Alestra - SIP Trunk
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Alestra is part of AxtelCorp a leading Mexican telecommunications company,which offers Communications and Information Technology solutions for enterprises, government and residential markets. Alestra delivers the most innovative information technology solutions for multinationals, enterprises and small companies, value added services such as design and management of complex telecommunications projects and data centers.
Reference website: Alestra
Before configuring the SIP trunk it is required to go through the following checklist and make changes where necessary:
- NAT (when used) created to 3CX
- Firewall Checker passed
- Firewall SIP ALG checked and if present disabled
Further setup information can be found in our Academy: 3CX Academy Basic Course
Some providers gained support and compatibility with 3CX on a specific product version. It is advisable to always run the latest version of 3CX to ensure ongoing compatibility.
Minimum 3CX Version: 3CX Phone System 15.5 SP2
Below is a short overview of the provider's capabilities and services and whether they’re supported or not:
- CLNS (Clip No Screening): No
- Catch All Routing: Yes
- Fax T.38 support: No
- CLIR (Number Suppression): No
- DTMF via RFC 2833: Yes
- Codec Order: G711A, G729
- NAT Support: Yes
- SRTP - No
Configuring the Trunk with 3CX
The general instructions outlining how to add a new SIP Trunk to your 3CX installation can be found here.
Adding the Trunk
Go to “SIP Trunks” and select “Add SIP Trunk”
- Select Country: MX
- Select Provider in your Country: Alestra
- Main trunk number: This will have been provided to you by Alestra. You must enter the number in the National number format (e.g. 5541638967)
- Press OK
Under the “General” tab in the “Trunk Details” enter the Outbound Proxy as provided to you by Alestra.
After, scroll down to the “Authentication” section and enter your:
- Main number in the “Authentication ID” field.
- Password in the “Authentication Password” field.
- Username in the “3 Way Authentication Password” field.
Once you have filled in these fields as given to you by Alestra, scroll to the top of the page and press OK. At this point if you refresh the page you should see your Alestra Trunk appear as Registered.
Adding Additional DIDs
To associate all other DIDs/Numbers you have in your Alestra account with 3CX, go to the Management Console → SIP Trunks, double-click on your Alestra Trunk and go to the “DIDs” tab.
Here you should already see 1 entry; that is the Main Trunk number you have set. Add all other DIDs/Numbers you have to the list in an National number format (e.g. 5541638967) and press OK.
Creating Inbound Rules
Now that you have associated all your DIDs/Numbers with your SIP Trunk in 3CX, you can create Inbound Rules to set where calls will be routed when those numbers are called. Instructions on how to create Inbound Rules can be found here.
When configuring Alestra SIP Trunks in 3CX, all numbers should be entered in an National number format (e.g. 5541638967), otherwise call routing may not work correctly.
Outbound Caller ID
Alestra Trunks do not support Clip No Screening which means you can’t present any number as your Outbound Caller ID. Only DIDs you have associated with your account can be presented as Caller ID when making outbound calls.
In order for this to work, any fields within 3CX that control the Outbound Caller ID must be populated in the National number format (e.g. 5541638967).
When configuring your Outbound Rules make sure that all numbers are dialed either in the National or International number formats. More information about how to create Outbound Rules and how they work can be found here.