Domain report: summacollege.nl

Registration

info

.nl country-code

Found

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

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

#3

Delegation

pass

ns1.surfnet.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns3.surfnet.nl

Found

Parent zone: nl
Delegation from: ns1.dns.nl (194.0.28.53)
NS at the parent: ns1.surfnet.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns3.surfnet.nl
NS in the zone: ns1.surfnet.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns3.surfnet.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.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
ns3.surfnet.nl	195.169.124.71 2001:610:0:800c:195:169:124:71	AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL	195.169.124.71 2001:610:0:800c:195:169:124:71

Checks

✓ 4 nameservers #6

Delegated to ns1.surfnet.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns3.surfnet.nl.
✓ 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 4 IPv4 /24s and 4 IPv6 /48s.
✓ 2 autonomous systems #11

The nameservers are spread over: AS1103 (SURFNET-NL - SURF B.V., NL): 6 addresses; AS559 (Switch - SWITCH, CH): 2 addresses.
✓ Nameserver names under 2 TLDs #12

Nameserver names use the TLDs .net, .nl.
✓ All reachable over IPv6 #13

Every nameserver has an IPv6 address.

Nameservers

info

8 of 8 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
ns1.surfnet.nl 192.87.106.101	NOERROR, 11 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, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
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, 12 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns3.surfnet.nl 195.169.124.71	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns3.surfnet.nl 2001:610:0:800c:195:169:124:71	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl

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"; ns3.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 2026101501 · primary ns1.surfnet.nl

Found

Primary (MNAME): ns1.surfnet.nl
Contact (RNAME): netwerkbeheer.summacollege.nl
Serial: 2026101501
Refresh / retry: 28800 s / 7200 s
Expire: 2419200 s
Negative TTL: 3600 s

Serial per nameserver

Nameserver	Serial
ns1.surfnet.nl (192.87.106.101)	2026101501
ns1.surfnet.nl (2001:610:1:800a:192:87:106:101)	2026101501
ns1.zurich.surf.net (195.176.255.9)	2026101501
ns1.zurich.surf.net (2001:620:0:9::1103)	2026101501
ns2.surfnet.nl (192.87.36.2)	2026101501
ns2.surfnet.nl (2001:610:3:200a:192:87:36:2)	2026101501
ns3.surfnet.nl (195.169.124.71)	2026101501
ns3.surfnet.nl (2001:610:0:800c:195:169:124:71)	2026101501

Checks

✓ Serial 2026101501 everywhere #22

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

SOA refresh 8h, retry 2h, expire 28d, negative TTL 1h.
✓ Primary is a public nameserver #24

The primary nameserver ns1.surfnet.nl is one of the listed nameservers.
✓ Contact netwerkbeheer@summacollege.nl #25

The SOA RNAME netwerkbeheer.summacollege.nl means netwerkbeheer@summacollege.nl.
✓ Date-based serial #26

The serial 2026101501 follows the YYYYMMDDnn convention (2026-10-15).

DNSSEC

info

Signed, DS published at parent

Found

Validated by resolver: yes
Denial of existence: NSEC
Signatures valid until: 14 November 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
50122	ECDSAP256SHA256 (13)	SHA256 C990102273627BB4…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
45734	ZSK (256)	ECDSAP256SHA256 (13)
23283	KSK (257)	ECDSAP256SHA256 (13)
42500	ZSK (256)	ECDSAP256SHA256 (13)
50122	KSK (257)	ECDSAP256SHA256 (13)

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 50122 (SHA256).
✓ Modern algorithms #29

Key algorithms: ECDSAP256SHA256 (13).
✓ Signatures valid until 2026-11-14 #30

The earliest DNSKEY/SOA signature expires at 2026-11-14 00:02 UTC.
i

NSEC

The zone uses NSEC, so its full contents can be listed by walking the NSEC chain. That is fine unless the names are sensitive.

#31

Records

pass

34 records at the apex

Found

Read from: 192.87.106.101:53

Type	Value	TTL
SOA	ns1.surfnet.nl. netwerkbeheer.summacollege.nl. 2026101501 28800 7200 2419200 3600	3600
NS	ns1.zurich.surf.net.	3600
NS	ns3.surfnet.nl.	3600
NS	ns2.surfnet.nl.	3600
NS	ns1.surfnet.nl.	3600
A	213.206.225.30	3600
AAAA	2001:4018:8800:3::72	3600
MX	10 summacollege-nl.l-v1.mx.microsoft.	3600
TXT	"v=spf1 ip4:194.171.48.136 ip4:194.171.48.179 include:spf.protection.outlook.com include:servers.mcsv.net include:spf.mandrillapp.com include:_spf.spotler.email -all"	3600
TXT	"openai-domain-verification=dv-0zvfpzfztFEjEV43hWT0ZdIw"	3600
TXT	"_ozafeorgblx2898c6myvpuyp1jr31xk"	3600
TXT	"google-site-verification=TFXYWvb6fpnSfJIHAJNi6JNNM5iRlYTLma1TggSaXbM"	3600
TXT	"_f830mlnz44ghxtto4utw5edirtw9xmv"	3600
TXT	"_64602ajq81w2exf2fqh1vlp6e9esn14"	3600
TXT	"_2xik322yxl718xbepmgr59a1czto26e"	3600
TXT	"_paqmiqw3tfkaqrennzhx1fejc6qeivp"	3600
TXT	"_3wv7anq8gktds5gws3x45m6tmwmfwfr"	3600
TXT	"_r7uoirlp0h22q0yunops6f1zej8fvjq"	3600
TXT	"_pfxrh873z86yu6kbdg7dlf9hafih7r9"	3600
TXT	"_lb6gf5mfonza1minliqwnoq9n2ld8p8"	3600
TXT	"_vvzla4kkk3hx9c3h5z18kgy5fbzu5ec"	3600
TXT	"_sjoptfks270n9zpbey2es3rivyewwsg"	3600
TXT	"remarkable-domain-verification=ac63f41d-7910-4471-aa6f-15fd8cc44b30"	3600
TXT	"apple-domain-verification=sPAGmtn5JGfxdZYs"	3600
TXT	"adobe-idp-site-verification=329f8b8304246943ff233412d6a1b20b5176a986760081441f99d8d012f04c16"	3600
TXT	"atlassian-domain-verification=4lqouAfaXPfcJANTmh2EE4lvjxCF9aB4leTXh860yCRhIih4iRlEsfThxEoR1t1X"	3600
TXT	"MS=ms90744302"	3600
CAA	0 issuewild "digicert.com"	3600
CAA	0 issue "www.pkioverheid.nl"	3600
CAA	0 issue "sectigo.com"	3600
CAA	0 issue "letsencrypt.org"	3600
CAA	0 issue "digicert.com"	3600
CAA	0 issue "kpn.com"	3600
CAA	0 iodef "mailto:netwerkbeheer@summacollege.nl"	3600

Checks

✓ TTLs within range #32

TTLs: A 1h, AAAA 1h, 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: digicert.com, www.pkioverheid.nl, sectigo.com, letsencrypt.org, kpn.com.