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Internet
TCP/IP connection is two-way communication.
How do I broadcast email through a firewall? - Page 1
A router or gateway are hardware devices
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Sending email through a firewall requires the firewall to be setup to allow email messages a free path to travel. Internet TCP/IP connection is two-way communication. You will be sending information to the mail server and it will be sending status information back and two ports will be involved in the conversation: the client's port and the server's port. (Transmission Control Protocol Internet Protocol is the primary protocol used on the Internet). Protocol a method of sending and receiving data. All ports below 1025 are reserved for use by specific protocols. Port 25 is reserved for SMTP mail servers, port 110 for POP3 mail servers and port 143 for IMAP4 mail servers. Since the client is not a mail server - it can't use port 25 therefore, the client system will auto select a port above 1024 and the mail server will communicate on ports 25, 110 and 143. Your firewall will have to allow outbound traffic from any internal port greater than 1024 to external ports 25, 110 and 143. Your firewall will also need to allow inbound traffic from external ports 25, 110 and 143 to any internal port greater than 1024. Your default server port can be changed by specifying the desired port number in the MailPort property for SMTP or POP3 and IMAP4, plus adjusting the mail server to listen on those ports (client port can't be changed).
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I am unable to
broadcast any emails?
If your PCs modem is directly
connected to the Internet
and you can't broadcast any emails...
Mail Server IP Address
Nslookup Example - if your domain is mailsbroadcast.com enter; Nslookup mailsbroadcast.com [hit enter
key] to display
your domain IP address. More info about
nslookup <><><><><><><>
NAT - Network Address Translation, allows a router (which represent an entire local area network to the Internet) to act as a single IP address. And all traffic leaving a LAN (Local Area Network) will be as if it originated from a global IP address and all traffic coming into the LAN will also be using the same global IP address. Therefore, since a LAN cannot be seen from the outside (all workstation hidden from the Internet), registration of the internal IP addresses or Local IP Address (below) will not be necessary and the normal range of private addresses allocated are: 10.0.0.0 - 10.255.255.255 - 172.16.0.0 - 172.31.255.255 - 192.168.0.0 and 192.168.255.255 See Private Network NAT Therefore, any LAN workstation connected to the Internet needs an IP address, LAN router IP address, IP address name server and NAT subnet mask interface. And the LAN system must also set-up a service table of fixed IP address mappings that allows packets to originate from the outside.
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