From your fax application view point it s a fax modem pool. From IP network view point it s a H.323 endpoint with T.38 fax support. From your view point it s a gateway between a fax application and IP network.

T38FAX Pseudo Modem From your fax or voice application view point it s a fax/voice modem pool. From IP network view point it s a H.323 endpoint with T.38 fax support. From your view point it s a gateway between an application and IP network.