Sign inMonitor a domain
AS6128

AS6128 is Optimum (Altice USA)’s network.

Last updated 3 Nov 2026 from DB-IP ASN Lite (2026-11-01) and RIR statistics (3 Nov 2026)

Short answer

AS6128 belongs to Cablevision Systems Corp.. DB-IP Lite attributes 4,864,768 IPv4 addresses in 118 ranges and 2 IPv6 ranges to it, all or nearly all of the IPv4 space in United States. The number is registered with ARIN in United States.

Facts for AS6128
Operator (DB-IP)Cablevision Systems Corp.
KindHome broadband (curated)
IPv4 addresses4,864,768
IPv4 ranges118
IPv6 ranges2
RegistryARIN
Registered—
Registry countryUnited States (US)

Does it publish a geofeed?

Not for the range we sampled (24.184.0.0 – 24.191.255.255): its registry record, and the record above it, link no RFC 8805 geofeed (checked 2 Nov 2026). Without one, location databases have to estimate where these addresses are used, which is a common reason customers of Optimum (Altice USA) see the wrong city. Customers can ask Optimum (Altice USA) to publish one; the evidence report drafts that request.

Shared addresses (CGNAT)

Optimum (Altice USA) hasn’t been documented as using carrier-grade NAT in a source we could check. To see whether your own connection is behind it, compare your router’s address on the CGNAT check.

IPv6

DB-IP lists 2 IPv6 ranges for AS6128, so customers can get IPv6 addresses, which databases place separately from IPv4.

Where its IPv4 space is used, according to DB-IP

US100%
DE0.01%

Share of the network’s IPv4 addresses by DB-IP Country Lite. IP Geolocation by DB-IP.

IP ranges

RangeAs CIDRAddresses
24.38.0.0 – 24.38.3.25524.38.0.0/221,024
24.38.5.0 – 24.38.9.25524.38.5.0/24, 24.38.6.0/23 …1,280
24.38.11.0 – 24.38.19.25524.38.11.0/24, 24.38.12.0/22 …2,304
24.38.22.0 – 24.38.24.25524.38.22.0/23, 24.38.24.0/24768
24.38.26.0 – 24.38.32.25524.38.26.0/23, 24.38.28.0/22 …1,792
24.38.34.0 – 24.38.36.25524.38.34.0/23, 24.38.36.0/24768
24.38.38.0 – 24.38.38.25524.38.38.0/24256
24.38.41.0 – 24.38.73.25524.38.41.0/24, 24.38.42.0/23 …8,448
24.38.75.0 – 24.38.81.25524.38.75.0/24, 24.38.76.0/22 …1,792
24.38.83.0 – 24.38.85.25524.38.83.0/24, 24.38.84.0/23768
24.38.87.0 – 24.38.89.25524.38.87.0/24, 24.38.88.0/23768
24.38.91.0 – 24.38.92.25524.38.91.0/24, 24.38.92.0/24512
24.38.94.0 – 24.38.96.25524.38.94.0/23, 24.38.96.0/24768
24.38.98.0 – 24.38.99.25524.38.98.0/23512
24.38.101.0 – 24.38.101.25524.38.101.0/24256
24.38.103.0 – 24.38.108.25524.38.103.0/24, 24.38.104.0/22 …1,536
24.38.110.0 – 24.38.124.25524.38.110.0/23, 24.38.112.0/21 …3,840
24.38.126.0 – 24.38.127.25524.38.126.0/23512
24.38.192.0 – 24.38.255.25524.38.192.0/1816,384
24.44.0.0 – 24.47.255.25524.44.0.0/14262,144
24.55.131.0 – 24.55.132.25524.55.131.0/24, 24.55.132.0/24512
24.89.128.0 – 24.89.191.25524.89.128.0/1816,384
24.146.128.0 – 24.146.255.25524.146.128.0/1732,768
24.157.32.0 – 24.157.32.25524.157.32.0/24256
24.157.35.0 – 24.157.43.25524.157.35.0/24, 24.157.36.0/22 …2,304
24.157.45.0 – 24.157.46.25524.157.45.0/24, 24.157.46.0/24512
24.157.48.0 – 24.157.52.25524.157.48.0/22, 24.157.52.0/241,280
24.157.54.0 – 24.157.63.25524.157.54.0/23, 24.157.56.0/212,560
24.184.0.0 – 24.191.255.25524.184.0.0/13524,288
24.228.0.0 – 24.228.255.25524.228.0.0/1665,536
24.229.16.0 – 24.229.17.25524.229.16.0/23512
24.229.32.0 – 24.229.32.25524.229.32.0/24256
24.229.41.0 – 24.229.41.25524.229.41.0/24256
24.229.55.0 – 24.229.55.25524.229.55.0/24256
24.229.76.0 – 24.229.76.25524.229.76.0/24256
24.246.96.0 – 24.246.104.25524.246.96.0/21, 24.246.104.0/242,304
24.246.106.0 – 24.246.106.25524.246.106.0/24256
24.246.108.0 – 24.246.113.25524.246.108.0/22, 24.246.112.0/231,536
24.246.115.0 – 24.246.125.25524.246.115.0/24, 24.246.116.0/22 …2,816
24.246.127.0 – 24.246.127.25524.246.127.0/24256
47.16.0.0 – 47.18.255.25547.16.0.0/15, 47.18.0.0/16196,608
47.20.0.0 – 47.23.255.25547.20.0.0/14262,144
50.29.0.0 – 50.29.127.25550.29.0.0/1732,768
63.142.20.0 – 63.142.20.25563.142.20.0/24256
63.247.160.0 – 63.247.165.25563.247.160.0/22, 63.247.164.0/231,536
63.247.167.0 – 63.247.188.25563.247.167.0/24, 63.247.168.0/21 …5,632
63.247.190.0 – 63.247.191.25563.247.190.0/23512
64.15.0.0 – 64.15.15.25564.15.0.0/204,096
64.15.18.0 – 64.15.19.25564.15.18.0/23512
64.15.21.0 – 64.15.21.25564.15.21.0/24256
2600:4800:: – 2600:480f:ffff:ffff:ffff:ffff:ffff:ffff2600:4800::/28IPv6
2602:230:: – 2602:230:ffff:ffff:ffff:ffff:ffff:ffff2602:230::/32IPv6
Showing 50 of 118 IPv4 and 2 of 2 IPv6 ranges All ranges (CSV)

IP Geolocation by DB-IP, ASN Lite, CC BY 4.0.

Using an address from this network? See which sources agree on where it is.

Sources

  1. DB-IP IP to ASN Lite (CC BY 4.0) · checked 3 Nov 2026
  2. NRO RIR delegated-extended statistics · checked 4 Nov 2026