Domain report: tudelft.nl

Registration

info

.nl country-code

Found

TLD: .nl (country-code)
ICANN policies apply: no

Lookup error: https://rdap.sidn.nl/domain/tudelft.nl returned HTTP 429

Checks

i

.nl is a country-code TLD (ccTLD)

Country-code TLD: governed by its local registry under national policy, not by an ICANN contract. Registrar accreditation, dispute resolution and RDAP/WHOIS rules are set by the registry.

#1
✓ TLD delegated and signed #2

.nl is delegated in the root zone and DNSSEC-signed.
i

Could not be checked

The RDAP lookup failed, so this could not be checked: https://rdap.sidn.nl/domain/tudelft.nl returned HTTP 429

#3

Delegation

info

ns1.surfnet.nl, ns1.tudelft.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns2.tudelft.nl

Found

Parent zone: nl
Delegation from: ns1.dns.nl (194.0.28.53)
NS at the parent: ns1.surfnet.nl, ns1.tudelft.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns2.tudelft.nl
NS in the zone: ns1.surfnet.nl, ns1.tudelft.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns2.tudelft.nl

Nameserver	Addresses	Network (AS)	Glue
ns1.surfnet.nl	192.87.106.101 2001:610:1:800a:192:87:106:101	AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL	192.87.106.101 2001:610:1:800a:192:87:106:101
ns1.tudelft.nl	130.161.180.1	AS1128 TUDELFT-NL - SURF B.V., NL	130.161.180.1
ns1.zurich.surf.net	195.176.255.9 2001:620:0:9::1103	AS559 Switch - SWITCH, CH AS559 Switch - SWITCH, CH	-
ns2.surfnet.nl	192.87.36.2 2001:610:3:200a:192:87:36:2	AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL	192.87.36.2 2001:610:3:200a:192:87:36:2
ns2.tudelft.nl	130.161.180.65	AS1128 TUDELFT-NL - SURF B.V., NL	130.161.180.65

Checks

✓ 5 nameservers #6

Delegated to ns1.surfnet.nl, ns1.tudelft.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns2.tudelft.nl.
✓ Parent and zone agree #7

The parent delegation and the zone's NS records list the same nameservers.
✓ Glue present and correct #8

Glue is published for the nameservers inside the zone: ns1.tudelft.nl, ns2.tudelft.nl.
✓ 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 4 IPv4 /24s and 3 IPv6 /48s.
✓ 3 autonomous systems #11

The nameservers are spread over: AS1103 (SURFNET-NL - SURF B.V., NL): 4 addresses; AS1128 (TUDELFT-NL - SURF B.V., NL): 2 addresses; AS559 (Switch - SWITCH, CH): 2 addresses.
✓ Nameserver names under 2 TLDs #12

Nameserver names use the TLDs .net, .nl.
i

Partly IPv6

These nameservers have no IPv6 address: ns1.tudelft.nl, ns2.tudelft.nl.

#13

Nameservers

info

8 of 8 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
ns1.surfnet.nl 192.87.106.101	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns1.surfnet.nl 2001:610:1:800a:192:87:106:101	NOERROR, 9 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns1.tudelft.nl 130.161.180.1	NOERROR, 11 ms, authoritative	no	yes / yes	refused	-
ns1.zurich.surf.net 195.176.255.9	NOERROR, 9 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surf.nl
ns1.zurich.surf.net 2001:620:0:9::1103	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surf.nl
ns2.surfnet.nl 192.87.36.2	NOERROR, 12 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns2.surfnet.nl 2001:610:3:200a:192:87:36:2	NOERROR, 13 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns2.tudelft.nl 130.161.180.65	NOERROR, 11 ms, authoritative	no	yes / yes	refused	-

Checks

✓ All respond #14

All 8 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.
i

Identifying string disclosed

These nameservers answer version queries with a string that is not a version number: ns1.surfnet.nl: "This is a SURFnet nameserver - dns-beheer@surfnet.nl"; ns1.zurich.surf.net: "This is a SURFnet nameserver - dns-beheer@surf.nl"; ns2.surfnet.nl: "This is a SURFnet nameserver - dns-beheer@surfnet.nl".

