CERFnet

IPv4 IPv6

Networks by country: United States United States (121), United Kingdom United Kingdom (1), Italy Italy (1), Canada Canada (1)

Assigned AS: AS1740, AS1838
Updated: 03 July 2020

We found 113 IPv4 networks operated by this organization.
The first 100 networks are displayed.
Results sorted by network size.

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CIDR: 199.104.0.0/14
IP Range: 199.105.0.0 - 199.108.255.255
Block size: 262,144

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United States CERFnet
CERFNET-BLK-206

CIDR: 206.16.0.0/14
IP Range: 206.16.0.0 - 206.19.255.255
Block size: 262,144

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United States CERFnet
CERFNET-BLK-5

CIDR: N/A
IP Range: 63.240.0.0 - 63.242.255.255
Block size: 196,608

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United States CERFnet
CERFNET-BLK-3

CIDR: 209.186.0.0/15
IP Range: 209.186.0.0 - 209.187.255.255
Block size: 131,072

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United Kingdom CERFnet
ATTGNS

CIDR: 149.17.0.0/16
IP Range: 149.17.0.0 - 149.17.255.255
Block size: 65,536

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United States CERFnet
CERFNET-BLK-4

CIDR: 216.148.0.0/16
IP Range: 216.148.0.0 - 216.148.255.255
Block size: 65,536

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United States CERFnet
NETBLK-CERFNET

CIDR: 192.215.0.0/16
IP Range: 192.215.0.0 - 192.215.255.255
Block size: 65,536

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Italy CERFnet
CERFNET-BLK-207

CIDR: 207.252.0.0/16
IP Range: 207.252.0.0 - 207.252.255.255
Block size: 65,536

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United States CERFnet
CERFNET

CIDR: 134.24.0.0/16
IP Range: 134.24.0.0 - 134.24.255.255
Block size: 65,536

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United States CERFnet
ATTENS-SEA1-1

CIDR: 12.129.0.0/18
IP Range: 12.129.0.0 - 12.129.63.255
Block size: 16,384

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United States CERFnet
ATTENS-ATL1-1

CIDR: 12.129.64.0/18
IP Range: 12.129.64.0 - 12.129.127.255
Block size: 16,384

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United States CERFnet
ATTENS-LAX1-1

CIDR: 12.129.192.0/18
IP Range: 12.129.192.0 - 12.129.255.255
Block size: 16,384

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United States CERFnet
ATTENS-BOS1-1

CIDR: 12.130.0.0/18
IP Range: 12.130.0.0 - 12.130.63.255
Block size: 16,384

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United States CERFnet
ATTENS-SJC1-2

CIDR: 12.130.128.0/18
IP Range: 12.130.128.0 - 12.130.191.255
Block size: 16,384

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CIDR: 12.130.192.0/18
IP Range: 12.130.192.0 - 12.130.255.255
Block size: 16,384

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CIDR: 12.130.96.0/19
IP Range: 12.130.96.0 - 12.130.127.255
Block size: 8,192

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United States CERFnet
CERF-WEB-NYC-2

CIDR: 209.187.176.0/20
IP Range: 209.187.176.0 - 209.187.191.255
Block size: 4,096

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United States CERFnet
ATTENS-SAN2-1

CIDR: 12.130.64.0/20
IP Range: 12.130.64.0 - 12.130.79.255
Block size: 4,096

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United States CERFnet
ATTENS-IDCBLK-1

CIDR: 12.130.80.0/20
IP Range: 12.130.80.0 - 12.130.95.255
Block size: 4,096

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United States CERFnet
CERF-DSL-NYC-3

CIDR: 209.187.8.0/21
IP Range: 209.187.8.0 - 209.187.15.255
Block size: 2,048

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United States CERFnet
CERF-DSL-BOS-1

CIDR: 209.187.120.0/21
IP Range: 209.187.120.0 - 209.187.127.255
Block size: 2,048

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United States CERFnet
CERF-DSL-BOS-2

CIDR: 209.187.144.0/21
IP Range: 209.187.144.0 - 209.187.151.255
Block size: 2,048

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United States CERFnet
CERF-DSL-CHI-2

CIDR: 209.187.192.0/21
IP Range: 209.187.192.0 - 209.187.199.255
Block size: 2,048

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United States CERFnet San Diego ISDN Subnet
CERF-SANISDN-A

CIDR: 206.19.212.0/22
IP Range: 206.19.212.0 - 206.19.215.255
Block size: 1,024

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United States Sterling Communications
STERLING-B

