Matching ISDN Standards with Interfaces

This question requires matching different types of Integrated Services Digital Network (ISDN) standards with their corresponding interface descriptions. Let's analyze each match based on the provided lists:

1. Match: Basic Rate Interface (BRI) with Interface IV

Basic Rate Interface (BRI) is a fundamental ISDN access standard. It typically offers two 64 kbps bearer channels (B channels) for voice and data, plus one 16 kbps data channel (D channel). This configuration (2B+D) is commonly used for residential and small business customers.

• Matches: A - IV (A standard ISDN interface providing two 64 kbps channels for voice and data transmission)

2. Match: Primary Rate Interface (PRI) with Interface III

Primary Rate Interface (PRI) represents a higher-capacity ISDN service, typically used by larger organizations. In the North American standard, it consists of 23 B channels and one D channel (23B+D), totaling 1.536 Mbps or 1536 kbps. This provides significantly more bandwidth than BRI.

• Matches: B - III (A high-capacity ISDN interface providing 23 B channels plus one 64 kbps D channel for a total of 1536 kbps.)

3. Match: B-ISDN with Interface II

Broadband ISDN (B-ISDN) is an evolution of ISDN designed to support much higher data rates using technologies like Asynchronous Transfer Mode (ATM). It enables services like high-definition video and high-speed data transmission.

• Matches: C - II (An extension of ISDN offering Asynchronous Transfer Mode (ATM))

4. Match: Symmetric DSL Interface (ADSL) and Ultra-Advanced Rate Interface (UARI) with Interface I

ADSL (Asymmetric Digital Subscriber Line) and UARI are broadband technologies that utilize existing telephone lines but are distinct from the standard ISDN interfaces like BRI and PRI. While they offer high-speed data services, they are generally considered separate from the core ISDN standards in classification.

• Matches: D - I (They are not part of ISDN interfaces)

Conclusion

Combining these matches, the correct pairing is A-IV, B-III, C-II, and D-I.

Therefore, the correct option is A-IV, B-III, C-II, D-I.