Report for 23503

Name

CONSTELLATION-ENERGY - Exelon Corporation, US

AS Adjacency Report

In the context of this report "Upstream" indicates that there is an adjacent AS that lines between the BGP table collection point (in this case at AS6447) and the specified AS. Similarly, "Downstream" refers to an adjacent AS that lies beyond the specified AS. This upstream / downstream categorisation is strictly a description relative topology, and should not be confused with provider / customer / peer inter-AS relationships.

23503 CONSTELLATION-ENERGY, US

  Adjacency:     4  Upstream:     3  Downstream:     1
  Upstream Adjacent AS list
    AS202           CENTURYLINK-LEGACY-LVLT-202, US
    AS26425         EXELON-CORPORATION, US
    AS1321          ANSBB-ASNNET-1, US
  Downstream Adjacent AS list
    AS26425         EXELON-CORPORATION, US

Announced Prefixes

Rank  AS       Type    Originate Addr Space  (pfx)   Transit Addr space  (pfx)  Description
12490 AS23503        ORG+TRN Originate:       7680 /19.09  Transit:      28672 /17.19 CONSTELLATION-ENERGY, US

Aggregation Suggestions

        Filter: Aggregates, Specifics

This report does not take into account conditions local to each origin AS in terms of policy or traffic engineering requirements, so this is an approximate guideline as to aggregation possibilities.

 Rank AS            AS Name                                      Current  Wthdw  Aggte  Annce Redctn       %
21640 AS23503       CONSTELLATION-ENERGY, US                          14      2      1     13      1   7.14%


  Prefix               AS Path                              Aggregation Suggestion
  159.214.87.0/24      2914 703 1321 23503    
  216.99.176.0/20      6939 3356 202 26425 26425 26425 26425 23503   
  216.99.176.0/23      7018 3356 202 23503    
  216.99.179.0/24      6939 3356 202 23503    
  216.99.180.0/24      6939 3356 202 23503    
  216.99.181.0/24      7018 3356 202 23503    
  216.99.182.0/24      7018 3356 202 23503    
  216.99.183.0/24      6939 3356 202 23503    
  216.99.185.0/24      7018 3356 202 23503    
  216.99.186.0/23      7018 3356 202 23503  + Announce - aggregate of 216.99.186.0/24 (7018 3356 202 23503) and 216.99.187.0/24 (7018 3356 202 23503)
  216.99.186.0/24      7018 3356 202 23503  - Withdrawn - aggregated with 216.99.187.0/24 (7018 3356 202 23503)
  216.99.187.0/24      7018 3356 202 23503  - Withdrawn - aggregated with 216.99.186.0/24 (7018 3356 202 23503)
  216.99.188.0/24      7018 3356 202 23503    
  216.99.189.0/24      6939 3356 202 23503    
  216.99.191.0/24      7018 3356 202 23503    

Advertisements that are fragments of the original RIR allocation (more specifics) originated by this AS.

AS23503   30 More Specifics   33 Total Advertisements   CONSTELLATION-ENERGY, US
    138.39.7.0/24                 138.39.0.0/16
    138.39.22.0/24                138.39.0.0/16
    138.39.23.0/24                138.39.0.0/16
    138.39.24.0/24                138.39.0.0/16
    138.39.47.0/24                138.39.0.0/16
    161.186.6.0/24                161.186.0.0/16
    161.186.88.0/24               161.186.0.0/16
    161.186.89.0/24               161.186.0.0/16
    161.186.93.0/24               161.186.0.0/16
    161.186.147.0/24              161.186.0.0/16
    161.186.148.0/24              161.186.0.0/16
    161.186.151.0/24              161.186.0.0/16
    198.29.128.0/19               198.29.128.0/18
    198.29.160.0/20               198.29.128.0/18
    198.29.176.0/22               198.29.128.0/18
    198.29.182.0/23               198.29.128.0/18
    198.29.184.0/21               198.29.128.0/18
    216.99.176.0/23               216.99.176.0/20
    216.99.179.0/24               216.99.176.0/20
    216.99.180.0/24               216.99.176.0/20
    216.99.181.0/24               216.99.176.0/20
    216.99.182.0/24               216.99.176.0/20
    216.99.183.0/24               216.99.176.0/20
    216.99.184.0/24               216.99.176.0/20
    216.99.185.0/24               216.99.176.0/20
    216.99.186.0/24               216.99.176.0/20
    216.99.187.0/24               216.99.176.0/20
    216.99.188.0/24               216.99.176.0/20
    216.99.189.0/24               216.99.176.0/20
    216.99.191.0/24               216.99.176.0/20
    159.214.87.0/24               159.214.0.0/17

Prefixes added and withdrawn by this origin AS in the past 7 days.

