please note that call preservation will only work with media flow around. if your provider does not support that or if it is routing wise impossible to achieve than you are flogging a dead horse.
from CUCM to CUBES it is fairly easy to make it redundant by using Route groups and OOB pings. calls into your organisation is different as your provider will need to support it, so hook up with them first and have a discussion re. your requirements.
thx
Please remember to rate useful posts, by clicking on the stars below.
