Inbound Routes

Introduction

The Inbound Routes feature allows service providers to create routing rules based on the dialed (DID) number.

Setup

LATA

The LATA of the LRN of the called number. This must match the Called LRN LATA field in the SIP Messages page.

SPID

The porting-corrected OCN of the called number. This must match the Called LRN SPID field in the SIP Messages page.

Prefix

A route can be matched to a prefix for a dialed number, or the prefix field can be left blank for the route to apply to any calling number. For Inbound Routes, the prefix refers to the dialed number regardless of whether the number has been ported.

Route Destinations

Routes are created by configuring groups of destinations. A destination must be either an IP address or a hostname followed by an optional port and optional tags. A destination may also refer to a specific trunk ID to route through a specific trunk group. Users can configure destinations based on priority (primary, secondary, tertiary) in case of failover.

Within each destination priority level, users can list multiple possible destinations separated by a comma to evenly distribute traffic.

Destinations per Route

Users can configure the Destinations per Route number to control the route failover order. The Destinations per Route number tells ClearIP how many routes from each route destination priority level to return in the Contact header.

If the Destinations per Route is 1, then ClearIP returns one destination from the Primary Route Destinations, one destination from the Secondary Route Destinations, and one destination from the Tertiary Route Destinations. ClearIP returns 3 routes in the Contact header in the order described. The destination is selected randomly from the available route destinations in each destination priority level. For outbound routing, this means that after the first routing failure at the preferred provider, the route should failover to the backup provider.

If the Destinations per Route is 2, then ClearIP returns two destinations from the Primary Route Destinations, two destinations from the Secondary Route Destinations, and two destinations from the Tertiary Route Destinations. ClearIP returns 6 routes in the Contact header in the order described. For outbound routing, this means that after the first routing failure at the preferred provider, the route should failover to another destination at the preferred provider before trying the backup provider.

If the Destinations per Route value is equal to or greater than the number of destinations in any particular destination priority level, then all listed destinations for that destination priority level are returned in the Contact header.

Examples

Route inbound calls to specific switch

If ClearIP is integrated to receive inbound calls from an SBC (or proxy) and the SBC must send the call to one of many switches, then ClearIP can be used to return a SIP 302 to direct the SBC to route certain inbound calls to a specific switch.

In this example, one switch with IP address 1.1.1.1 provides service for 3 phone numbers, and another switch with IP address 2.2.2.2 provides service for 3 other phone numbers. An Inbound Route is created for each individual phone number to define the correct switch to which the SBC should route the call.

We did not restrict these routes to apply to the Inbound Service Provider that typically defines calls received from external carriers. The above example is intended to apply to both 1) calls that originate on a switch within your network and terminate on a different switch in your network without being sent to an external carrier and 2) calls that are received from trunks with your origination carriers.

How ClearIP processes calls in Inbound Routing

Exact order of priority of inbound routing rules