ASN AS21301 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS21301?

AS21301 is listed under Natwest Markets PLC.

What do peers, upstreams, and downstreams mean in ASN data?

Peers are lateral network interconnections, upstreams are transit providers, and downstreams are customer networks receiving connectivity.

What are routes and IP ranges for an ASN?

Routes and IP ranges are the network prefixes announced by the ASN on the internet and show the address space it originates.

Why is WHOIS data shown for an ASN?

WHOIS data provides registration and contact context for ASN ownership, administration, and operational reference.

How can I access the full ASN tables?

The page shows a preview of large ASN datasets. Use the page controls to load more rows, and upgrade to a paid plan for complete access.

AS21301 Natwest Markets PLC | IPGeolocation.io

ASN Lookup Tool

Natwest Markets PLC o2.com

GB 10 Routes

AS Data

AS21301

AS21301 – Natwest Markets PLC

AS Number	21301
AS Name	UK-NATWEST-AS21301
Organization	Natwest Markets PLC (org-trbo1-ripe)
Country	GB
Website	o2.com
Number of IPv4 Routes	10
Number of IPv6 Routes	0
ASN type	BUSINESS
Allocation Status	ASSIGNED
Registry	RIPE
Date Allocated	2001-10-24

ASN Intelligence API for production workflows

Use ASN data for AS21301 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

Access complete peers, upstreams, downstreams, routes, WHOIS, and contact intelligence via our API. Learn more

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
155.136.59.0/24	AS21301	Natwest Markets PLC	Royal Bank of Scotland	256
155.136.202.0/23	AS21054	Natwest Markets PLC	Royal Bank of Scotland	512
155.136.56.0/24	AS21301	Natwest Markets PLC	Royal Bank of Scotland	256
155.136.56.0/22	AS21301	Natwest Markets PLC	Royal Bank of Scotland	1024
155.136.200.0/23	AS21301	Natwest Markets PLC	Royal Bank of Scotland	512
155.136.151.0/24	AS21301	Natwest Markets PLC	Royal Bank of Scotland	256
155.136.200.0/24	AS21301	Natwest Markets PLC	Royal Bank of Scotland	256
155.136.58.0/24	AS21301	Natwest Markets PLC	Royal Bank of Scotland	256
155.136.57.0/24	AS21301	Natwest Markets PLC	Royal Bank of Scotland	256
155.136.201.0/24	AS21301	Natwest Markets PLC	Royal Bank of Scotland	256

Raw Whois Response

% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See https://docs.db.ripe.net/terms-conditions.html

% Note: this output has been filtered.
%       To receive output for a database update, use the "-B" flag.

% Information related to 'AS21281 - AS21390'

as-block:       AS21281 - AS21390
descr:          RIPE NCC ASN block
remarks:        These AS Numbers are assigned to network operators in the RIPE NCC service region.
mnt-by:         RIPE-NCC-HM-MNT
created:        2018-11-22T15:27:28Z
last-modified:  2018-11-22T15:27:28Z
source:         RIPE

% Information related to 'AS21301'

% Abuse contact for 'AS21301' is 'abuse.cz@o2.com'

aut-num:        AS21301
as-name:        UK-NATWEST-AS21301
descr:          EDINBURGH
org:            ORG-TRBo1-RIPE
import:         from AS1273 action pref=100; accept ANY
import:         from AS32787 action pref=100; accept ANY
import:         from AS2856 action pref=100; accept ANY
export:         to AS1273 announce AS21301
export:         to AS32787 announce AS21301
export:         to AS2856 announce AS21301
tech-c:         RTST1-RIPE
status:         ASSIGNED
mnt-by:         RIPE-NCC-END-MNT
admin-c:        CL5041-RIPE
mnt-by:         RBSG-MNT
created:        2001-10-24T12:23:55Z
last-modified:  2026-04-10T15:50:30Z
source:         RIPE
sponsoring-org: ORG-UA24-RIPE

organisation:   ORG-TRBo1-RIPE
org-name:       Natwest Markets PLC
country:        GB
org-type:       other
address:        135 Bishopsgate London EC2M 3UR UK
abuse-c:        AR30109-RIPE
phone:          +44 20 3361 7879
mnt-ref:        AS1849-MNT
mnt-by:         AS1849-MNT
created:        2009-12-18T13:54:36Z
last-modified:  2023-10-31T10:49:07Z
source:         RIPE # Filtered

role:           Technical Role
address:        250 Bishopsgate
address:        London
address:        EC2M 3UR
abuse-mailbox:  ripe-abuse@rbs.com
nic-hdl:        RTST1-RIPE
mnt-by:         RBSG-MNT
created:        2018-03-23T12:27:34Z
last-modified:  2026-04-10T15:08:40Z
source:         RIPE # Filtered

person:         Sean Jarvis
address:        250 Bishopsgate
address:        London
address:        EC2M 3UR
phone:          +44 7972 792793
nic-hdl:        CL5041-RIPE
mnt-by:         RBSG-MNT
created:        2012-08-13T13:30:01Z
last-modified:  2026-04-10T14:49:33Z
source:         RIPE # Filtered

