SCC & CROSS CONNECT BOARD IN DWDM SYSTEM

 In a **DWDM (Dense Wavelength Division Multiplexing)** system, **SCC (System Control & Communication) boards** and **cross-connect boards** play crucial roles in managing and directing optical signals. Here’s a breakdown of their functions:


### **1. SCC (System Control & Communication) Board**

- **Purpose**: Acts as the **brain** of the DWDM system, managing overall system control, monitoring, and communication.

- **Key Functions**:

  - **Supervision & Alarms**: Monitors performance parameters (power levels, wavelengths, temperature) and raises alarms for faults.

  - **Configuration Management**: Controls add/drop multiplexers (OADMs), amplifiers (EDFAs), and other line cards.

  - **Communication Hub**: Facilitates communication between network elements (NEs) and the **Network Management System (NMS)** via protocols like **OSC (Optical Supervisory Channel)**.

  - **Software Updates & Logging**: Handles firmware updates and logs system events.


### **2. Cross-Connect Board (XC Board)**

- **Purpose**: Enables flexible **wavelength routing** and switching within the DWDM system.

- **Key Functions**:

  - **Optical Channel Switching**: Dynamically routes wavelengths between different ports (e.g., from a transponder to an OADM).

  - **Protection Switching**: Supports **1+1 or mesh protection** by rerouting traffic in case of fiber cuts or failures.

  - **ROADM (Reconfigurable OADM) Support**: Allows remote reconfiguration of wavelength paths without manual intervention.

  - **Grid Flexibility**: Supports **fixed or flexible grid** (e.g., 50GHz, 100GHz, or elastic grid for superchannels).


### **Comparison: SCC vs. Cross-Connect Board**

| Feature | **SCC Board** | **Cross-Connect Board** |

|---------|--------------|-------------------------|

| **Role** | System control & monitoring | Wavelength routing & switching |

| **Key Tasks** | Alarm handling, NMS communication, software control | Optical path switching, ROADM support |

| **Dependency** | Required for system operation | Optional (used in advanced DWDM networks) |

| **Interface** | Communicates with all cards via OSC | Connects to transponders, mux/demux, amplifiers |


### **Typical Deployment Scenario**

- The **SCC board** ensures the system is running correctly, while the **cross-connect board** (often part of a **ROADM**) enables dynamic wavelength assignment.

- Example: In a **mesh network**, the XC board allows wavelengths to be rerouted automatically if a fiber fails, while the SCC logs the event and alerts the NMS.


### **Conclusion**

- **SCC** = **Control & Monitoring** (essential for all DWDM systems).

- **Cross-Connect Board** = **Traffic Routing & Flexibility** (critical for ROADM-based )

Comments

Post a Comment

Popular posts from this blog

Alarms in OTN system and explanations

Optical Transport Network (OTN) systems have several alarms to monitor network health and detect issues that could impact performance. These alarms are categorized based on layers (OTU, ODU, and client signals) and types of failures. Here are the key OTN alarms and their explanations: 1. Optical Channel (OTU) Alarms These alarms occur at the Optical Transport Unit (OTU) layer, which ensures error correction and transport. LOF (Loss of Frame): The OTU cannot detect a valid frame alignment. This happens due to signal corruption. LOS (Loss of Signal): No optical signal is detected, often due to fiber cuts or transceiver issues. LOM (Loss of Multiframe): The multiframe alignment is lost, affecting higher-layer multiplexing. OTUk-BDI (Backward Defect Indication): The remote end reports a defect at the OTUk layer, signaling back to the sender. OTUk-SF (Signal Fail): Severe degradation in the signal, triggering protection switching. OTUk-SD (Signal Degrade): The signal is degra...
Read more

OTN frame structure with details

 The **Optical Transport Network (OTN)** framework is defined by the ITU-T G.709 standard, which specifies the structure and functionality of the OTN. OTN is designed to provide a standardized way to transport and manage high-speed data over optical networks. Below is an overview of the OTN frame structure:  **OTN Frame Structure** The OTN frame consists of several layers and overheads, which are organized into a hierarchical structure. The key components of the OTN frame include: 1. **OTUk (Optical Transport Unit, level k):**    - The OTUk is the basic frame structure used for transporting client signals.    - It includes:      - **Payload Area:** Carries the client data.      - **OTUk Overhead:** Provides management and monitoring functions.      - **OTUk FEC (Forward Error Correction):** Used for error detection and correction. 2. **ODUk (Optical Data Unit, level k):**    - The ODUk is a sub-layer wi...
Read more

OTN related alarms

In OTN (Optical Transport Network) technology, several alarms and indicators are used to monitor and troubleshoot network performance. Here are some common OTN-related alarms: ### **1. Loss of Signal (LOS)**    - Triggered when there is a complete loss of optical signal.    - Possible causes: Fiber cut, transmitter failure, or disconnected cable. ### **2. Loss of Frame (LOF)**    - Indicates that the OTN frame synchronization is lost.    - Possible causes: High bit errors, signal degradation, or equipment malfunction. ### **3. Loss of MultiFrame (LOM)**    - Occurs when the OTN multiframe alignment is lost.    - Possible causes: Synchronization issues or signal impairments. ### **4. Signal Degrade (SD)**    - Indicates degraded signal quality (BER exceeds threshold).    - Possible causes: Optical power issues, dispersion, or interference. ### **5. Signal Fail (SF)**    - Triggered when signal quali...
Read more