AS11188 LACOUNTY-ISD

LACOUNTY-ISD is the Internal Services Department of the County of Los Angeles — the county's central IT and telecom organisation. It runs the shared network that the county's departments sit behind.

What it's used for

County government networking at genuine scale. RIS observes 49 IPv4 prefixes and roughly 132,352 addresses, anchored on two /16s: 159.83.0.0/16 and 170.208.0.0/16. There is no IPv6 in the observed routing. Only five BGP neighbours are seen, which is the shape of a large end-user network buying transit, not a carrier — the address count is big, the peering is not.

The registrant data confirms the AS is announcing its own county space rather than anyone else's: the two /16s are registered to LANET and LANET-1, and the long tail of /24s deaggregated out of them carries the same handles. One block, 159.225.155.0/24, is registered separately to LADHS-GOV — Los Angeles County's Department of Health Services, an agency inside the same county, which is exactly what you would expect a shared county AS to carry.

Notable

Los Angeles County is the largest county in the United States by population, and the address footprint reflects that: sheriff, health services, courts-adjacent systems, public works and dozens of other departments are all customers of this one network organisation.

Interesting

Almost the whole prefix list is /24s carved out of the two supernets and announced alongside them. That deaggregation is typical of a network stitching many departmental sites together over multiple upstream circuits.