AS13037 — ZEN-AS Zen Internet - UK

Network type: residential

AS13037 announces 36 IPv4 prefixes covering 527,616 addresses and 1 IPv6 prefixes.

About this network

An ISP whose forward hostnames contain the label in-addr, borrowed from the reverse tree.

What it's used for

• A British internet provider. 527,616 addresses across 36 IPv4 prefixes, one IPv6 prefix, and 94 observed BGP neighbours.

Notable

• Netnames are mostly UK-ZEN, dated 20010629, 20020703, 20030428 and 20100604, with two left bare.
• One breaks the pattern entirely: ZEN20110301-DAR-ZEN-ADSL13, date first, no country prefix, and a suffix naming a product and a numbered block.
• Sixteen of eighteen sampled addresses returned names in two forms: 82-68-128-0.dsl.in-addr.zen.co.uk and 51-148-64-0.dsl.zen.co.uk.
• One address answers mailgate.cj-dev.uk, a customer's own domain.

Interesting

• in-addr inside a forward hostname is the record worth pausing on. That label belongs to in-addr.arpa, the tree reverse lookups are answered from; it has no meaning under zen.co.uk. Someone building the generated zone copied the shape of the reverse hierarchy into the forward name, and the newer blocks dropped it. Two generations of the same script are visible side by side.
• A customer domain appearing in the middle of ISP-generated space means that address has a manually set name overriding the template. Business lines get named for what they run; consumer lines get named for their address.
• Six dated netnames spanning 2001 to 2011 track a provider that kept coming back for more space across a decade.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy.

Announced prefixes

• 51.148.0.0/16
• 51.155.0.0/16
• 62.3.64.0/18
• 77.104.128.0/18
• 82.68.0.0/15
• 82.71.0.0/16
• 88.97.0.0/18
• 88.97.64.0/20
• 88.97.88.0/22
• 88.97.96.0/20
• 88.98.0.0/20
• 88.98.16.0/23
• 88.98.18.0/24
• 88.98.21.0/24
• 88.98.22.0/23
• 88.98.24.0/21
• 88.98.32.0/19
• 88.98.64.0/19
• 88.98.128.0/19
• 88.98.160.0/21
• 88.98.170.0/23
• 88.98.172.0/22
• 88.98.176.0/20
• 91.235.214.0/24
• 146.66.64.0/18
• 185.6.135.0/24
• 185.81.232.0/22
• 185.169.116.0/22
• 185.183.100.0/22
• 188.122.32.0/20
• 188.122.48.0/21
• 188.122.56.0/22
• 188.122.60.0/23
• 188.122.63.0/24
• 212.23.0.0/19
• 217.155.0.0/16
• 2a02:8010::/29

Upstream networks

• AS1299 Arelion Sweden AB
• AS6939 Hurricane Electric LLC
• AS6461 Zayo Bandwidth
• AS2914 NTT America, Inc.
• AS9002 RETN Limited
• AS37721 Virtual Technologies & Solutions
• AS33891 Core-Backbone GmbH
• AS50300 CustodianDC Limited
• AS24482 SG.GS
• AS48185 team.blue NV
• AS42708 Glesys AB
• AS31500 Global Network Management Inc
• AS3741 Dimension Data
• AS57463 NetIX Communications JSC
• AS12552 GlobalConnect AB
• AS8966 EMIRATES TELECOMMUNICATIONS GROUP COMPANY (ETISALAT GROUP) PJSC
• AS13030 Init7 (Switzerland) Ltd.

Downstream networks

• AS208697 Kellogg Management Services (Europe) Limited
• AS51766 Merseyside Fire and Rescue Service
• AS44697 Computer & Communication Co. Limited

Adjacent networks

• AS1299 Arelion Sweden AB
• AS6461 Zayo Bandwidth
• AS6939 Hurricane Electric LLC
• AS2914 NTT America, Inc.
• AS9002 RETN Limited
• AS208697 Kellogg Management Services (Europe) Limited
• AS51766 Merseyside Fire and Rescue Service
• AS37721 Virtual Technologies & Solutions
• AS48185 team.blue NV
• AS3741 Dimension Data
• AS57463 NetIX Communications JSC
• AS24482 SG.GS
• AS50300 CustodianDC Limited
• AS42708 Glesys AB
• AS12552 GlobalConnect AB
• AS33891 Core-Backbone GmbH
• AS31500 Global Network Management Inc
• AS44697 Computer & Communication Co. Limited
• AS13030 Init7 (Switzerland) Ltd.
• AS8966 EMIRATES TELECOMMUNICATIONS GROUP COMPANY (ETISALAT GROUP) PJSC

Internet exchanges

• LINX LON1 — London, United Kingdom
• London Network Access Point — London, United Kingdom
• LINX Manchester — Manchester, United Kingdom