> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/isdn.md). # ISDN parameters ISDN PRI/BRI and Q.931 settings. 35 parameters. ## F | Parameter | Description | | ------------------------ | ------------------------------------------------------------------- | | **Force wake up action** | Force the local ISDN stack to send SABME to bring up the D-Channel. | ## H | Parameter | Description | | ------------------------------------- | ------------------------------------------------------------------- | | **Hardware CPU usage high threshold** | Hardware CPU usage threshold to start dropping all incoming calls. | | **Hardware CPU usage low threshold** | Hardware CPU usage threshold to start dropping some incoming calls. | ## I | Parameter | Description | | ---------------- | ------------------------------------------------------------------------------------- | | **ISDN Variant** | The Variant parameter indicates the protocol variant to be used on a signaling stack. | ## M | Parameter | Description | | --------------------------------------- | ------------------------------------------------------------- | | **Maximum call burst** | Maximum call burst over the rate limit. | | **Maximum calls per second** | Mximum number of calls per second to allow on this NAP. | | **Maximum simultaneous incoming calls** | The maximum number of concurrent incoming calls. | | **Maximum simultaneous outgoing calls** | The maximum number of concurrent outgoing calls. | | **Maximum simultaneous total calls** | The maximum number of concurrent incoming and outgoing calls. | ## O | Parameter | Description | | ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | **Options** | Bitfield-enabled quirks that make the stack non-compliant but can be necessary for interoperability: 16 = Ignore incoming ALERT in Q.931 state 4 User-side 32 = Ignore incoming bearer capability encoding 64 = Ignore DMS CNG presentation rest | ## P | Parameter | Description | | ----------------------------------- | ---------------------------------------------------------------------------- | | **Primary D Channel Line Service** | The line service (trunk) that will be controlled by the ISDN stack instance. | | **Processing delay high threshold** | CPU congestion threshold to start dropping calls. | | **Processing delay low threshold** | CPU congestion threshold to start dropping calls. | ## S | Parameter | Description | | ----------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Side** | The Side parameter is used to define each side of an ISDN stack. | | **SS7 or ISDN: Always Send ALERTING** | Always send ALERTING before CONNECT (ISDN). | | **SS7 or ISDN: Caller name (CNAM) using alternate methods** | Retrieve 'caller name' (CNAM) using supplementary services (ISDN) or with out-of-call methods (SS7). | | **SS7 or ISDN: CNAM collection timeout** | Maximum time to wait for CNAM to be received from network-side. | | **SS7 or ISDN: Information Transfer Capability** | Speech \* Speech (val=0x00) Digital \* Unrestricted digital information (val=0x08) Restricted digital \* Restricted digital information (val=0x09) 3.1 kHz audio \* 3.1 kHz audio (val=0x10) Digital with tones \* Unrestricted digital information w | | **SS7 or ISDN: Network Specific Facilities IE** | Network specific facilities information element in SETUP. | | **SS7 or ISDN: Relay release location from other leg** | Relay release location from other leg. | | **SS7 or ISDN: Send Connected Number IE** | Insert connected number information element (ISDN and SS7). | | **SS7 or ISDN: Send Display IE** | Insert display information element (ISDN and SS7) | | **SS7 or ISDN: Support 2 Calling Number IE** | Support 2 calling numbers in SETUP (ISDN). | ## T | Parameter | Description | | ---------------------- | ----------------------------------------------------------------------------------------- | | **T301 Timer** | Maximum time to wait between a recieved ALERT and a CONNECT. | | **T302 Timer** | Maximum time to wait for incoming overlap call information. | | **T303 Timer** | Maximum time to wait for a response to an outgoing SETUP message. | | **T304 Timer** | Maximum time to wait for call acceptance after sending last overlap call information. | | **T305 Timer** | Maximum time to wait for a RELEASE after a DISCONNECT is sent. | | **T307 Timer** | Maximum time to wait for an ACK after a SUSPEND request. | | **T308 Timer** | Maximum time to wait for a RELEASE\_COMPLETE after a RELEASE is sent. | | **T309 NET5 Timer** | NET5 guard timeout to keep active calls during layer 2 disconnection. | | **T309 Timer** | Guard timeout to keep active calls during layer 2 disconnection. | | **T310 Network Timer** | Maximum time to wait for a ALERT, CONNECT or DISCONNECT after a received CALL PROCEEDING. | | **T313 Timer** | Maximum time to wait for an acknowledge to an outgoing CONNECT. | | **T316 Timer** | Maximum time to wait for an acknowledge to an outgoing RESTART. | --- # Agent Instructions This documentation is published with GitBook. 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