#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 2024575815 · primary ns1.tudelft.nl

Found

Primary (MNAME): ns1.tudelft.nl
Contact (RNAME): hostmaster.tudelft.nl
Serial: 2024575815
Refresh / retry: 36000 s / 3600 s
Expire: 2419200 s
Negative TTL: 3600 s

Serial per nameserver

Nameserver	Serial
ns1.surfnet.nl (192.87.106.101)	2024575815
ns1.surfnet.nl (2001:610:1:800a:192:87:106:101)	2024575815
ns1.tudelft.nl (130.161.180.1)	2024575815
ns1.zurich.surf.net (195.176.255.9)	2024575815
ns1.zurich.surf.net (2001:620:0:9::1103)	2024575815
ns2.surfnet.nl (192.87.36.2)	2024575815
ns2.surfnet.nl (2001:610:3:200a:192:87:36:2)	2024575815
ns2.tudelft.nl (130.161.180.65)	2024575815

Checks

✓ Serial 2024575815 everywhere #22

All nameservers serve the same version of the zone.
✓ Timers within recommendations #23

SOA refresh 10h, retry 1h, expire 28d, negative TTL 1h.
✓ Primary is a public nameserver #24

The primary nameserver ns1.tudelft.nl is one of the listed nameservers.
✓ Contact hostmaster@tudelft.nl #25

The SOA RNAME hostmaster.tudelft.nl means hostmaster@tudelft.nl.
✓ Timestamp serial #26

The serial 2024575815 is a Unix timestamp (2034-02-26 14:10 UTC).

DNSSEC

warn

Signed, DS published at parent

Found

Validated by resolver: yes
Denial of existence: NSEC3
NSEC3: 10 iterations, 14-byte salt
Signatures valid until: 25 October 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
26510	RSASHA256 (8)	SHA256 F6EE1BBCDA785F38…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
26510	KSK (257)	RSASHA256 (8)
14343	ZSK (256)	RSASHA256 (8)
35380	ZSK (256)	RSASHA256 (8)

Checks

✓ Signed and validated #27

The zone is signed, the parent publishes a DS record, and the resolver validates the answers.
✓ DS matches a key #28

The DS record at the parent matches a key in the zone: key tag 26510 (SHA256).
✓ Modern algorithms #29

Key algorithms: RSASHA256 (8).
✓ Short-lived signatures (online signing) #30

Signatures are valid for 97h0m0s and created on demand; the current one was made at 2026-10-21 00:18 UTC and expires at 2026-10-25 01:11 UTC.
!

NSEC3 with extra iterations or salt

NSEC3 uses 10 iterations and a 14-byte salt. RFC 9276 recommends 0 iterations and no salt: extra iterations cost resolvers CPU and add no real protection, and some validators treat high counts as insecure.

