difference between electrical & optical ASON

Hi,
On an OTN network, the most obvious difference between optical-layer ASON and electrical-layer ASON is as follows:
Optical-layer ASON requires the ROADM system for hardware support, but electrical-layer ASON does not need to.

Optical-layer ASON: Focus only on the FIU and OTU boards. Based on optical-layer ROADM, optical-layer ASON applies only to small- and medium-scale scenarios.

Electrical-layer ASON: Focus on tributary and line boards and use electrical-layer cross-connect ODUk logical ports, which are applicable to large-scale long-haul scenarios.

Thank you!

Hello friend hope it can help:
Optical Layer or Electrical Layer ASON?

Felipe Sevillano, Transport & Data Planning Department, TELECOM PERSONAL PARAGUAY

In order to compare which kind of ASON (automatic switching optical network) feature brings more benefits when protection and re-routing is an issue in the network, here goes a brief explanation of both technologies.

The optical ASON (also called WSON – wavelength switched optical network) is based on lambda switching. This needs to be implemented at least by using directionless functionality; this can be achieved by ROADM board that has the availability to change the color of a wavelength. If colorless function is added, this gives more freedom to the network to re-route services over different paths without taking in account the wavelength occupation.

Electrical ASON is based on ODUk switching at electrical layer of an OTN cross-connect board. So OTN switches and ROADM boards need to be used.

Due to optical ASON is based on lambda switching, the protection and re-route is more flexible and save in transponder resources because the same transponder can change on direction and color. For electrical ASON this scenario is different because multiple lambda paths needs to be pre-set from the beginning and, for sure multiple transponders are needed.

Meanwhile optical ASON saves on transponder usage, electrical ASON, in the other hand, have the advantage of control over more granular traffic at ODU level, going as low as 1Gbps traffic rate. Also convergence time is much lower for electrical ASON than optical ASON; this is because the first already have pre-set all the restoration paths in the control plane meanwhile optical ASON needs to calculate the best path for restoration.

In summary, if restoration time is critical and the traffic granularity of services don´t fill a complete lambda container (OTUk), this solution is more optimized and cost efficient, but if SLA for a services are not critical and the traffic granularity occupies all the lambda, optical ASON is the best solution.

https://forum.huawei.com/carrier/en/thread-120775-1-1.html

Thanks!