An obstruction of the HPWREN link by a sizable object

3 May 2024

One of the recently constructed UCSD campus buildings has encroached upon the path of the HPWREN link between Mount Soledad and the San Diego Supercomputer Center, particularly building four of the newly established Theater District Living and Learning Neighborhood (TDLLN) on the UCSD campus. Consequently, a new wireless link has been necessitated, extending from the campus's tallest structure to the HPWREN site on Mount Soledad. This link constitutes a portion of a high-bandwidth 10 Gb/s backup path interconnecting data centers at SDSC and SIO, in addition to providing a resilient route into the larger wireless backbone via Mount Soledad. Furthermore, it presented an opportunity to incorporate HPWREN and ALERTCalifornia cameras onto that rooftop.

The link comprises two components - a dark fiber segment extending from SDSC to TDLLN, and an 80 GHz millimeter-wave radio link extending from TDLLN to MS.

A newly installed router at TDLLN facilitates connectivity to cameras collocated atop the building. These cameras offer views into the Rose Canyon region of San Diego, a significant urban/wildlife boundary zone encompassing two freeways, railroad tracks, power lines, residential dwellings, and natural parkland.

As an integral part of HPWREN's MPLS-enabled backbone, the new link enables HPWREN to furnish wireless backup connectivity for researchers at SIO in the event of damage to the primary fiber optic path between SIO and the main campus.

An identical radio pair extends from the Scripps library (Eckhart Building) to Mount Soledad. A dedicated 40 gbps fiber connects SIO to SDSC, thereby creating a combined optical and fiber loop from SDSC to MS, then back to SDSC via SIO.

Indoor equipment at the TDLLN building
Outside equipment, showing the dish antenna for the link to Mount Soledad, with a pair of HPWREN camera sets and an ALERTCalifornia pan/tilt/zoom camera above
Closeup view of the camera set near the south end of the building. Images taken by the cameras are publicly available at