What Is Binary Synchronous Communication (Bisync)? - ITU Online

What Is Binary Synchronous Communication (Bisync)?

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Definition: Binary Synchronous Communication

Binary Synchronous Communication (Bisync) is a data communication protocol designed by IBM in the 1960s. It is a character-oriented protocol, meaning it operates by sending and receiving fixed-length blocks of characters. Bisync uses synchronous transmission, requiring both the sending and receiving devices to be synchronized with each other’s clocks to accurately transmit and receive data. This protocol was widely used for early computer communications, including banking systems, airline reservations, and various types of business and administrative systems.

Bisync’s operation is based on a handshake process between the sender and receiver. The sender initiates communication by sending a SYN (synchronization) character, ensuring that both devices are in sync. Data is then transmitted in frames, which are blocks of data bracketed by control characters, including the start of the header, address, and end of transmission blocks. Error checking is typically performed using parity bits or cyclic redundancy checks (CRC) to ensure data integrity.

Expanding on Binary Synchronous Communication

Bisync protocol was a cornerstone in the development of data communication technologies. It paved the way for more advanced protocols by establishing a foundation for synchronous data transfer, where timing is essential for the accurate reception of transmitted information. In this framework, data integrity and error correction were pivotal components, addressing the challenges of early digital communications over less reliable mediums.

Key Features and Functions

  • Synchronous Transmission: Bisync relies on a synchronized communication channel, where both the sender and receiver operate under a shared timing signal. This synchronization ensures that the receiver can accurately interpret the timing of bit transmission, crucial for decoding the received data.
  • Error Detection and Correction: The protocol incorporates mechanisms for detecting and correcting errors in transmitted data, such as parity bits and cyclic redundancy checks (CRC). These features are vital for maintaining data integrity across potentially noisy communication lines.
  • Control Characters and Framing: Bisync uses special control characters to frame data packets, delineate messages, and control the flow of communication. These characters include SYN for synchronization, STX (start of text), and ETX (end of text), among others.
  • Handshake Process: A handshake mechanism is employed to establish and terminate communication sessions. This process ensures that both the sender and receiver are ready for data exchange, enhancing the protocol’s reliability.

Historical Importance and Evolution

Originally, Bisync was a pioneering solution for the challenges of early computer communications, offering a structured method for data exchange over telecommunication lines. Its implementation across various industries showcased the feasibility and importance of computer networks. However, as technology advanced, more efficient and flexible protocols were developed. Today, while Bisync is largely considered obsolete, its legacy lives on in the principles it established, which have been refined and expanded in subsequent data communication protocols.

Applications and Legacy

Although Bisync’s direct usage has waned, its conceptual framework influenced the development of subsequent protocols. In industries like banking, aviation, and telecommunications, Bisync laid the groundwork for the standardized, reliable exchange of information. Its emphasis on synchronization, error handling, and data framing can be seen in modern protocols that support today’s internet and communication networks.

Frequently Asked Questions Related to Binary Synchronous Communication

What is Binary Synchronous Communication?

Binary Synchronous Communication (Bisync) is a data communication protocol developed by IBM in the 1960s, characterized by synchronous data transmission and the use of control characters for framing and error checking.

How does Bisync ensure data integrity?

Bisync ensures data integrity through error detection and correction mechanisms, such as parity bits and cyclic redundancy checks (CRC), to identify and correct errors in the transmitted data.

What are the key features of the Bisync protocol?

Key features include synchronous transmission, control characters for data framing, error detection and correction, and a handshake process for initiating and terminating communication sessions.

Why is synchronization important in Bisync?

Synchronization is crucial for ensuring that the sender and receiver are aligned in their timing, allowing for the accurate interpretation and reconstruction of the transmitted data.

What has replaced Binary Synchronous Communication in modern networks?

Modern networks have largely moved to more flexible and efficient protocols, such as TCP/IP, which support a wider range of applications and data types over the internet.

How did Bisync impact the development of subsequent communication protocols?

Bisync’s emphasis on synchronization, error handling, and structured data framing influenced the design and functionality of later protocols, laying the groundwork for the advanced communication systems we use today.

Can Bisync be used over modern digital networks?

While theoretically possible, Bisync is not designed for modern digital networks and lacks the flexibility and efficiency of contemporary protocols designed for internet and digital communication.

What industries heavily relied on Bisync for communication?

Banking, aviation, and telecommunications were among the industries that heavily relied on Bisync for secure and reliable data communication in its early days.

Is Bisync still in use today?

Although Bisync is largely obsolete, certain legacy systems in specific industries may still use it for specific, niche applications where modern alternatives are not feasible or where legacy systems have not been updated.

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