At SpaceWWW, we find it interesting to explain how sending and receiving e-mail through our company’s servers works.
First of all, we would like to clarify some basic concepts about sending and receiving e-mails:
- Sending and receiving email are independent processes.
- Email servers do not modify the information in an email or any attached files it may contain.
- Sending or receiving an email always involves multiple email servers, at least two: the sender’s and the recipient’s.
Email sending
We refer to “email sending” as the emails that are sent from the SpaceWWW servers.
The process of sending an e-mail is as follows:
Sender >> SpaceWWW Server >> (Internet) >> Destination Server >> Recipient
Normally, emails are composed using a ‘client’ program, such as Microsoft Outlook, our webmail program, or any other email program. These programs encode the text and attachments to be sent and then send it to our server, which collects it, identifies the destination server of the message and, immediately, forwards it to that server for delivery to the recipient.
Email delivery is always instantaneous. As soon as your email program processes the email, our servers send it to the recipient without delay.
If the destination server is busy or unavailable at the time our server sends the message, the delivery will be retried within the next few minutes.
If the message has not been delivered after 2 hours, our server will notify the sender that the email could not be delivered. If the sender does not receive a notification, it means that the email was delivered to the destination server. This may not mean that the destination server delivered it to the final recipient, as it may have been filtered as spam, a virus, the destination account may not exist, etc.
The most common reasons why a message cannot be delivered are that the destination server is technically unavailable (in which case the recipient should be contacted), or that the email address does not exist or is incorrect.
Outgoing messages do not pass through any filters, neither antivirus nor antispam. They have a maximum size limit (including attachments) of 75 MB and 50 recipients in copy.
Email reception
We refer to “email reception” as the emails sent from external servers to the SpaceWWW servers.
The process of receiving an e-mail is as follows
Sender >> External Server >> (Internet) >> SpaceWWW Server >> Recipient
Normally, emails are prepared using an email ‘client’ program, such as Microsoft Outlook or any other email program. These programs encode the text and attachments to be sent and then send them to the external server responsible for sending, which collects them, determines the destination server of the message and immediately forwards them to our server so that they can be delivered to the recipient.
Receiving email is a more complex process than sending it, as spam and virus messages are filtered out. In addition, we have a redundant system of multiple servers to ensure that all incoming email is delivered.
When a message is received, it goes to one of our mail servers. If that server has problems, one of the other servers will receive the message. This way we can ensure that all incoming messages are delivered.
Mail passes through two types of analysis: anti-spam and anti-virus.
Spam messages are discarded mainly for the following reasons:
- Spam senders do not comply with the basic rules for email senders.
- They usually use non-professional connections, which are detected and automatically discarded.
- There are certain email characters that are automatically identified as spam.
Therefore, the system ensures the correct receipt of all messages sent from professional servers and conforming to the Simple Mail Transfer Protocol.
It is not allowed to receive messages that contain attachments with the extensions .exe, .com, .bat, .vbs and .pif, as they are potentially dangerous if executed directly. If you wish to receive a message of this type, we recommend that you compress it into a zip or rar file.
We also have a new anti-virus system that scans all incoming messages smaller than 10 MB and compares them to over 500,000 known viruses.
If our system filters a message, a notification is always sent to the server that sent the message, and the sender should receive a confirmation of non-delivery.
El sistema anti-spam y anti-virus garantizan un filtrado del 90% de los mensajes. Siempre existen correos que no se pueden filtrar, pero por lo que si apostamos es por la fiabilidad del sistema de recepción de correos.