Ravi, A Capitalist

For personal use, gmail is great. But when it comes to commercial use, when you receive 10s and 100s of mails every second to various mail boxes in your domain name? You cannot trust google apps with that. What would happen to your mails if they suspend your account. And even if they wouldn’t it is always advisable to go for your own mail server when you have huge volumes of mails being transacted, and have so many different ids on just one domain, and if you would like your mails to be private than at someone elses mercy.

A mail server can be any web server that is colocated at any datacentre, installed with mail boxes and a mail server software. A mailserver doesnt usually come with apache and other web publishing or FTP provisions installed on it, as these would affect the performance of the mails.

A regular Pentium 4 Mail server can be used to handle over 500000 mails per hour, while, an optreon or a core 2 quad server can send upto 10 million in an hour, and process the same amount in receiving as well.

This kind of mail servers are for large companies that send out mails to several people outside their company, such as news letters or personalized stuff to various people.

A medium level software development company, having around 2000 employees need 2000 induvidual ids for the staff, and about another 1000 business ids, and let ssay every id sends out a mail every 2 mins, that is about 9000 mails every hour, and apart from the resources that you need to send out this many mails, you need to filter out the bounce mails, spam mails and forward the incoming mails to the appropriate mail boxes.

For all these, a Pentium 4 server should do great, provided it is not installed with anything other than the mail server software.