Provider SignalWire (US)

https://signalwire.com/blogs/product/programmable-sip-connectivity-and-routing

Inbound and outbound works globally. Config files also available at: https://www.twilio.com/docs/sip-trunking/sample-configuration#freeswitch.

Add the SignalWire IP addresses into the domain section under autoload_configs/acl.conf.xml you can nslookup sip.signalwire.com

<configuration name="acl.conf" description="Network Lists">
    

Registration: /usr/local/freeswitch/conf/sip_profiles/external/

<include>
        <gateway name="signalwire-outbound">
                <param name="username" value="---user---"/>
                <param name="password" value="---password---" />
                <param name="proxy" value="example.signalwire.com" />
                <param name="register" value="false"/>
        </gateway>
      <gateway name="signalwire-inbound">
      <param name="username" value="---user---"/>
      <param name="password" value="---password---"/>
      <param name="proxy" value="example.signalwire.com"/>
      <param name="register" value="false"/>
      <param name="dtmf-type" value="rfc2833"/>
      <param name="context" value="public"/>
      </gateway>
</include>

Inbound calling: /usr/local/freeswitch/conf/dialplan/public/

<include>
  <extension name="public_did">
    <condition field="destination_number" expression="^\+15550000000$">
      <action application="set" data="domain_name=$${domain}"/>
      <action application="playback" data="phrase:greeting"/>
      <action application="transfer" data="1000 XML default"/>
    </condition>
  </extension>
</include>

Outbound calling: /usr/local/freeswitch/conf/dialplan/default/

<include>
   <extension name="twilio-outbound">
    <condition field="destination_number" expression="^(1{0,1}\d{10})$">
    <action application="set" data="effective_caller_id_number=+15550000000"/>
    <action application="set" data="effective_caller_id_name=${outbound_caller_id_name}"/>
    <action application="bridge" data="sofia/gateway/signalwire-outbound/+1$1"/>
  </condition>
   </extension>
</include>

Send any SMS from Dialplan to your smartphone, notifying you of various things that happening.

    <extension name="signalwire sms curl">
      <condition field="destination_number" expression="^767$">

        <!-- setup bleg uuid of this call so we we know it before hand -->
        <action application="set" inline="true" data="bleg_uuid=${create_uuid()}"/>

        <!-- setup signalwire credentials -->
        <action application="set" inline="true" data="space_name=XXXXXX"/>
        <action application="set" inline="true" data="project_key=XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"/>
        <action application="set" inline="true" data="api_token=PTXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"/>

        <!-- not using '+' here, just the 11 digit number itself, see curl line below -->
        <action application="set" inline="true" data="signalwire_number=18005551212"/>
        <action application="set" inline="true" data="cellphone=18885559999"/>

        <!-- urlencode your 'spaces' to '%20' so the text body will work in the url, may need to consider other untested punctuation -->
        <action application="set" inline="true" data="sms_body=${system(printf 'aleg ${uuid} is calling bleg ${bleg_uuid}' | sed -r 's/ /%20/g')}"/>

        <!-- We need to base64 encode the basic authorization for curl request-->
        <action application="set" inline="true" data="auth=${system(printf '${project_key}:${api_token}' | base64 --wrap 0)}"/>

        <!-- notice for E.164 formatting we encode the '+' to '%2B' for the 'From' and 'To' params on the URL, and must send as post -->
        <action application="curl" data="https://${space_name}.signalwire.com/api/laml/2010-04-01/Accounts/${project_key}/Messages.json?From=%2B${signalwire_number}&To=%2B${cellphone}&Body=${sms_body} append_headers Authorization:'basic ${auth}' post"/>

        <action application="answer"/>
        <action application="bridge" data="{origination_uuid=${bleg_uuid}}user/1004"/>
      </condition>
    </extension>

For a more comprehensive walk through of provisioning SignalWire trunks, configuring FreeSWITCH, and best practices please see our signalwire.com docs https://signalwire.com/blogs/product/programmable-sip-connectivity-and-routing.