speakerdeck.com

Checked 22 October 2026, 10:46 UTC · via 8.8.8.8
!Passed with warnings
24 passed 2 warnings 0 failed 5 info

Registration

info

.com generic · 1API GmbH · expires 2027-05-12

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
1API GmbH
Registered
12 May 2010
Last changed
7 May 2026
Expires
12 May 2027
Status
client transfer prohibited
Registry nameservers
john.ns.cloudflare.com, nola.ns.cloudflare.com
RDAP server
https://rdap.verisign.com/com/v1/

Checks

  • i
    .com is a generic TLD (gTLD)
    Generic TLD under an ICANN registry agreement: ICANN-accredited registrars, UDRP and RDAP apply.
    #1
  • ✓ TLD delegated and signed #2
    .com is delegated in the root zone and DNSSEC-signed.
  • ✓ Expires on 2027-05-12 #3
    The registration is valid until 2027-05-12 (202 days).
  • ✓ Transfer locked #4
    Registry status: client transfer prohibited.
  • ✓ Registry and delegation match #5
    The nameservers registered at the registry are the ones published in DNS.

Delegation

info

john.ns.cloudflare.com, nola.ns.cloudflare.com

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
john.ns.cloudflare.com, nola.ns.cloudflare.com
NS in the zone
john.ns.cloudflare.com, nola.ns.cloudflare.com
NameserverAddressesNetwork (AS)Glue
john.ns.cloudflare.com173.245.59.185 108.162.193.185 172.64.33.185 2606:4700:58::adf5:3bb9 2803:f800:50::6ca2:c1b9 2a06:98c1:50::ac40:21b9AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US108.162.193.185 172.64.33.185 173.245.59.185 2606:4700:58::adf5:3bb9 2803:f800:50::6ca2:c1b9 2a06:98c1:50::ac40:21b9
nola.ns.cloudflare.com108.162.192.212 172.64.32.212 173.245.58.212 2a06:98c1:50::ac40:20d4 2606:4700:50::adf5:3ad4 2803:f800:50::6ca2:c0d4AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US108.162.192.212 172.64.32.212 173.245.58.212 2606:4700:50::adf5:3ad4 2803:f800:50::6ca2:c0d4 2a06:98c1:50::ac40:20d4

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: john.ns.cloudflare.com, nola.ns.cloudflare.com.
    #6
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • ✓ No glue needed #8
    All nameservers are outside the zone, so no glue records are needed.
  • ✓ All names resolve #9
    Every nameserver name has an address and is not an alias.
  • ✓ Nameservers in different networks #10
    The nameservers are spread over 6 IPv4 /24s and 4 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS13335 (CLOUDFLARENET - Cloudflare, Inc., US): 12 addresses). An outage or attack on that network affects all nameservers; large anycast providers mitigate this, but a secondary DNS provider adds independence.
    #11
  • i
    All nameserver names under .com
    All nameserver names are under one TLD, so a problem with that TLD also makes the nameservers unreachable. Some operators use names under two TLDs for extra resilience.
    #12
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

warn

12 of 12 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
john.ns.cloudflare.com 173.245.59.185NOERROR, 5 ms, authoritativenoyes / yesrefused2026.10.2
john.ns.cloudflare.com 108.162.193.185NOERROR, 5 ms, authoritativenoyes / yesrefused2026.10.2
john.ns.cloudflare.com 172.64.33.185NOERROR, 6 ms, authoritativenoyes / yesrefused2026.10.2
john.ns.cloudflare.com 2606:4700:58::adf5:3bb9NOERROR, 5 ms, authoritativenoyes / yesrefused2026.10.2
john.ns.cloudflare.com 2803:f800:50::6ca2:c1b9NOERROR, 5 ms, authoritativenoyes / yesrefused2026.10.2
john.ns.cloudflare.com 2a06:98c1:50::ac40:21b9NOERROR, 5 ms, authoritativenoyes / yesrefused2026.10.2
nola.ns.cloudflare.com 108.162.192.212NOERROR, 4 ms, authoritativenoyes / yesrefused2026.10.2
nola.ns.cloudflare.com 172.64.32.212NOERROR, 6 ms, authoritativenoyes / yesrefused2026.10.2
nola.ns.cloudflare.com 173.245.58.212NOERROR, 5 ms, authoritativenoyes / yesrefused2026.10.2
nola.ns.cloudflare.com 2a06:98c1:50::ac40:20d4NOERROR, 6 ms, authoritativenoyes / yesrefused2026.10.2
nola.ns.cloudflare.com 2606:4700:50::adf5:3ad4NOERROR, 5 ms, authoritativenoyes / yesrefused2026.10.2
nola.ns.cloudflare.com 2803:f800:50::6ca2:c0d4NOERROR, 5 ms, authoritativenoyes / yesrefused2026.10.2