#31

Records

pass

40 records at the apex

Found

Read from: 192.87.106.101:53

Type	Value	TTL
SOA	ns1.tudelft.nl. hostmaster.tudelft.nl. 2024575815 36000 3600 2419200 3600	3600
NS	ns1.surfnet.nl.	3600
NS	ns1.tudelft.nl.	3600
NS	ns1.zurich.surf.net.	3600
NS	ns2.tudelft.nl.	3600
NS	ns2.surfnet.nl.	3600
A	130.161.128.82	600
MX	10 tudelft-nl.mail.protection.outlook.com.	3600
TXT	"EYCG94TF05LGAIXGKNS3B4SXZ796W7SPSHUPP1E3M"	3600
TXT	"HARICA-svOKy8ChPYfvbMCCCgv"	3600
TXT	"google-site-verification=vlPyHrqp8W5EwG3sBPAoZXrMFzyYmVJeDlDshyLCrzk"	3600
TXT	"figma-domain-verification=608b37abc404e00a10b2771e20c76b415cd1832b5faf4e3c500a545808eb4803-1775651511"	3600
TXT	"successfactors-site-verification=NGMxMTBlMzQ5ZmFiZWRiMTU1ZWVkZDk4MTczYzE5ZDhhZTVhNzI4NTI4OGZjYjI4OTc2YjYyM2RhNGNhZWI4Zg=="	3600
TXT	"google-site-verification=xwRqT1z_-EE597mEH4Qfh_TQTFYhTS-bWoYM009P-E8"	3600
TXT	"google-site-verification=_nk7k44TtWKQJSgLYer_J68BmKIY83V9Heax6u7oRRA"	3600
TXT	"miro-verification=034228b8046d801ff6579bb93100816ce0fac54f"	3600
TXT	"adobe-idp-site-verification=6c308adba5fba6d4295d8d092b40f332747dd3b7896740e9ee3a9c87e8691bb1"	3600
TXT	"amazonses:iyPCyEjMv6YpdMhVuagmzM+6PIiSZt+kj9J0DnmImnQ="	3600
TXT	"openatts a=dns-did; p=did:ethr:0x49264cd8041010adf43a926436e0ac38c053c066#controller; v=1.0;"	3600
TXT	"apple-domain-verification=TWilLuVqEqmPHPlP"	3600
TXT	"L4Rcgp2aufV3yNQT7HZ7nmdmW+S8VVsOkBuh2Rk4Z7WKyHrLcd/aKCgVE+sihdcNsi/LkDeS8otItlX8kSURUA=="	3600
TXT	"MS=ms66592311"	3600
TXT	"sendinblue-code:ef5755c78c2226424706a65a2413f0a1"	3600
TXT	"miro-verification=19371c38bfc06be58d667cbb59a02508a880607d"	3600
TXT	"HARICA-9s6oKKJ124kmU6v3f6A"	3600
TXT	"HARICA-aXJ2Kuvqc5hU8cVsyIR"	3600
TXT	"jamf-site-verification=Ddcd23-bTSJECc10j2URmw"	3600
TXT	"v=spf1 ip4:130.161.131.0/24 ip4:131.180.77.44 ip4:52.59.111.152 include:spf.protection.outlook.com ip4:46.31.188.52 ip4:212.83.209.198 ip4:212.83.209.204 include:spf.afas.online ip4:94.143.211.206 ip4:94.143.211.207 include:spf.recruitmail.com " "ip4:46.31.48.0/21 include:spf.topdesk.net include:spf.faqtory.nl include:a._spf.brightspace.com ip4:136.144.199.28 ip4:136.144.226.32 ip4:77.74.54.216 ip4:213.206.232.0/27 ip4:185.136.64.128/27 ip4:185.136.65.128/27 include:spf-x-tudelft-nl.dataduiker.app" " ~all"	3600
CAA	0 issue "amazonaws.com"	3600
CAA	0 iodef "mailto:abuse@tudelft.nl"	3600
CAA	0 issue "sectigo.com"	3600
CAA	0 issue "www.digicert.com"	3600
CAA	0 issue "amazontrust.com"	3600
CAA	0 issue "letsencrypt.org"	3600
CAA	0 issue "harica.gr"	3600
CAA	0 issue "awstrust.com"	3600
CAA	0 issuewild "harica.gr"	3600
CAA	0 issue "amazon.com"	3600
CAA	0 issue "pki.goog"	3600
CAA	0 issuemail "harica.gr"	3600

Checks

✓ TTLs within range #32

TTLs: A 10m, MX 1h, NS 1h.
✓ No CNAME at the apex #33

The zone apex has no CNAME record.
✓ No wildcard #34

Names that don't exist return NXDOMAIN.
✓ CAA restricts issuance #35

Certificates may be issued by: amazonaws.com, sectigo.com, www.digicert.com, amazontrust.com, letsencrypt.org, harica.gr, awstrust.com, amazon.com, pki.goog.