An email router is an online service that simplifies and enriches (through statistics and tracking) the email marketingEmail marketing, also known as Emailing, is a digital marketing strategy that uses email as its medium. It is one of the... More process.
This type of service, much used and appreciated by companies that own their email lists, facilitates the way of sending large amount of promotional emails (known as bulk emails).
The main advantage of an email router is that it enables promotional emails to be sent without having to worry about technical configuration: the router already has all the technical infrastructure needed to send emails (SMTPSMTP stands for “Simple Mail Transfer Protocol”. Created in 1982, SMTP is an email transfer protocol used for... More server, IP addresses pool required for sending, etc.), which greatly simplifies the process of sending advertising emails for companies.
As the intermediary between the sender and the end-customer, the router is an important player of the emailing ecosystem, and must apply whole emailing best practices, because otherwise it may to be blocked by the various ESPs (gmail, outlook, etc.).
To achieve this, email routers set up metrics to measure in real time their own customers quality, in order to block as soon as possible those who do not respect emailing best practices.
The main metrics used by routers to judge the quality of the companies they work with include :
– hard bounceA hard bounce is an email marketing concept. It refers to a notification which indicates that a message sent has not bee... More rate (which should be less than 5% on most routers)
– complaint rate (which must be less than 0.5% on most routers)
– open and click rates (which must be high enough to show the interest of people who receive the emails).
These metrics are collected during each email campaign, but also globally for all campaigns on the customer’s account, to average them out and evaluate their evolution.
On a daily basis, customers add new email lists (in their router user account) that have not been used recently, resulting in a hard bounce rate that is too high, and causing the router to block customer’s account. At this moment, the only solution to unlock the situation is to use the professional services of a tool such as an email verifierAn email verifier, also known as an email checker, is a software used to check an email address or a list of email addre... More, in order to clean up the list of invalid contacts, and enable the customer to reuse the email router’s services.
Routers allow their customers to operate in two distinct modes: shared mode and dedicated mode.
In shared mode (which is used by the majority of customers), router clients pass through shared IP pools, i.e. the IP addresses used to send emails are shared. This technical element has the advantage of ensuring a constant flow of emails, and therefore of keeping the IP address “warm” (which is an important element in ensuring its proper functioning).
The main disadvantage of this mode is that the shared aspect can sometimes reduce the deliverability of emails from a given client: as the reputation of the IP address is shared by all clients, if some of them send low-value emails, then the ESPs (gmail, outlook, yahoo, etc.) can degrade the reputation of this specific IP, and this will also have the effect of degrading the deliveries of the router’s other clients (who will suffer this degradation without being the cause of it).
To avoid this possible negative and unpredictable effect of other customers, email routers offer to their customers (with have sufficient sending volume) the possibility of using a dedicated IP solution. In this mode, the reputation of the sending IP is no longer shared with other customers, which prevents it from being degraded by someone else.
It’s important to keep in mind, however, that the dedicated IP must send regular and progressive traffic (this is known as IP warm-up), otherwise it won’t deliver the expected deliverability results. This mode should therefore only be reserved for customers who send at least 200,000 emails a month, and who send on a very regular basis, otherwise it will be less efficient than shared IP and cost more to the customer.
The router’s own reputation is an important factor to consider when it comes to the effectiveness of your email campaigns: some routers are known to offer a good quality and deliver easily to the inbox, while others are of poorer quality and will almost systematically result in emails being delivered to the spam box. It’s therefore important to be cautious when choosing your email routing solution, and to opt for a serious actor in this field (for example: mailjet, etarget or mailchimp).