CIDR: 216.148.104.0/23
IP Range: 216.148.104.0 - 216.148.105.255
Block size: 512

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United States CERFnet San Diego ISDN Subnets
CERF-SDISDN

CIDR: 199.106.6.0/23
IP Range: 199.106.6.0 - 199.106.7.255
Block size: 512

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United States CERFnet Houston ISDN Subnet
CERF-HOUISDN-A

CIDR: 209.186.38.0/24
IP Range: 209.186.38.0 - 209.186.38.255
Block size: 256

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United States Leon Plastics
CERF-LEONPLASTICS-A

CIDR: 209.187.244.0/24
IP Range: 209.187.244.0 - 209.187.244.255
Block size: 256

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United States CERFnet
CERFNET-OPER

CIDR: 192.102.249.0/24
IP Range: 192.102.249.0 - 192.102.249.255
Block size: 256

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United States CERFnet
CERFNET-OP2

CIDR: 192.153.156.0/24
IP Range: 192.153.156.0 - 192.153.156.255
Block size: 256

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CIDR: 192.215.11.0/24
IP Range: 192.215.11.0 - 192.215.11.255
Block size: 256

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United States CERFnet
CERFNET-12

CIDR: 192.215.12.0/24
IP Range: 192.215.12.0 - 192.215.12.255
Block size: 256

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CIDR: 192.215.13.0/24
IP Range: 192.215.13.0 - 192.215.13.255
Block size: 256

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United States CERFnet
CERFNET-15

CIDR: 192.215.15.0/24
IP Range: 192.215.15.0 - 192.215.15.255
Block size: 256

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United States CERFnet
CERFNET-16

CIDR: 192.215.16.0/24
IP Range: 192.215.16.0 - 192.215.16.255
Block size: 256

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CIDR: 192.215.18.0/24
IP Range: 192.215.18.0 - 192.215.18.255
Block size: 256

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CIDR: 192.215.23.0/24
IP Range: 192.215.23.0 - 192.215.23.255
Block size: 256

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United States Cerfnet
CERFNET-26

CIDR: 192.215.26.0/24
IP Range: 192.215.26.0 - 192.215.26.255
Block size: 256

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United States CERFnet
DDI-COM

CIDR: 192.215.28.0/24
IP Range: 192.215.28.0 - 192.215.28.255
Block size: 256

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CIDR: 192.215.30.0/24
IP Range: 192.215.30.0 - 192.215.30.255
Block size: 256

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CIDR: 192.215.31.0/24
IP Range: 192.215.31.0 - 192.215.31.255
Block size: 256

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CIDR: 192.215.34.0/24
IP Range: 192.215.34.0 - 192.215.34.255
Block size: 256

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CIDR: 192.215.35.0/24
IP Range: 192.215.35.0 - 192.215.35.255
Block size: 256

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United States CERFnet Pittsburgh ISDN Subnet
CERF-PITTISDN-A

CIDR: 207.252.7.0/24
IP Range: 207.252.7.0 - 207.252.7.255
Block size: 256

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United States CERFnet Dayton Chorus/Co-Lo Subnet
CERF-DAYTONCOLO

CIDR: 207.252.11.0/24
IP Range: 207.252.11.0 - 207.252.11.255
Block size: 256

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United States CERFnet Denver ISDN Subnet
CERF-DENISDN-A

CIDR: 207.252.13.0/24
IP Range: 207.252.13.0 - 207.252.13.255
Block size: 256

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United States CERFnet Detroit Customer Subnet
CERF-DETSUB

CIDR: 207.252.175.0/24
IP Range: 207.252.175.0 - 207.252.175.255
Block size: 256

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United States CERFnet Pittsburgh Customer Subnet
CERF-PITTSUB

CIDR: 207.252.187.0/24
IP Range: 207.252.187.0 - 207.252.187.255
Block size: 256

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United States CERFnet Dallas ISDN Subnet
CERF-DALISDN-A

CIDR: 207.252.217.0/24
IP Range: 207.252.217.0 - 207.252.217.255
Block size: 256

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United States Curtis Mathes
CERF-CURTIS

CERFnet customer

CIDR: 207.252.219.0/24
IP Range: 207.252.219.0 - 207.252.219.255
Block size: 256

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United States CERFnet Chicago ISDN Subnet
CERF-CHIISDN

CIDR: 207.252.241.0/24
IP Range: 207.252.241.0 - 207.252.241.255
Block size: 256

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United States Merrill Lynch
CERF-ML-C

CIDR: 199.105.255.0/24
IP Range: 199.105.255.0 - 199.105.255.255
Block size: 256

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United States CERFnet San Diego ISDN Testing
CERF-ISDNCERF

