ANALISIS DAN SIMULASI LAYANAN VPN IP PADA JARINGAN METRO ETHERNET BERBASIS VLAN DI PT. TELKOM Tbk (Divisi Infratel) ANALYSIS AND SIMULATION SERVICES IP VPN IN METRO ETHERNET BACKBONE NETWORK BASED ON VLAN IN PT TELKOM Tbk. (INFRATEL DIVISION) - INDRA JATI (Universitas Telkom, 2010)