Here is a small selection of institutions and companies we are associated with. 
ACOnet's participating organizations can be found in the List of Participants.

A1 Telekom Austria - Backbone Provider

ACOmarket - IT Service Broker for Austrian Universities

ASC - Austrian Scientific Computing (formerly: VSC - Vienna Scientific Cluster)

BIRD - Open Source Route Server Software

CERT.at - Computer Emergency Response Team Austria

GÉANT - Pan-European Research and Education Network

Hurricane Electric - Upstream Provider

ISPA - Internet Service Providers Austria

next layer - Upstream Provider

nic.at - Austrian Domain Registry

Nokia - Switches & Routers

NTS - Service & Support

PHAIDRA - Digital Asset Management System

RIPE NCC - RIPE Network Coordination Centre

Stopline - Report Centre against Illegal Content on the Internet

University of Vienna - Legal Entity and Operator of ACOnet

VIX - Vienna Internet eXchange