The computing facilities available to students and researchers at the HCII include the User Studies Labs, experimental computers, and a wide variety of networked machines.

Heterogeneous Distributed Computing
The School of Computer Science (SCS) research facility has a wide variety of computers available for faculty and graduate student use -- more than 1800 machines. Nearly every person in the SCS has the individual use of a workstation. Centralized facilities include 40 time-shared machines, most of which run the Mach operating system, a 4.3BSD UNIX variant developed for distributed parallel processing. Personal computing employs various DEC workstations, IBMs, Suns, and several other machines, most of which can also run Mach. Apollo workstations are represented here, as well as HP, Silicon Graphics and NeXT machines. All have transparent access to the Andrew File System, a very large, shared file space, and to one another through Remote File System access. The total disk space within SCS and the Robotics Institute is greater than 600 gigabytes. There are a few VMS systems as well, used in support of special projects. Beyond these resources, the University maintains computation facilities of various kinds for general use.

The Carnegie Mellon Internet is a fully-interconnected, multimedia, multiprotocol infrastructure spanning over 100 segments. These segments are attached to an "inverted" backbone, enabling access between all systems on the campus, including the Cray facilities operated by the Pittsburgh Supercomputing Center. Media and lowest-level protocols include Ethernet, IBM Token Ring, PhoneNet, and fiber optics. Communications use various protocol standards, including AppleTalk and the DoD IP/TCP. Separate network spurs are used for experimentation. Carnegie Mellon is a primary node of the Defense Research Internet (providing national and international network connections), the NSFnet, SURAnet, and PREPnet. As part of a joint venture with Bell of Pennsylvania, SCS is establishing a Wide-Area Network (WAN) telecommuting infrastructure. Using synchronous 64 Kbaud pipes provided via Data-Over-Voice (DOV) links, campus Ethernet network connections are made available in the homes of department students, staff, and faculty at low cost. Research under- way here will allow making these connections anywhere in the 412-LATA (Local-Area Telephone Access) region serving Carnegie Mellon and will expand the connection bandwidth by an order of magnitude.