    + 138.39.7.0/24               Announced
    + 138.39.22.0/24              Announced
    + 138.39.23.0/24              Announced
    + 138.39.24.0/24              Announced
    + 138.39.47.0/24              Announced
    + 161.186.6.0/24              Announced
    + 161.186.88.0/24             Announced
    + 161.186.89.0/24             Announced
    + 161.186.93.0/24             Announced
    + 161.186.147.0/24            Announced
    + 161.186.148.0/24            Announced
    + 161.186.151.0/24            Announced
    + 198.29.128.0/19             Announced
    + 198.29.160.0/20             Announced
    + 198.29.176.0/22             Announced
    + 198.29.182.0/23             Announced
    + 198.29.184.0/21             Announced
    + 198.29.192.0/19             Announced
    + 198.29.224.0/20             Announced
    + 198.29.252.0/23             Announced
    + 216.99.182.0/24             Announced
    + 216.99.184.0/24             Announced
    + 216.99.187.0/24             Announced
    - 159.214.87.0/24             Withdrawn
    - 216.99.176.0/20             Withdrawn

Whois Entry

whois: 402590

IANA has recorded AS23503 as originally allocated by 
/usr/bin/whois -h jwhois.apnic.netr "AS23503\n             
             #
             # ARIN WHOIS data and services are subject to the Terms of Use
             # available at: https://www.arin.net/resources/registry/whois/tou/
             #
             # If you see inaccuracies in the results, please report at
             # https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
             #
             # Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
             #
             
             
             ASNumber:       23503
             ASName:         CONSTELLATION-ENERGY
             ASHandle:       AS23503
             RegDate:        2002-03-29
             Updated:        2016-08-08
             Ref:            https://rdap.arin.net/registry/autnum/23503
             
             
             OrgName:        Exelon Corporation
             OrgId:          EXELO
             Address:        10 S Dearborn St
             City:           Chicago
             StateProv:      IL
             PostalCode:     60603
             Country:        US
             RegDate:        2002-09-12
             Updated:        2019-02-26
             Ref:            https://rdap.arin.net/registry/entity/EXELO
             
             
             OrgNOCHandle: NOC1756-ARIN
             OrgNOCName:   Network Operations Center
             OrgNOCPhone:  +1-410-470-1200 
             OrgNOCEmail:  netadmin2@exeloncorp.com
             OrgNOCRef:    https://rdap.arin.net/registry/entity/NOC1756-ARIN
             
             OrgAbuseHandle: NOC1756-ARIN
             OrgAbuseName:   Network Operations Center
             OrgAbusePhone:  +1-410-470-1200 
             OrgAbuseEmail:  netadmin2@exeloncorp.com
             OrgAbuseRef:    https://rdap.arin.net/registry/entity/NOC1756-ARIN
             
             OrgTechHandle: NOC1756-ARIN
             OrgTechName:   Network Operations Center
             OrgTechPhone:  +1-410-470-1200 
             OrgTechEmail:  netadmin2@exeloncorp.com
             OrgTechRef:    https://rdap.arin.net/registry/entity/NOC1756-ARIN
             
             RTechHandle: NOC1756-ARIN
             RTechName:   Network Operations Center
             RTechPhone:  +1-410-470-1200 
             RTechEmail:  netadmin2@exeloncorp.com
             RTechRef:    https://rdap.arin.net/registry/entity/NOC1756-ARIN
             
             RAbuseHandle: NOC1756-ARIN
             RAbuseName:   Network Operations Center
             RAbusePhone:  +1-410-470-1200 
             RAbuseEmail:  netadmin2@exeloncorp.com
             RAbuseRef:    https://rdap.arin.net/registry/entity/NOC1756-ARIN
             
             
             #
             # ARIN WHOIS data and services are subject to the Terms of Use
             # available at: https://www.arin.net/resources/registry/whois/tou/
             #
             # If you see inaccuracies in the results, please report at
             # https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
             #
             # Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
             #