Port 25 Options of Sendmail Server

[dbhasin at hss.hns.com]

Hi All,

Can somebody explain me the Port 25 options of SENDMAIL,
say u telnet at port 25,

telnet server 25

u can see plenty of options like HELO and EHLO, what all these commands actually
mean like when to use helo and what to mention say domain name or machine name?

Thanks
Deepak

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