linespecific">
...
modparam("acc", "clone_msg", 0)
...
</programlisting>
		</example>
	</section>
	<section id="acc.p.cdr_on_failed">
		<title><varname>cdr_on_failed</varname> (int)</title>
		<para>
		If set to 1, the module stores the CDR for a failed dialog (calls not
		answered). If set to 0, those records are not stored, only those for
		answered calls.
		</para>
		<para>
		Default value is 1.
		</para>
		<example>
		<title>cdr_on_failed</title>
		<programlisting format="linespecific">
...
modparam("acc", "cdr_on_failed", 0)
...
</programlisting>
		</example>
	</section>
	</section>

	<section>
	<title>Functions</title>
	<section id="acc.f.acc_log_request">
		<title>
			<function moreinfo="none">acc_log_request(comment)</function>
		</title>
		<para>
		<function moreinfo="none">acc_request</function> reports on a request,
		for example, it can be used to report on missed calls to off-line users
		who are replied 404 - Not Found. To avoid multiple reports on UDP
		request retransmission, you would need to embed the
		action in stateful processing.
		</para>
		<para>
		Meaning of the parameters is as follows:</para>
		<itemizedlist>
		<listitem>
			<para><emphasis>comment</emphasis> - Comment to be appended.
			The string can contain any number of pseudo-variables.
			</para>
		</listitem>
		</itemizedlist>
		<para>
		This function can be used from ANY_ROUTE.
		</para>
		<example>
		<title>acc_log_request usage</title>
		<programlisting format="linespecific">
...
acc_log_request("Some comment");
$var(code) = 404;
$avp(reason) = "Not found";
acc_log_request("$var(code) Error: $avp(reason)");
...
</programlisting>
		</example>
	</section>
	<section id="acc.f.acc_db_request">
		<title>
			<function moreinfo="none">acc_db_request(comment, table)</function>
		</title>
		<para>
		Like <function moreinfo="none">acc_log_request</function>,
		<function moreinfo="none">acc_db_request</function> reports on a
		request. The report is sent to database at <quote>db_url</quote>, in
		the table referred to in the second action parameter.
		</para>
		<para>
		Meaning of the parameters is as follows:
		</para>
		<itemizedlist>
		<listitem>
			<para><emphasis>comment</emphasis> - Comment to be appended.
			The string can contain any number of pseudo-variables.
			</para>
		</listitem>
		<listitem>
			<para><emphasis>table</emphasis> - Database table to be used. It
			can contain config variables that are evaluated at runtime.</para>
		</listitem>
		</itemizedlist>
		<para>
		This function can be used from ANY_ROUTE.
		</para>
		<example>
		<title>acc_db_request usage</title>
		<programlisting format="linespecific">
...
acc_db_request("Some comment", "SomeTable");
acc_db_request("Some comment", "acc_$time(year)_$time(mon)");
acc_db_request("$var(code) Error: $avp(reason)", "SomeTable");
...
</programlisting>
		</example>
	</section>
	<section id="acc.f.acc_request">
		<title>
			<function moreinfo="none">acc_request(comment, table)</function>
		</title>
		<para>
		Wrapper around <function moreinfo="none">acc_log_request</function>
		and <function moreinfo="none">acc_db_request</function> functions,
		writing the accounting record to LOG and DATABASE backends. If
		<quote>db_url</quote> parameter is not set, the acc record is written
		only to LOG backend.
		</para>
		<para>
		Meaning of the parameters is as follows:
		</para>
		<itemizedlist>
		<listitem>
			<para><emphasis>comment</emphasis> - Comment to be used for
			generating the SIP response code and text fields, if in the
			format <quote>CODE TEXT</quote>. The CODE should be a valid
			SIP response code (100..699). The TEXT can be one or many words.
			If CODE is missing, then 0 is used.
			The parameter can contain pseudo-variables.
			</para>
		</listitem>
		<listitem>
			<para><emphasis>table</emphasis> - Database table to be used. It
			can contain config variables that are evaluated at runtime.</para>
		</listitem>
		</itemizedlist>
		<para>
		This function can be used from ANY_ROUTE.
		</para>
		<example>
		<title>acc_db_request usage</title>
		<programlisting format="linespecific">
...
acc_request("100 Received", "acc");
acc_request("100 Received", "acc_$time(year)_$time(mon)");
acc_db_request("$var(code) $avp(reason)", "acc");
...
</programlisting>
		</example>
	</section>
	</section>
</chapter>