OPTICAL NETWORK / 00
Follow the packet from the domain to the inbox.
A website and business email depend on several connected systems. These sheets show where the packet travels, which record answers and where a failure can interrupt the path.
01
Domain and DNS
The registration identifies control of the name. DNS points that name to the web and mail systems that should answer.
02
Website and certificate
The server returns the site while the certificate proves the encrypted connection belongs to the requested hostname.
03
Mail authentication
MX chooses the receiving server. SPF, DKIM and DMARC help receivers judge whether outgoing mail is authorised and aligned.
04
Backups and incidents
A restorable copy, known owners and a written response path matter when a domain expires, a certificate fails or a site is compromised.