Checks

  • ✓ All respond #14
    All 12 nameserver addresses answered.
  • ✓ All authoritative #15
    Every responding nameserver answers authoritatively for the zone.
  • ✓ No recursion #16
    The nameservers do not answer recursive queries for other domains.
  • !
    Software version disclosed
    These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: john.ns.cloudflare.com: "2026.10.2"; nola.ns.cloudflare.com: "2026.10.2". Hide or replace the version string.
    #17
  • ✓ Zone transfers refused #18
    No nameserver allows a zone transfer to the public.
  • ✓ TCP supported #19
    All nameservers answer over TCP.
  • ✓ EDNS supported #20
    All nameservers support EDNS(0).
  • ✓ Public addresses #21
    All nameserver addresses are publicly routable.

SOA

pass

serial 2416598553 · primary john.ns.cloudflare.com

Found

Primary (MNAME)
john.ns.cloudflare.com
Contact (RNAME)
dns.cloudflare.com
Serial
2416598553
Refresh / retry
10000 s / 2400 s
Expire
604800 s
Negative TTL
1800 s

Serial per nameserver

NameserverSerial
john.ns.cloudflare.com (173.245.59.185)2416598553
john.ns.cloudflare.com (108.162.193.185)2416598553
john.ns.cloudflare.com (172.64.33.185)2416598553
john.ns.cloudflare.com (2606:4700:58::adf5:3bb9)2416598553
john.ns.cloudflare.com (2803:f800:50::6ca2:c1b9)2416598553
john.ns.cloudflare.com (2a06:98c1:50::ac40:21b9)2416598553
nola.ns.cloudflare.com (108.162.192.212)2416598553
nola.ns.cloudflare.com (172.64.32.212)2416598553
nola.ns.cloudflare.com (173.245.58.212)2416598553
nola.ns.cloudflare.com (2a06:98c1:50::ac40:20d4)2416598553
nola.ns.cloudflare.com (2606:4700:50::adf5:3ad4)2416598553
nola.ns.cloudflare.com (2803:f800:50::6ca2:c0d4)2416598553

Checks

  • ✓ Serial 2416598553 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 2h46m40s, retry 40m, expire 7d, negative TTL 30m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver john.ns.cloudflare.com is one of the listed nameservers.
  • ✓ Contact dns@cloudflare.com #25
    The SOA RNAME dns.cloudflare.com means dns@cloudflare.com.
  • ✓ Timestamp serial #26
    The serial 2416598553 is a Unix timestamp (2046-07-30 21:22 UTC).

DNSSEC

warn

Not signed

Found

Validated by resolver
no

Checks

  • !
    Not signed
    The zone is not signed with DNSSEC, so answers can be spoofed. Enable DNSSEC at your DNS provider and publish the DS record at your registrar.
    #27

Records

info

18 records at the apex

Found

Read from
173.245.59.185:53
TypeValueTTL
SOAjohn.ns.cloudflare.com. dns.cloudflare.com. 2416598553 10000 2400 604800 18001800
NSjohn.ns.cloudflare.com.86400
NSnola.ns.cloudflare.com.86400
A172.66.158.156300
A104.20.28.181300
AAAA2606:4700:10::6814:1cb5300
AAAA2606:4700:10::ac42:9e9c300
MX1 aspmx.l.google.com.300
MX10 aspmx2.googlemail.com.300
MX10 aspmx3.googlemail.com.300
MX5 alt1.aspmx.l.google.com.300
MX5 alt2.aspmx.l.google.com.300
TXT"ALIAS for speakerdeck.com.herokudns.com"300
TXT"facebook-domain-verification=5rzw9hjdxxzobpi4p6lk9tlvpldfej"300
TXT"google-site-verification=3ggCXuHu3Wkywh0QJ4MVBy9jz0MMfAEVJGNVQP56eyY"300
TXT"google-site-verification=U0zznvYUS5x_csx7-HqM5TJh-EGrTvjQOR7wCPGyv74"300
TXT"stripe-verification=51e5bf1257eaab3496a4c15cdce19f2c27d591dd7d87097e936b1fbc2e84a855"300
TXT"v=spf1 include:mailgun.org include:userlist.com include:spf.auth.aws.groovehq.com ~all"300

Checks

  • ✓ TTLs within range #32
    TTLs: A 5m, AAAA 5m, MX 5m, NS 1d. The NS TTL at the parent is 2d and in the zone 1d; resolvers may use either.
  • ✓ No CNAME at the apex #33
    The zone apex has no CNAME record.
  • ✓ No wildcard #34
    Names that don't exist return NXDOMAIN.
  • i
    No CAA records
    Without CAA records any certificate authority may issue certificates for this domain. A CAA record limits issuance to the CAs you use.
    #35