% This query was served by the RIPE Database Query Service version 1.121.2 (ABERDEEN)

Parsed Whois Response

{
  "status" : true,
  "whois_server" : "whois.ripe.net",
  "as_blocks" : [ {
    "as_block" : "AS21281 - AS21390",
    "description" : [ "RIPE NCC ASN block" ],
    "remarks" : [ "These AS Numbers are assigned to network operators in the RIPE NCC service region." ],
    "mnt_by" : [ "RIPE-NCC-HM-MNT" ],
    "date_created" : "2018-11-22",
    "date_updated" : "2018-11-22",
    "source" : "RIPE"
  } ],
  "aut_nums" : [ {
    "aut_num" : "AS21301",
    "as_name" : "UK-NATWEST-AS21301",
    "description" : [ "EDINBURGH" ],
    "status" : "ASSIGNED",
    "import" : [ "from AS1273 action pref=100; accept ANY", "from AS32787 action pref=100; accept ANY", "from AS2856 action pref=100; accept ANY" ],
    "export" : [ "to AS1273 announce AS21301", "to AS32787 announce AS21301", "to AS2856 announce AS21301" ],
    "organization" : "ORG-TRBo1-RIPE",
    "sponsoring_organization" : "ORG-UA24-RIPE",
    "admin_contacts" : [ "CL5041-RIPE" ],
    "tech_contacts" : [ "RTST1-RIPE" ],
    "mnt_by" : [ "RIPE-NCC-END-MNT", "RBSG-MNT" ],
    "date_created" : "2001-10-24",
    "date_updated" : "2026-04-10",
    "source" : "RIPE"
  } ],
  "organization" : {
    "handle" : "ORG-TRBo1-RIPE",
    "name" : "Natwest Markets PLC",
    "type" : "other",
    "address" : [ "135 Bishopsgate London EC2M 3UR UK" ],
    "street" : "Bishopsgate",
    "city" : "London",
    "zip_code" : "EC2M 3UR",
    "country" : [ "GB" ],
    "phone" : [ "+44 20 3361 7879" ],
    "abuse_contacts" : [ "AR30109-RIPE" ],
    "mnt_ref" : [ "AS1849-MNT" ],
    "mnt_by" : [ "AS1849-MNT" ],
    "date_created" : "2009-12-18",
    "date_updated" : "2023-10-31",
    "source" : "RIPE",
    "addressCountry" : "UK"
  },
  "administrative_contacts" : [ {
    "handle" : "CL5041-RIPE",
    "name" : "Sean Jarvis",
    "address" : [ "250 Bishopsgate", "London", "EC2M 3UR" ],
    "street" : "Bishopsgate",
    "city" : "London",
    "zip_code" : "EC2M 3UR",
    "phone" : [ "+44 7972 792793" ],
    "mnt_by" : [ "RBSG-MNT" ],
    "date_created" : "2012-08-13",
    "date_updated" : "2026-04-10",
    "source" : "RIPE"
  } ],
  "technical_contacts" : [ {
    "handle" : "RTST1-RIPE",
    "name" : "Technical Role",
    "address" : [ "250 Bishopsgate", "London", "EC2M 3UR" ],
    "street" : "Bishopsgate",
    "city" : "London",
    "zip_code" : "EC2M 3UR",
    "abuse_mailbox" : [ "ripe-abuse@rbs.com" ],
    "mnt_by" : [ "RBSG-MNT" ],
    "date_created" : "2018-03-23",
    "date_updated" : "2026-04-10",
    "source" : "RIPE"
  } ]
}

Peers

AS Number	Description	Country
AS2856	British Telecommunications PLC	GB
AS1273	Vodafone Group PLC	GB
AS1273	Vodafone Group PLC	NL
AS32787	Akamai Technologies, Inc.	US

Upstreams

AS Number	Description	Country
AS2856	British Telecommunications PLC	GB
AS1273	Vodafone Group PLC	NL
AS32787	Akamai Technologies, Inc.	US

Legacy Routes

155.136.144.0/24 155.136.146.0/24