Configurar LAN y VPN para llamadas Wi-Fi de AT&T

Allow Internet Protocol Security (IPSec)
Internet Protocol Security is a method of encrypting traffic sent through the internet. It's used to provide a secure voice and data communication path. Algunos enrutadores permiten bloquear mensajes de IPSec. Las llamadas Wi-Fi de AT&T requieren que se habilite el paso de mensajes IPSec.

Open data ports 500, 4500, and 143
Ports 500, 4500, and 143 (shown in the table) are used to communicate to the AT&T network and must be set to open.

Puertos de datos

Puerto	TCP o UDP	Nombre del servicio o protocolo	RFC	Nombre del servicio
500	UDP	Llamadas a través de Wi-Fi	5996	IKEv2
4500	UDP	Llamadas a través de Wi-Fi	5996	IKEv2
143	TCP	Internet Message Access Protocol (IMAP)	3501	imap

Set Maximum Transmission Unit (MTU) to 1500
MTU represents the maximum packet size that can be transmitted. Wi-Fi Calling performs best if the MTU is set to 1500.

Update equipment firmware
For best performance, always update modems, routers, and switches to the latest software/firmware versions available. Updates can typically be found on the equipment manufacturer's website

Nombre de dominio completamente calificados para llamadas Wi-Fi (FQDN)
A fully qualified domain name (FQDN) is the domain name for a computer, or other host equipment on the internet. Las llamadas Wi-Fi deben poder atravesar los siguientes FQDN:

• epdg.epc.att.net
• sentitlement2.mobile.att.net
• vvm.mobile.att.net