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Internet Service Provider (ISP)

Company that provides internet services, and most often, other associated services, such as email. That's why they include anti-spam filters, maintain blacklists, and can block senders if they believe they are conducting fraudulent email campaigns.

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How to identify your ISP?

Your Internet Service Provider (ISP) is your access provider to the internet. In Spain, ISPs like Movistar, Vodafone or Orange operate. You can confirm this on the website, where you can also find the IP that identifies your connection. Besides those providing internet access, there are other types of ISPs, such as virtual operators that contract connections from major ISPs for resale, domain registrars, or cloud server providers.

How does the ISP establish an internet connection?

The ISP provides its customer with a modem or router (the device that encodes and decodes data, enabling its transmission) to access the internet, along with a username, password, and a phone number for establishing the connection. When the user connects or dials in, the ISP verifies their data, assigns an IP address for identification, and grants access to connect to the servers hosting web pages or handling email. This is made possible by the TCP/IP protocols that allow communication between computers to send and receive information, and the HTTP/HTTPS protocol that browsers interpret to display web pages on the user's screen. ISPs are aware of the websites visited and the number of messages sent from each IP because they manage access to this information, even though it's done privately and on a massive scale for their millions of customers.

How does the ISP impact email marketing?

Internet Service Providers implement filters to ensure a quality service for their customers and protect them from unwanted email. They achieve this by affecting the deliverability of email campaigns in several ways, such as maintaining blacklists. ISPs monitor which IP addresses send more messages identified as spam and may block those senders to cut off their distribution channel. ISPs may also raise concerns and consider the use of their service as fraudulent in certain situations. This includes sudden spikes in email volume instead of consistent sending, user behaviour indicating messages are consistently deleted without being read, or when too many emails are sent to inactive accounts. In these cases, ISPs may view these as unsupervised mass email campaigns and may block them.