Alcatel 1600 Series SDH Equipment Operation and Maintenance Guide

2.4 Network management access

Connect the configuration management interface (such as DCC, Ethernet) to the network management system (such as Alcatel 1350 NM). Set IP address, routing, and SNMP parameters to ensure that the network administrator can monitor all network elements.

Protection mechanism configuration and verification

The Alcatel 1600 series supports multiple network protections and device level redundancy, making it the core of ensuring 99.999% availability.

3.1 Line Protection (MSP 1+1/1:1)

Reuse Segment Protection (MSP): At the STM-1/4/16/64 level, configure 1+1 or 1:1 protection groups. In the 1+1 mode, both the working channel and the protection channel are sent simultaneously, and the receiving end selects the best option with a switching time of less than 50 ms. In the 1:1 mode, the protection channel can carry low priority additional services, but it needs to be preempted before switching.

Configuration steps: Add the optical ports in both directions to the same protection group through network management, and set the recovery method (non recovery or recovery, default recovery time is 5-12 minutes).

3.2 Subnet Connection Protection (SNCP)

Used for branch level protection, it can implement dual transmission and selective reception for channels such as 2M, 34M, 140M, or STM-1. In a ring network, SNCP can provide greater flexibility than MSP, allowing for business protection between nodes on any ring.

Configuration note: It is necessary to define protection subnets in the network management system, select working paths and protection paths for each channel, and set the waiting time for recovery.

3.3 Equipment redundancy

1660 SM and 1664 SM support main control crossover board (SCC/SCU) redundancy and power module 1+1 backup. Hot swappable design ensures that replacing faulty cards does not affect business operations.

Regularly perform switch testing (manual forced switch) to verify the effectiveness of redundancy, and it is recommended to conduct it once every quarter.

3.4 1686 WM wavelength protection

Configurable optical line protection (OLP) or customer side 1+1 protection. In OLP mode, both the primary and backup optical fibers transmit optical signals simultaneously, and the receiving end selects based on the optical power. Switching time<50 ms.

Business configuration and cross connection planning

4.1 High/Low Order Cross Capacity

The 1650 SMC has flexible high-order and low order cross matrices, supporting cross connections between any VC-4, VC-3, or VC-12. Before configuration, a time slot allocation table should be drawn to avoid conflicts.

1660 SM provides a large capacity 10G crossover and can simultaneously process multiple STM-64/16/4/1 signals, supporting efficient scheduling in mesh or ring topologies.

4.2 Hybrid configuration of branch units

1664 SM supports mixed installation of 140M, STM-1 electrical/optical, and STM-4 optical branch cards in the same chassis. For example, 2 STM-4 cards and 4 STM-1 cards can be configured simultaneously. Attention should be paid to the bus capacity limit (total bandwidth not exceeding 2.5G).

4.3 Data Business Bearer (1650 SMC/1660 SM)

The ISA module can map Ethernet frames to SDH virtual containers (such as GFP encapsulation) and dynamically adjust bandwidth using VCAT (Virtual Cascading) and LCAS (Link Capacity Adjustment). When configuring, it is necessary to ensure that the remote device supports the same protocol.

RPR (Resilient Packet Ring) function is suitable for data ring networks, providing self-healing capability within 50 ms and suitable for metropolitan data aggregation.

Daily operation and maintenance monitoring and performance analysis

5.1 Alarm Grading and Handling

SDH alarms are classified into Critical, Major, Minor, and Warning based on their severity. Common important alarms:

LOS (loss of signal): No light received, fiber optic connections and optical modules should be checked immediately.

LOF (frame loss): Unable to frame, possibly due to errors or clock synchronization.

MS-AIS (multiplex segment alarm indication): Upstream fault causes full "1" signal, upstream source needs to be located.

B1/B2/B3 bit error: indicates that there is a bit error in the line or channel, and it is necessary to check the trend of bit error rate to determine whether it is sustained degradation.

Handling principle: prioritize handling physical layer alarms such as LOS/LOF, and then handle high-order/low order channel alarms. Utilize the network management alarm association function to quickly locate the root cause.

5.2 Performance Monitoring (PM) Data

Each model supports 15 minute and 24-hour performance counters, including BIP error rate, ES (error seconds), SES (severe error seconds), and UAS (unavailable seconds).

Set a performance threshold (such as ES>10/15min), trigger an alarm when the threshold is exceeded, and provide early warning of line or optical module degradation.

5.3 Optical power monitoring

Real time monitoring of received and emitted light power through network management. If the received power deviates from the reference value by more than ± 3 dB, it is necessary to investigate connector contamination or fiber optic cable attenuation changes.