Pdh vs sdh describes difference between pdh and sdh

SONET for Past

As expected, the SONET scenarios have a low initial cost. When the traffic volume is low, a SONET architecture is much more economical compared to DWDM architecture. FS’s modeling indicates that when designing a SONET overlay network with OC-3, OC-12, OC-48 and Gigabit Ethernet demands so when the design requires under 4-10 OC-192 rings, a SONET network is a perfect choice.

DWDM for Now and Future

As the traffic volume grows, DWDM will eventually prevail and become the choice of the network technology. Timing of this crossover is responsive to such things as the span distances, pricing and interface density. The differences between demand types mostly are caused by the design efficiency of these two technologies’ interface cards in terms of density and price. FS’s study also shows span distances usually trigger the extra requirement for regenerators, optical amplifiers and DCMs in the routes. Long span distance has a tendency to favor a DWDM architecture because of the efficient utilization of fibers and optical bypass capabilities at intermediate nodes.

Additionally, higher fiber cost and situations in which fiber constraints are enforced will lead to more consideration for DWDM than SONET because DWDM saves a tremendous amount of fiber within the optical network. DWDM systems could be planned for a large number of channels, however, pay-as-you-grow strategy can be used and channels added based on demand in FS. The amplifier distance and overall power budget of the system needs to be calculated for the final quantity of channels right from the start.

Figure 2: SONET vs DWDM

Conclusion

Different alternatives and their economic impact in designing exactly the same network is definitely an interesting study. SONET point-to-point performs better still. These results might not apply in all situations. However, the implication is the fact that, in large network designs, the most optimized network may not necessarily be a single architecture. One part of the network may adopt rings while another part implements point-to-point. Usually, the core part of the network will justify a DWDM architecture.