Sippax is audio video softphone software. Sippax is communication application based on SIP protocol for calling PC to PC, PC to Phone with or without registration to a voip provider. Sippax support audio codec G.729, G.723.1, GSM, G711 and vido codec H.263, H.261. Sippax can provide custom sofphone dialer for voip provider with private label, custom skin. Support free G.729 plugin codec.