Creating and Modifying Entries to Call Routing Tables

Specifies the admin state of the Call Route. Valid entry: Enable (enables the call route entry for routing the call, displays in configuration header as  ) or Disable (disables the call route entry from being used, displays in the configuration header as ).

Priority of the route from 1 (highest) to 10 (lowest).

Higher priority routes are matched against before lower priority routes regardless of the order of the routes in the table.

Call Priority is used for emergency (911) calls in the U.S. and other countries. This field is used if the Priority header is not received in the ingress SIP INVITE and for PSTN interfaces. The default value is Normal. When integrating with E911 providers, Priority may have to be set to Emergency.

Specifies the Transformation Table to be used for this routing entry. This drop down list is populated from the entries in the Transformation Table.

Select an optional time of day table to use with the call route. All Time of Day tables are included in this drop down list. For details on Time of Day, refer to Working with Time of Day.

Specifies the destination type for calls using this route. Valid selections: Normal, Registrar Table, Deny, or Trunk Group.

Normal. Call routes to normal types such as ISDN or SIP signaling groups. Specify a list of signaling groups through Destination Signaling Groups.

Registrar Table. Call routes to a signaling group that contains the registrar table.

Deny. Call routes to a specific Q.850 cause code are rejected. Through the Deny Q.850 Cause Code field, select the specific Q.850 Cause code. When Deny is selected, the Deny Q.850 Cause Code field is displayed.

Trunk Group. Calls are routed to an incoming trunk group destination using the associated signaling group. This routing entry should be selected in order to route calls to a trunk group. When Trunk Group is selected, Fork Call and Destination Signaling Groups options are not available.

Specifies the Q.850 Cause Code for which the call is rejected. Select from the drop down list. This field is displayed only when Deny is selected as Destination Type.

Specifies which Message Translation Table to use.

Specifies which Cause Code Reroute table to use.

Specifies whether or not forked calls should clear when one of the forked calls is forwarded.

Specifies whether or not to fork a call if this route is selected

Specifies the Signaling Groups used as the destination of calls.

The first operational Signaling Group from the list will be chosen to place the call.

Enables a maximum time (set in the Maximum Call Duration field) in which a call can stay in the connected state. This field provides another safeguard against stuck calls (i.e., if a call is up for two days and most likely not meant to stay connected).

Valid entry: Enabled (any call using that particular call route will disconnect after the configured duration in the connected state) or Disabled (default). 

The maximum time (in minutes) in which a call can stay in the connected state. This field is available only when Enable Maximum Call Duration is set to Enabled.  Valid entry: 1 - 10080 minutes.

Media Mode enables you to choose how the SBC handles call signaling and Audio/Fax media stream during a call. Five options are available:

DSP (default entry). The SBC uses DSP resources for media handling (transcoding) but it does not facilitate the capabilities/features between endpoints that are not supported within the SBC (codec/capability mismatch). When DSP is configured, the Signaling Groups enabled to support DSP are attempted in order. To enable a Signaling Group for DSP mode, see Creating and Modifying SIP Signaling Groups.

Proxy. The SBC will proxy or switch the media stream between endpoints and let the endpoints negotiate common media capabilities and handle unsupported/unknown audio codecs. The media flows through the SBC without using DSP resources. For example, this mode is used when both inbound and outbound calls are SIP and both Signaling Groups are enabled for Proxy mode. If one Signaling Group has Proxy mode disabled or one of the inbound Signaling Groups is TDM, the call is rejected. Route configuration does not allow Destination Signaling Groups of TDM type if Stream Mode is set to Proxy. The failover mechanism can then be used to re-route to another Signaling Group. We strongly recommend using Proxy preferred over DSP mode since it allows the same routing entry with different Signaling Groups.

DSP preferred over Proxy. The SBC prefers to use DSP resources, rather than proxy or switch the media stream between endpoints. This mode is chosen during the call setup based on the call routing, and used for call routes where the inbound call route is both TDM and/or SIP (this avoids duplicate call routes). If the inbound Signaling Group is a SIP Signaling Group not enabled for DSP, then Proxy is used. NOTE: If RTP encryption/decryption is expected, it is necessary to set the Proxy SRTP Handling field to 'Local', so that encryption/decryption is supported when switching to proxy.

