AS10867 FHDA-AS

FHDA-AS is the Foothill-DeAnza Community College District, the two-campus public community college district in California's Santa Clara County that operates Foothill College in Los Altos Hills and De Anza College in Cupertino.

What it's used for

Campus networking for the district. RIS shows 3 announced IPv4 prefixes carrying 65,536 addresses and 1 observed BGP neighbour, with no IPv6 in the routing table. The prefixes are 153.18.0.0/16 plus its two covering halves, 153.18.0.0/17 and 153.18.128.0/17, which is the classic shape of a single legacy Class B being announced both as a whole and split for traffic engineering or multi-site separation between the two campuses.

The single observed neighbour is the tell for role. This is an edge network with one upstream, almost certainly reached through California's regional research and education networking, not a network that sells transit or peers widely. Everything about the footprint says an institution announcing its own campus space: faculty and staff workstations, lab and classroom networks, student wireless, and the district's own servers.

Notable

Sixty-five thousand addresses for a two-college district is enormous by modern standards, and it is a straightforward artifact of when the block was assigned. A /16 was an ordinary allocation for a university or district in the pre-CIDR era; nobody would issue one today.

Interesting

The district sits in the geographic heart of Silicon Valley, with De Anza College roughly across the road from Apple's Cupertino campus.