JITC Battlespace Awareness / JTC COMMON DATA LINK Compliance Verification Interoperability Test & Evaluation Web Site

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CDL Test Bed

The CDL Test Bed located at JITC is equipped with the appropriate CDL test tools and personnel to provide CDL Waveform Specification Compliance Testing and Verification. CDL vendors are charged a standard rate using a Standard Rate Schedule. This fee helps pay for the costs of the test, and includes maintenance and operation of the CDL Test Bed.

    The Test Bed provides:

• Greater access to test equipment by allowing developers and program managers access to the facility.
• Better cost effectiveness by allowing program managers and developers to share the testing costs.
• Resources for JITC to perform as airborne reconnaissance community independent waveform tester.
• Confidence for PM's and services that the data link has demonstrated a specific level of interoperability with legacy CDL equipment.

Compliance Verification and Interoperability Testing

CDL legacy, migration, and future implementations are tested and verified in accordance with CJCSI 6212.01E. As a precursor to the interoperability test, a compliance verification test is performed. The objective of this test is to determine the degree of compliance to the CDL specification. CDL Systems need to accomplish as a minimum the following:

• Verify CDL is Compliant with Relevant CDL Specifications
• Certify Interoperability is Relevant to CJCSI 6212.01E

JITC conducts CDL compliance verification tests as laboratory tests. An RF cable connection between the system under test (SUT) and an external CDL PCE/SCE is used instead of an over-the-air RF transmission from antenna to antenna. The SUT is tested in the operational X / Ku band frequency ranges and at operational data rates but is not tested with sensor or processor interfaces. JITC can conduct the test in conjunction with developmental test events or can plan and conduct the test as a JITC-only test event.

Laboratory testing does not measure:

• Accuracy of the SND, antenna tracking, and Ranging. SND, antenna tracking, and Ranging are verified during operational tests or demonstrations
• FL/RL phase and amplitude. Vendor provides the CDL PM with verification that the FL/RL phase and amplitude imbalance meet the specification criteria.

JITC will use compliance verified CDL equipment, compliance validated CDL equipment tested by JITC with CDL systems that have demonstrated CDL compliance through operational or test bed use, or CDL test systems. These equipment and systems include but are not limited to the following CDL systems:

• Modularized Interoperability Surface Terminal (MIST), at L3 Communications
• Common Imagery Ground/Surface System (CIGSS) Test Bed
• Common High Bandwidth Data Link-Surface Terminal (CHBDL-ST), at L3 Communications
• Portable Ground Support Equipment (PGSE)
• CDL Functional Tester (CDL-FT)
• CDL Test Terminals (under development)
• CDL Test Set (not under contract)

Based on test results, analysts determine if the system complies with the Waveform Specification for the CDL Segment, Specification. Where anomalies occur, analysts attempt to determine the operational impact.

JITC uses synchronization (SYNC) indicators to determine if specific digital processes are correctly operating. If SYNC indicators are not available on the SUT then JITC infers from a successfully established data link that specific digital processes are correctly operating. JITC conducts the compliance verification test in the following four phases:

• Phase 1. Modulation Off. Frequency counter used to measure accuracy of FL/RL frequencies (carrier frequency uncertainty) and spectrum analyzer used to measure center frequency signal and spurious signals or in-band interference.
• Phase 2. Modulation On. External PCE/SCE connected to the SUT by RF cable to provide functional capabilities needed to test SUT. JITC observes and records data from the operator control display to verify FL/RL X and Ku band frequencies, and FL/RL data rates. JITC observes, times, and records data from the SUT synchronization indicators to determine if the SUT performs the interleave/de-interleave, encode/decode, multiplex/de-multiplex, and EFC/ EFD IDL and MIDL frame format functions. JITC observes, times, and records data to determine if FL/RL frequency change commands are executed and Pseudo-random Noise (PN) codes are resolved within the specified time criteria. JITC uses BER test sets to measure BER on the SUT channels and ATM/Ethernet test sets to verify network functions. JITC uses headsets with microphones connected to the SUT to test audio (voice) quality of the full-duplex link.
• Phase 3. Encryption/Decryption. JITC observes and records data during COMSEC power interrupt and bypass test to evaluate cryptographic key retention and the COMSEC bypass function. JITC uses BER test sets to measure encrypted BER.
• Phase 4. SND. External navigational simulator used to provide SND.

CDL Verification Process

The CDL verification process is initiated at the request of a Program Manager (PM) or Vendor and is based on the CDL Waveform Specification criteria. The CDL Team coordinates the following:

• Assist Program Managers throughout the life cycle with System Development and Achieving DOD/OSD Interoperability Goals.
• Review requirements documents, test plans and test reports
• Coordinate test requirements and test opportunities with PMs, testers, developers, vendors, and user representatives as appropriate.
• Develop and coordinate test plans to ensure specification/standards compliance and interoperability requirements are fully integrated with CDL test events.
• Conduct specification/standards compliance and interoperability testing of CDL Migration and Legacy Systems.
• Process test data and present the data in a form consistent with JITC reporting requirements/procedures.

Compliance Verification Letter

JITC issues a CDL Compliance Verification Letter based on a successful compliance test or approved waivers. The Compliance Verification Letter with Test Summary enclosure will be distributed to all concerned. Compliance Verifications are good for three years unless major changes are made to the system. At the end of the three years, a desktop analysis is conducted to determine if retesting is necessary. If not, a letter is issued for another three year period. All Compliance Verification Letters are placed on the JITC CDL Web Page Registry.

CDL Assessment Letter and Test Summary

If the system is not CDL compliant and requires a waiver or retest a JITC CDL Assessment Letter with enclosed Test Summary is issued 30 days after completion of testing. This letter is sent to the PM or Vendor stating the system is not compliant with the CDL Waveform Specification and identifies possible waiver requirements. The PM or Vendor requests a waiver for the non compliant criteria through their service CDL representative, who provides an endorsement or rejection, to the CDL Working Integrated Product Team (WIPT). If the CDL WIPT approves the request for waiver of non compliant criteria an approval letter is forwarded to JITC and JITC changes the compliance assessment to a compliance verification and prepares a Compliance Verification Letter for the PM or Vendor.