AS9321 HYUNET-AS Hanyang University

AS9321 (HYUNET-AS) is held by Hanyang University, a private university in Seoul, South Korea. The ASN carries HYUnet, the university's campus network.

What it's used for

The evidence is that of a single-institution network with a large legacy allocation. RIS sees 17 IPv4 prefixes carrying 65,536 addresses, no IPv6, and just 1 observed BGP neighbour. One neighbour means the campus is effectively single-homed: it buys transit from one Korean upstream and originates nothing but its own space. There is no peering breadth, no downstream customers, and no sign of any commercial role.

The prefix list makes the structure obvious. Hanyang holds the whole of 166.104.0.0/16 and announces it both as the covering /16 and as sixteen /20s that tile the block exactly — 166.104.0.0/20, 166.104.16.0/20, 166.104.32.0/20 and so on through 166.104.240.0/20. A complete, evenly-sized tiling like that is not organic growth; it is a deliberate deaggregation of one allocation, typically done to steer traffic or to keep more specifics reachable if the aggregate is filtered. Everything in the ASN serves one campus: faculty and student access, departmental servers, and university-run services.

Notable

• A full /16 for a single university is a mark of an early allocation, from a period when Korean institutions received far more IPv4 than they would today.
• No IPv6 is announced from this ASN.