Pointer Justification Count, 12-4 | Cisco Systems ONS 15600 guide

Chapter 12 Performance Monitoring

12.3 Pointer Justification Count

Pointers are used to compensate for frequency and phase variations. Pointer justification counts indicate timing differences on SONET networks. When a network is not synchronized, frequency and phase variations occur on the transported signal. Excessive frequency and phase variations can cause terminating equipment to slip. These variations also cause slips at the SDH and plesiosynchronous digital hierarchy (PDH) boundaries.

Slips cause different effects in service. Voice service has intermittent audible clicks. Compressed voice technology has short transmission errors or dropped calls. Fax machines lose scanned lines or experience dropped calls. Digital video transmission has distorted pictures or frozen frames. Encryption service loses the encryption key, which causes data to be transmitted again.

Pointers align the phase variations in STS and Virtual Tributary (VT) payloads. The STS payload pointer is located in the H1 and H2 bytes of the line overhead. Clocking differences are measured by the offset in bytes from the pointer to the first byte of the STS synchronous payload envelope (SPE) called the J1 byte. A small number of pointer justification counts per day is not cause for concern. If the pointer justification count continues to rise or becomes large, action must be taken to correct the problem.

Figure 12-3shows pointer justification count parameters on the performance monitoring window. You can enable positive pointer justification count (PPJC) and negative pointer justification count (NPJC) performance monitoring parameters for LTE cards.

Figure 12-3 Viewing Pointer Justification Count Parameters

Pointer Justification Counts

Performance tab Card view

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Cisco ONS 15600 Reference Manual, R7.2

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ONS 15600 specifications

Cisco Systems ONS 15600 is a highly versatile optical networking platform designed to meet the demands of modern telecommunications and data services. This multiservice edge platform supports various transmission mediums and offers a wide array of features that enable efficient data transport. Ideal for service providers and large enterprises, the ONS 15600 is engineered to provide scalable and reliable optical transport solutions.

One of the notable features of the ONS 15600 is its capability to support multiple protocols, including SONET/SDH, Ethernet, OTN, and legacy TDM services. This flexibility allows users to tailor their networks according to specific service requirements while ensuring interoperability with existing infrastructure. The platform is designed to facilitate seamless service migration, accommodating both legacy and next-generation services.

The modular architecture of the ONS 15600 enhances its scalability. It allows for easy expansion by incorporating additional line cards or interface modules without requiring significant downtime. This modularity ensures that service providers can evolve their networks over time, responding to increasing bandwidth demands and new service offerings with ease.

Incorporating advanced technologies, the ONS 15600 employs Dense Wavelength Division Multiplexing (DWDM), significantly increasing the capacity of fiber networks by allowing multiple signals to be transmitted simultaneously over a single optical fiber. This capability helps to optimize fiber utilization and reduce operational costs. In addition, the platform supports Optical Transport Network (OTN) for improved error detection and correction, contributing to higher reliability and performance.

Another key characteristic of the ONS 15600 is its robust management capabilities. The platform can be managed through Cisco's Optical Networking Manager (ONM), providing a centralized interface for network configuration, monitoring, and troubleshooting. This enhances operational efficiency and minimizes downtime, allowing service providers to focus on delivering quality services to their customers.

The ONS 15600 also prioritizes security, offering various features like encryption and access control to safeguard sensitive data during transmission. With its combination of scalability, flexibility, and security, the Cisco ONS 15600 stands out as a reliable choice for organizations looking to enhance their optical networking capabilities while meeting the evolving demands of the digital landscape. Its commitment to quality and performance makes it a cornerstone of modern optical networks.

Cisco Systems ONS 15600 manual Pointer Justification Count, 12-4

Models: ONS 15600