I have attached the Edgemarc 250W Hardware Installation Guide.
However, this document will probably not have the information that you want because AT&T does not want customers to have access to such things as the VoIP configuration. If you are going to use this router on the AT&T U-verse network, they will setup the VoIP for their U-verse Voice service.
You could try to contact Edgewater Networks directly, but I doubt they will supply that information either due to NDAs with AT&T.
710755_1_Edg···uide.pdf
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