Power And Communications

Presented at 1995 MK Users' Committee Meeting

I. Agreement with GTE Hawaiian Tel


The Institute for Astronomy has recently entered into a 10-year Network Service Agreement with GTE Hawaiian Tel (GTE) to provide high-bandwidth communications for the Mauna Kea Observatories. The initial implementation will comprise two SONET rings. An OC-12 (622 Mbps) ring will connect all facilities on the summit, the Mid-Level Facility, and the junction node at the base of Mauna Kea at Humuula (see Fig. A). A second SONET ring with an OC-48 (2.4 Gbps) capacity will connect Humuula with Hilo and Kamuela, where the telescope base facilities are located. GTE will install fiber optic cable on existing HELCO poles between Humuula and the HELCO substation at Hale Pohaku. At the substation, the fiber will go underground to the Mid-Level Facility, where it will connect to Hawaiian Tel's existing fiber cable to the summit.

GTE has chosen SONET to provide the basic infrastructure using proven technology capable of transporting high-bandwidth services for the Observatories. SONET will not only be able to accommodate existing demands for service, but more importantly, will be suitable as the physical transport for emerging services, such as ATM. The standards for the latter are still being finalized, especially for WAN routing. During the initial phase, only point-to-point leased services are anticipated with their monthly recurring cost subsidized by the Observatories' initial infrastructure contribution. Because of this and the fact that bandwidth contention is not an issue during the initial phase, the benefits of ATM would not be appreciable.


The system will provide the Mauna Kea Observatories with 11.5 DS-3 (45 Mbps) circuits on each of the two SONET rings. Hawaiian Tel will use the remaining 0.5 DS-3 in the OC-12 trunk for voice circuits. Fiber cable installations from Hawaiian Tel splice points (usually a manhole close to the facility) to the observatories/bases will be established under separate agreements with the individual observatories. These agreements will contain a monthly recurring charge, but no installation charge. The monthly recurring cost will be based on the cost of the fiber cable installations at each facility, plus the cost of the fiber optic terminals and equipment required by the service requested. The monthly recurring charges for observatories using the initial 11.5 DS-3 intra-island transport will be less than $3,000 for DS-3 service and tariffed rates or less for DS-1 service.

IfA will assume responsibility for bandwidth allocation on the 11.5 DS-3; each facility will initially be allocated one DS-3. Additional circuits beyond the 11.5 DS-3 with bandwidth up to 3 OC-12 would be available at normal market rates. Once the voice circuits have been transferred to the fiber, the existing microwave radio at the summit will be deactivated.


Currently GTE Hawaiian Tel is pursuing Public Utilities Commission approval for the Network Service Agreement. IfA is moving ahead with the permitting of the fiber link between Hale Pohaku and Humuula. It is also proceeding with the renovation of the Utility Building at the summit, which will house both the IfA and Hawaiian Tel fiber optic equipment. The installation of new underground ducts at Hale Pohaku and the overhead fiber optic line from Humuula to the Hale Pohaku HELCO substation is expected to take place early in 1996.

II. Infrastructure Improvements


Infrastructure improvements are needed both at the summit and at Hale Pohaku to provide adequate electrical and communication services to the Observatories. At the summit, an overall doubling of the electrical distribution capacity is required, together with extension of service to the SMA site. For communications at the summit, an expansion of the duct system is necessary both to reach the SMA and to provide new and expanded services for all facilities. The basic communications requirements are:

  1. GTE Hawaiian Tel copper cable for telephone (voice) service (25+ pairs/facility)
  2. GTE Hawaiian Tel fiber optic cable for high-bandwidth wide area communications (new).
  3. Fiber optic cable for the Mauna Kea Observatories local area network, which extends around the summit and to Hale Pohaku (minimum 6 pairs of fibers/facility)

The summit upgrade has been divided into two phases, the first of which was completed in July by the Gemini project and the second of which will be carried out next summer in conjunction with the SMA. The improvements at Hale Pohaku are relatively minor consisting of an extension of the communication ducts from the Mid-Level Facility down to the HELCO substation.

Summit Ridge Improvements by Gemini

Gemini has completed the following utility infrastructure improvements along the summit ridge:

  1. New 5-inch electrical ducts and cabling have been installed from handhole (HH) 12 near the Utility Building to HH 16 near CFHT. Electrical power to CFHT, IRTF, Keck and Subaru has been rerouted to the new cabling.
  2. Four new 4-inch communication ducts have been installed along the same route. One duct contains GTE Hawaiian Tel's copper cable for telephone service. A second contains a single new fiber sheath containing 32 fibers which was pulled from the Utility Building to HH 16 at CFHT. These fibers were spliced one-by-one to the existing MKO Communications Network fibers leading to CFHT, IRTF, Keck and Subaru. The average length of service interruption to complete the rerouting of the Mauna Kea Observatories Communications Network was two hours per facility.
  3. During this work, a number of faulty fibers were respliced and a new rack with fiber optic distribution panels was installed in the Utility Building. The rack is needed to accommodate future expansion of the network, including any transitional work required. The existing fiber optic distribution panels were relocated to the new rack.

Closing the Loop

The second phase of the improvements includes:

  1. Extending the power and communication distribution system from HH 25 at Subaru to a new HH 26 at the SMA and then on to link up with the existing system at HH 27 near JCMT.
  2. Two new PME-9 switches near HH 26 and extension of the primary electrical feeders from the existing switches at HH 34 to the new switches. This will double the capacity of the summit distribution system.
  3. Installation of a fiber-optic trunk cable and a new copper trunk cable by GTE Hawaiian Tel.
  4. Replacement of the existing Mauna Kea Network fiber optic cables with a trunk cable which will provide at least 6 fiber pairs for each facility. At a handhole near each facility, the individual trunk fibers will be field spliced to a fiber cable leading to the facility patch panel.

These improvements have been planned so that there will be at most very minor interruptions in voice and data service during the installation.

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