AS11891 City of San Leandro

COSL-ASN-01 - City of San Leandro · registered in the United States

IPv4 addresses2561 prefixes · <0.001% of announced IPv4

Rank in United States#13,844largest network in US by IPv4 space, of 18,338 · <0.01% of US

Rank worldwide#63,355of 79,396 networks with IPv4

IPv6noneno IPv6 routes announced

CountryUnited States18,679 ASNs registered there

Open AS11891 in ASN lookup Look up an IP in this network (12.21.101.1) All networks in United States

IPv4 prefixes

All 1 prefix, in address order.

12.21.101.0/24

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AS11916#13847 UNDP - UNDP256

IP-to-ASN data: iptoasn.com (public domain). Snapshot downloaded 2026-11-11, refreshed daily. Ranges are what each network announces in BGP, not registry allocations. Data sources