DNS Records主要種別。A (IPv4)・AAAA (IPv6)・CNAME (Alias)・ALIAS/ANAME (Apex Alias)・MX (Mail)・TXT (DKIM/SPF/DMARC等)・SPF v=spf1 a mx ~all・DKIM (Cryptographic Email Signing)・DMARC v=DMARC1 p=reject/quarantine・MTA-STS・TLS-RPT・BIMI Brand Indicator・CAA (Certificate Authority Auth)・DS/DNSKEY (DNSSEC)・SRV (Service)、2026年DMARC強制化Gmail/Yahoo。