To provide the answers, we asked our delivery expert, Sean Swanepoel who advised us ….. ‘The speed of our sending is dictated by how fast the recipient server can accept . Because of these limitations, caused by network issues, full mailboxes and invalid addresses, there is a strain created by retrying. Without those, delivery would be almost ‘light speed’! ‘
As Shawn highlights and as we have stated in past blog articles emails go through many steps to reach their target consequently affecting the delivery time of your campaign and here we list a few of them :
• How busy the ISP (Internet Service Provider) is
• How fast the recipient email server is able to accept it
• The anti-spam techniques employed by the recipient server to block SPAM from getting through to the recipient.
As with all other services, ISPs have their peak periods and slow periods and it is at the really busy periods that email sends are likely to be delayed. It may be useful to keep this in mind when planning your sends.
How fast the recipient Server can accept the incoming email
Every email is dispatched from the sending server to the recipient server. It is not, however simply a matter of getting from one end to the other. With Spam being everyone’s major annoyance, ISPs are being ultra-serious in their attempts to ensure that their users don’t receive hundreds and thousands of SPAM messages to their in boxes, so they set up certain rules that every email must go through in order to be delivered to the inboxes of that particular ISP’s clients. The settings can vary widely from each ISP although they will all usually include a limit on the number of recipients for each message or connection, or a rate limit, such as a limit on the number of messages permitted to be sent out over a certain period of time. This is their outline of how many emails they are willing to accept over a given period.
If your sends do not comply with these specifications, your emails are more likely to bounce. This is not a big worry however, because bulk email service providers call upon the assistance of Mail Transfer Agents (MTAs) whose task it is to arrange their sends according to the various specific limitations of each individual ISP, thus ensuring that their sends are in compliance with these regulations.
Anti-spamming techniques
ISPs apply a wide range of anti-spamming techniques as a strategy to combat spam. (Sean suggests that you read more about them here). A common example of this is Grey Listing; This is when emails are required to retry over a specific period of time before they will be accepted by the ISP. This is a really efficient anti-spamming device, as spammers do not generally retry sending their messages. However, it does have an impact on you, as your legitimate bulk emails also have to undergo this process before they can be delivered.
So there you have it - predicting an exact delivery time is a highly technical ‘piece of string’ – and, as there are so many factors involved, nearly as impossible to estimate. However, As members of ReturnPath, the EEC and Truste, GraphicMail does try to ensure timely delivery. To find out more about deliverability issues, read this blog article or watch our video.
