2.1.3 Network DevicesYou must evaluate the network devices that are used in the existing network to see if a VoIP network can beimplemented. Below are the points that should be evaluated.Can the firewall pass packets appropriately?If the VoIP network contains a firewall, the firewall must be configured appropriately to allow VoIP packets,listed in the table below, to pass through the network without being blocked by filtering.For more information, consult your network administrator.[IP Packets from IPCMPR/IPCEMPR/IP-EXT16 Card and IP Telephones]Protocol Description TCP/UDP Default Port No.RTP (IP telephoneconnected to IPCMPR/IPCEMPR)Real-time Transport Protocol.Used for voice data transmission.UDP 12000 to 12255RTP (IP-PT connected toIP-EXT16)UDP 8000 to 8063Maintenance (IPCMPR/IPCEMPR)Panasonic proprietary protocol.Used for communication parameternegotiation with the PBX, download ofcountry/area data, confirmation ofconnection with the PBX, andnotification of error messages andstatistical information to the PBX.TCP 35300Maintenance (IP-EXT16) UDP 9300Maintenance (IPtelephone)UDP 9301MGCP (IPCMPR/IPCEMPR/IP-EXT16)Media Gateway Control Protocol.Used for call control command data andLCD/LED data transmission.UDP 2727MGCP (IP telephone) UDP 2427DHCP (IPCMPR/IPCEMPR)Dynamic Host Configuration Protocol.Used for receiving an IP address from aDHCP server.UDP 67, 68DHCP (IP telephone) UDP 67, 68FTP (Port mode) File Transfer Protocol.Used for receiving a data file from a FTPserver to upgrade the firmware version.TCP 20, 21SNTP (IPCMPR/IPCEMPR)Simple Network Time Protocol.Used for clock synchronisation.UDP 123SNMP (IPCMPR/IPCEMPR)Simple Network Management Protocol.Used for monitoring network-attacheddevices.UDP 161[IP Packets from V-IPGW16 Card]Protocol TCP/UDP Default Port No.RTP/RTCP UDP 12000 to 12255H.245 TCP 10000 to 10447H.225.0 Call Signalling TCP 1720IP Networking Guide 212.1.3 Network Devices