Optical Layer or Electrical Layer ASON?

Felipe  Platinum  (1)
3 years 8 months ago  View: 8223  Reply: 2

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.  

This post was last edited by Felipe at 2016-04-08 17:56.
H.H.M.Mohiuddin  Medium 
3 years 5 months ago

Clear distinction..!! thanks for share.
user_3373891  Jackeroo 
4 months 28 days ago
Nicely describe. Thanks.