• Over the Internet, a message will often pass through several mail transfer agents to reach the recipients. Each of these has to store the message before forwarding it on and many, therefore, need to impose size limits.
• The result is that while large attachments may internally send within an organization, they are unreliable when sending across the Internet.
• e.g. In general, 10 MB is considered safe for the maximum size of an E-mail but, Google’* Gmail service increased its limit to 25 MB.