CIDR: 199.106.61.0/24
IP Range: 199.106.61.0 - 199.106.61.255
Block size: 256

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United States CERFnet 800-SBA ISDN Network
CERF-800SBA

CIDR: 199.106.77.0/24
IP Range: 199.106.77.0 - 199.106.77.255
Block size: 256

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United States CERFnet
CERF-ISDN2

CIDR: 199.106.78.0/24
IP Range: 199.106.78.0 - 199.106.78.255
Block size: 256

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United States CERFnet San Diego ISDN SBA
CERF-SDSBA

CIDR: 199.106.79.0/24
IP Range: 199.106.79.0 - 199.106.79.255
Block size: 256

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United States Tim Arland
CERF-TCA

CERFnet customer

CIDR: 199.106.199.0/24
IP Range: 199.106.199.0 - 199.106.199.255
Block size: 256

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United States CERFnet Irvine ISDN SBA
CERF-UCISBA

CIDR: 199.107.234.0/24
IP Range: 199.107.234.0 - 199.107.234.255
Block size: 256

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United States CERFnet Pasadena ISDN Subnet
CERF-CITISDN

CIDR: 199.107.235.0/24
IP Range: 199.107.235.0 - 199.107.235.255
Block size: 256

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United States CERFnet San Jose ISDN Subnet
CERF-SJISDN

CIDR: 199.108.60.0/24
IP Range: 199.108.60.0 - 199.108.60.255
Block size: 256

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United States CERFnet Oakland ISDN Subnet
CERF-OAKISDN

CIDR: 199.108.61.0/24
IP Range: 199.108.61.0 - 199.108.61.255
Block size: 256

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United States CERFnet San Jose ISDN Subnet
CERF-SJISDNSUB

CIDR: 199.108.62.0/24
IP Range: 199.108.62.0 - 199.108.62.255
Block size: 256

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United States CERFnet ISDN Diagnostics
CERF-IDIAG

CIDR: 199.108.65.0/24
IP Range: 199.108.65.0 - 199.108.65.255
Block size: 256

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United States CERFnet San Jose ISDN SBA
CERF-SJISDNSBA

CIDR: 199.108.79.0/24
IP Range: 199.108.79.0 - 199.108.79.255
Block size: 256

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United States CERFnet
PASADENA

CIDR: 198.137.140.0/24
IP Range: 198.137.140.0 - 198.137.140.255
Block size: 256

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United States IDC MIA1 CI - Customer Internet
ATTWH-63-240-237-0-24-1511040615

CIDR: 63.240.237.0/24
IP Range: 63.240.237.0 - 63.240.237.255
Block size: 256

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United States CERFnet Los Angeles ISDN Subnet
CERF-LAISDN

CIDR: 206.16.90.0/24
IP Range: 206.16.90.0 - 206.16.90.255
Block size: 256

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Canada CERFnet Customer
CERF-HRL

Hughes Research Labs

CIDR: 206.17.46.0/24
IP Range: 206.17.46.0 - 206.17.46.255
Block size: 256

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United States CERFnet Los Angeles ISDN SBA
CERF-SBAISDN2

CIDR: 206.17.76.0/24
IP Range: 206.17.76.0 - 206.17.76.255
Block size: 256

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United States CERFnet Los Angeles ISDN SBA
CERF-SBAISDN

CIDR: 206.17.79.0/24
IP Range: 206.17.79.0 - 206.17.79.255
Block size: 256

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United States Time-Warner Cable Broadband Applications
CERF-TIMECABLE

CERFnet customer

CIDR: 206.17.180.0/24
IP Range: 206.17.180.0 - 206.17.180.255
Block size: 256

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CIDR: 206.17.250.0/24
IP Range: 206.17.250.0 - 206.17.250.255
Block size: 256

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United States CERFnet
CERF-DSL-SD-A

CIDR: 206.19.8.0/24
IP Range: 206.19.8.0 - 206.19.8.255
Block size: 256

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United States CERFnet Seattle Customer Subnet
CERF-SEATTLESUB

CIDR: 206.19.216.0/24
IP Range: 206.19.216.0 - 206.19.216.255
Block size: 256

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CIDR: 12.37.32.128/25
IP Range: 12.37.32.128 - 12.37.32.255
Block size: 128

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United States IDC PHX1 CI - Customer Internet
ATTWH-199-106-152-128-25-1002134032

CIDR: 199.106.152.128/25
IP Range: 199.106.152.128 - 199.106.152.255
Block size: 128

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United States ICDS-Management Node-Koll
ATTENS-SAN2-006839-1

