How do you integrate SDH protection with other transport network layers and services?

1 SDH protection schemes

SDH protection schemes are designed to switch the traffic from a working channel to a backup channel in the event of a failure or degradation of the working channel. There are two main types of SDH protection schemes: linear and ring. Linear protection schemes are applied to point-to-point or point-to-multipoint connections, while ring protection schemes are applied to circular or meshed topologies. Linear protection schemes can be further classified into 1+1, 1:1, and 1:N, depending on the ratio of working and backup channels. Ring protection schemes can be further classified into MSP (Multiplex Section Protection), SNCP (Sub-Network Connection Protection), and MS-SPRing (Multiplex Section-Shared Protection Ring), depending on the level and granularity of protection.

2 SDH protection integration challenges

Integrating SDH protection with other transport network layers and services poses several challenges, such as compatibility, coordination, scalability, and cost. Compatibility issues may arise due to different protection schemes, protocols, and standards. Coordination problems might occur due to different protection switching triggers, criteria, and priorities. Additionally, different bandwidth and capacity requirements can affect the availability and utilization of the SDH protection channels. Lastly, different cost implications may impact the trade-off between the level of protection and the investment in the SDH network infrastructure.

3 SDH protection integration solutions

Integrating SDH protection with other transport network layers and services necessitates solutions such as adaptation, coordination, and optimization. The adaptation layer is the interface between the SDH layer and the upper layer service, performing functions such as mapping, framing, multiplexing, and demultiplexing the upper layer signals into the SDH containers. The coordination layer determines the optimal protection switching strategy for the SDH network and the upper layer service, considering factors such as the type and severity of the failure, the availability and quality of the backup channel, and more. The optimization layer maximizes performance and utilization of the SDH network and upper layer service by monitoring, analyzing, optimizing, and reconfiguring network parameters such as channel allocation and bandwidth allocation. This layer also adapts to changing network conditions to ensure optimal protection level and service quality.

4 SDH protection integration examples

Integrating SDH protection with other transport network layers and services can be seen in examples such as Ethernet over SDH, IP over SDH, and OTN over SDH. Ethernet is a widely used data communication protocol that operates at the data link layer and is mapped into SDH containers such as Virtual Concatenation (VCAT) or Link Capacity Adjustment Scheme (LCAS). Additionally, IP is a widely used data communication protocol that operates at the network layer and is mapped into SDH containers such as Packet over SONET/SDH (PoS) or Generic Framing Procedure (GFP). Lastly, OTN is a standard for transmitting data over optical fiber networks that operates at the optical layer and is mapped into SDH containers such as Optical Channel Data Unit (ODU) or Optical Channel Payload Unit (OPU). Protection schemes for each of these protocols can be used to provide protection for traffic within the SDH network.

5 SDH protection integration benefits

Integrating SDH protection with other transport network layers and services can bring several advantages, such as improved reliability and availability of data transmission, increased flexibility and adaptability for selecting the best suited protection scheme, and enhanced efficiency and utilization of network resources. All of these benefits enable the optimization of network parameters to meet the demands of the services.