Outbound Routes

The Outbound Routes feature allows service providers to create routing rules based on the LRN of the called number. Outbound Routes can be applied based on the prefix of the dialed number if the number has not been ported. If the dialed number has been ported, then the Outbound Route prefix field must refer to the LRN of the dialed number.

The Outbound Routes table is searched after the Inbound Routes table.

Setup

Jurisdiction

Outbound routes can be restricted to calls within a certain jurisdiction:

• International - No restriction. Choosing this allows the route to apply to all calls to include this jurisdiction and all lower jurisdictions.
• Domestic - Route only applies to calls where the calling number and called number are based in same country.
• Intrastate - Route only applies to calls where the calling number and called number are based in same US state or Canadian territory.
• Local - Can be configured to be defined as Intra LATA or Intra Rate Center in the SBCs page.

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

If the dialed number has been ported, then the Outbound Route prefix field must refer to the LRN of the dialed number. If the number has not been ported, then this field can apply to the prefix of the dialed number.

In the SIP Messages page, you can check the Ported Called Number column to determine whether a number has been ported. If the Ported Called Number field is set to Yes, then the Called LRN NPANXX column shows the NPANXX of the ported number LRN. For a ported number, you should use the Called LRN NPANXX value to enter into the Outbound Route Prefix field. The Outbound Route rule applies to all numbers associate with that LRN NPANXX and not just the individual phone number.

If the Ported Called Number is set to No, then you can use the Translated Called Number value to enter into the Outbound Route Prefix field.

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. For outbound routing, the Primary Route Destinations may be destinations belonging to a preferred provider while the Secondary Route Destinations may be destinations belonging to a backup provider.

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

Route Prefix

For each destination priority level, users may configure a prefix to be added in front of the phone number in the Contact header. This can be useful if different phone number prefixes are required by different providers. Entering a prefix of abc would enable ClearIP to prepend this value in the SIP 302 Contact header phone number.

SIP/2.0 302 Moved Temporarily
Via: SIP/2.0/TLS sip.clearip.com:5061;branch=z9hG4bK8344.f8e5f5ab71c17a71a8fb7fa51bba8d45.0;i=df8b5cb1;received=::ffff:10.0.14.85
Via: SIP/2.0/TCP 192.168.1.89:3000;received=18.208.235.205;branch=z9hG4bK-4434-1-0
To:  <sip:14045266060@1.2.3.4:5060>;tag=5a714413-87d9-4082-8317-f7ade000768e
From:  <sip:14047884802@192.168.1.89:3000>;tag=1
Call-ID: 1-4434@192.168.1.89
CSeq: 1 INVITE
Contact: <sip:abc14045266060@1.0.0.3>;q=0.99
Reason: SIP;cause=302;text="no-fraud-detected"
Content-Length: 0

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 toll-free calls through preferred provider

ClearIP can be used to route all outbound toll-free calls through a preferred provider. For each 8YY area code, you can create an Outbound Route with the destinations set for the preferred provider. The route must be restricted to apply to outbound calls only.

Route calls to an LRN to an ordered list of IP addresses

ClearIP can be used to route calls to a static, ordered list of destination IP addresses.

The number 14045266060 has been ported which can be confirmed in the SIP Messages page under the Ported Called Number field, and the Called LRN NPANXX gives us the NPANXX of the LRN to which the number has been ported.

We can create an Outbound Route that applies to either the Called LRN NPANXX or the Called LRN field by entering the same value into the Prefix field of the Outbound Route. This Outbound Route is configured to direct the SBC to send the call first to a preferred destination with IP address 1.1.1.1. If that destination is not available, then the SBC should try to send the call to the next destination 2.2.2.2. If that is not available, then the SBC would try to send the call to the next destination 3.3.3.3.

This Outbound Route applies to all calls to called numbers that have been ported to an LRN with the same NPANXX. If you would like to create a static route that only applies to a single phone number that has been ported and not the entire LRN, then you should create a route in the Inbound Routes page instead.

This Outbound Route returns the following SIP 302 response:

SIP/2.0 302 Moved Temporarily
Via: SIP/2.0/TLS sip.clearip.com:5061;branch=z9hG4bKf144.11a0effe8b009ef5ec9b6a1d431a26ba.0;i=c2f143d4;received=::ffff:10.0.11.136
Via: SIP/2.0/TCP 192.168.1.89:3000;received=18.208.235.205;branch=z9hG4bK-4199-1-0
To:  <sip:14045266060@1.2.3.4:5060>;tag=2da74072-aef4-40fb-99b8-e89e173f209f
From:  <sip:14047884802@192.168.1.89:3000>;tag=1
Call-ID: 1-4199@192.168.1.89
CSeq: 1 INVITE
Contact: <sip:14045266060@1.1.1.1>;q=0.99, <sip:14045266060@2.2.2.2>;q=0.98, <sip:14045266060@3.3.3.3>;q=0.97
Reason: SIP;cause=302;text="no-fraud-detected"
Content-Length: 0

Route calls to an LRN to load balance between IP addresses

In this Outbound Route, there is a comma separated list without spaces of 3 IP addresses entered in the Primary Route Destinations field with Destinations Per Route set to 3.

ClearIP returns a SIP 302 response with a list of all 3 IP addresses listed in a random order with the order varying for each SIP 302 response.

SIP/2.0 302 Moved Temporarily
Via: SIP/2.0/TLS sip.clearip.com:5061;branch=z9hG4bK8344.f8e5f5ab71c17a71a8fb7fa51bba8d45.0;i=df8b5cb1;received=::ffff:10.0.14.85
Via: SIP/2.0/TCP 192.168.1.89:3000;received=18.208.235.205;branch=z9hG4bK-4434-1-0
To:  <sip:14045266060@1.2.3.4:5060>;tag=5a714413-87d9-4082-8317-f7ade000768e
From:  <sip:14047884802@192.168.1.89:3000>;tag=1
Call-ID: 1-4434@192.168.1.89
CSeq: 1 INVITE
Contact: <sip:14045266060@1.0.0.3>;q=0.99, <sip:14045266060@1.0.0.1>;q=0.98, <sip:14045266060@1.0.0.2>;q=0.97
Reason: SIP;cause=302;text="no-fraud-detected"
Content-Length: 0

How ClearIP processes calls in Outbound Routing

Exact order of priority of outbound routing rules