CIDR: N/A
IP Range: 63.241.13.160 - 63.241.13.255
Block size: 96

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United States Parker Hannifin
ATTENS-007501-001924

CIDR: 199.106.243.0/26
IP Range: 199.106.243.0 - 199.106.243.63
Block size: 64

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United States Security Broadband
ATTENS-007963-000122

CIDR: 199.107.121.64/26
IP Range: 199.107.121.64 - 199.107.121.127
Block size: 64

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United States ICDS-Management Node-Koll
ATTWH-63-241-3-192-26-0809151239

Sid

CIDR: 63.241.3.192/26
IP Range: 63.241.3.192 - 63.241.3.255
Block size: 64

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United States Art Technology Group Inc Annapolis Infrastructure
ATTWH-206-16-11-192-26-1503100633

CIDR: 206.16.11.192/26
IP Range: 206.16.11.192 - 206.16.11.255
Block size: 64

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United States Lithia Springs-GA DC Infrastructure
ATTENS-007033-003458

CIDR: 12.129.67.96/27
IP Range: 12.129.67.96 - 12.129.67.127
Block size: 32

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CIDR: 12.129.203.192/27
IP Range: 12.129.203.192 - 12.129.203.223
Block size: 32

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United States IDC SEA1 CI - Customer Internet
ATTWH-134-24-217-0-27-1802223053

CIDR: 134.24.217.0/27
IP Range: 134.24.217.0 - 134.24.217.31
Block size: 32

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United States ICD Node-SD-Koll
ATTENS-SAN2-006913

CIDR: 63.241.10.32/27
IP Range: 63.241.10.32 - 63.241.10.63
Block size: 32

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United States Stanley Associates
ATTWH-206-16-224-96-27-1004283851

Sid

CIDR: 206.16.224.96/27
IP Range: 206.16.224.96 - 206.16.224.127
Block size: 32

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United States Dixie Numeric
CERF-DIXIENUMERIC

CIDR: 209.187.238.176/28
IP Range: 209.187.238.176 - 209.187.238.191
Block size: 16

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United States Merrill Lynch
CERF-MERRILL-C

CIDR: 199.105.173.208/28
IP Range: 199.105.173.208 - 199.105.173.223
Block size: 16

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United States Kelly Broadcasting
CERF-KELLYBROADCAST

CIDR: 199.105.252.176/28
IP Range: 199.105.252.176 - 199.105.252.191
Block size: 16

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United States IDC PHX1 CI - Customer Internet
ATTWH-199-106-154-0-28-1601075657

CIDR: 199.106.154.0/28
IP Range: 199.106.154.0 - 199.106.154.15
Block size: 16

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United States IDC BOS1 CI - Customer Internet
ATTWH-199-107-225-16-28-0912101334

CIDR: 199.107.225.16/28
IP Range: 199.107.225.16 - 199.107.225.31
Block size: 16

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United States IDC BOS1 CI - Customer Internet
ATTWH-199-107-225-32-28-1506305047

CIDR: 199.107.225.32/28
IP Range: 199.107.225.32 - 199.107.225.47
Block size: 16

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United States ICD NYC 811 Node
ATTENS-NYC2-006969-1

CIDR: 63.240.54.128/28
IP Range: 63.240.54.128 - 63.240.54.143
Block size: 16

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United States ICD Lisle ILL Node
ATTENS-CHI1-006968-1

CIDR: 63.240.133.48/28
IP Range: 63.240.133.48 - 63.240.133.63
Block size: 16

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United States ICD Lisle ILL Node
ATTENS-CHI1-006968-2

CIDR: 63.240.133.64/28
IP Range: 63.240.133.64 - 63.240.133.79
Block size: 16

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United States ICD Lisle ILL Node
ATTENS-006968-005643

CIDR: 63.240.170.160/28
IP Range: 63.240.170.160 - 63.240.170.175
Block size: 16

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United States ICD Node-SD-Koll
ATTENS-006913-005076

CIDR: 63.241.59.32/28
IP Range: 63.241.59.32 - 63.241.59.47
Block size: 16

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United States ICD Node Mesa
ATTENS-PHX1-006934

CIDR: 63.241.135.128/28
IP Range: 63.241.135.128 - 63.241.135.143
Block size: 16

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United States City National Bank Dsl-Mel Quan
ATTWH-206-17-168-224-28-1406110319

Sid

CIDR: 206.17.168.224/28
IP Range: 206.17.168.224 - 206.17.168.239
Block size: 16

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United States Karl Schmidt
ATTENS-DETROIT-007075

CIDR: 206.18.136.128/28
IP Range: 206.18.136.128 - 206.18.136.143
Block size: 16

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