Proxy preferred over DSP. The SBC prefers to proxy the media stream between endpoints rather than choosing DSP mode (which uses the DSP resource). This mode is chosen during the call setup based on the call routing result, and used for call routes where the inbound call route is both TDM and/or SIP (this avoids duplicate call routes). If the inbound or outbound Signaling Group is NOT in Proxy mode (either SIP signaling group is not enabled for Proxy mode or Signaling Group is TDM), then DSP is used.

Direct: The SBC media flows directly between compatible end-points without using either the SBC processor or a DSP resource.

Disabled. The Audio/Fax media selection process is disabled. When Disabled is selected, the SBC will reject incoming Audio/Fax streams. 

Media Mode enables you to choose how the SBC handles call signaling and Video/Application media stream during a call.

Proxy. The SBC will proxy the media stream between endpoints. The media flows through the SBC without requiring DSP resources. For example, this mode is used when an inbound SIP call includes Video/Application streams and both inbound and outbound SIP Signaling Groups are enabled for Proxy mode. If one Signaling Group has Proxy mode disabled, the stream is disabled. If the outbound Signaling Group is TDM, the call will be connected using Audio/Fax media only and Video/Application media stream will be rejected.  

Direct: The SBC media flows directly between compatible end-points without using either the SBC processor or a DSP resource.

Disabled. The Video/Application Stream Mode is disabled. The SBC will not proxy or switch media stream between endpoints.

The Proxy SRTP Handling option applies SRTP media encryption to a call; this enables communication between end points that are SRTP incompatible. For example, this enables communication if both Calling and Called user agents both support G.711u codec, but they differ in SRTP capability, or one party in the call does not support SRTP at all. Valid entries: Relay or Local. Default: Relay.

This field is displayed only when Proxy, DSP preferred over Proxy, or Proxy preferred over DSP is selected from the Audio Stream Mode drop down list.

Relay: When Relay is selected, the following options are supported:

• For Proxy. Proxy or switches the media stream between endpoints.
• For DSP Preferred over Proxy. Uses DSP resources, rather than proxy or switch the media stream between endpoints.
• Proxy deferred over DSP. Proxies the media stream between endpoints rather than choosing DSP mode.

Local: When Local is selected, SRTP is negotiated automatically for the following: 

• Proxy local SRTP. Proxies or switches the media stream between endpoints using SRTP media encryption on a call leg basis.
• DSP Preferred over Proxy local SRTP. Uses DSP resources in addition to SRTP media encryption, rather than proxy or switch the media stream between endpoints..
• Proxy Local SRTP over DSP. Proxies the media stream between endpoints rather than choosing DSP mode and uses SRTP media encryption).

Specifies whether or not to use media transcoding.

Media Transcoding requires a specific Transcoding License (Enhanced Media Sessions with Transcoding). Do not enable Media Transcoding unless your calling configuration requires it and SBC Edge is licensed for the Transcoding feature.

Specifies the Media List to use for this call route. This drop down list is populated with the Media List entries created through the Create Media list option. See Creating and Modifying Media Lists.

If the Media List configuration selected, then the Destination Signaling Group would be selected that has the common media set available. The media order from the call route's media list takes precedence over the Signaling Group's media list. Generally this field should be kept the default value "None" unless the media codec selection has to be controlled and manipulated for this route.

Specifies the number of calls over which the quality metrics are calculated.

Specifies the period of time in minutes after which a route is tried again after failing quality metrics.

Specifies the minimum answer/seizure ratio for this rule to be considered for use.

This field enables the Min. MOS score feature (call routes checked for voice quality) to be used. Valid entries: Enabled (enables the Min. MOS Score feature) or Disabled (disables Min. MOS Score feature)

The Min. MOS score provides an option to allow the SBC to temporarily enable/disable a route that is having bad voice quality.

Two options are available:

Enabled. A MOS score for quality purposes is added to each call using that specific route. The Quality Metrics Number of Calls field is used to determine the average acceptable value; if the average of acceptable calls falls below, it is considered bad voice quality and the route is then temporarily disabled for calls. The Quality Metrics Time Before Retry field is used when the route is disabled for failing metrics to determine how long before the route is retried.

Disabled. Min. MOS Score feature is disabled and all call routes are enabled.

Specifies whether or not to use Round Trip Delay.

Specifies the maximum average round trip (R/T) delay for this rule to be considered for use.

Specifies whether or not Jitter will be considered as a quality metric for this Call Route.

Specifies the maximum average jitter for this rule to be considered for use.