Logical logs not backed up

We have an Informix Online 7.10 database with over 500GB of images. The database activity is mainly selects, with relatively few inserts. Our ltapedev is /dev/null - we do not back up the logical logs. The data is divided into 8GB dbspaces and we write to 1 dbspace at a time. When that dbspace is full we take onsite and offsite level 0 archives and move to the next dbspace. Our dbspace archive collection spans a year, as we refresh dbspace backups annually. Nightly we archive the rootdbs, the index dbspace and the active data dbspace. We are trying to understand the restoration implications of this scenario and to determine whether there is a practical alternative. Any suggestions/comments appreciated. Thanks, Barbara Grant bgrant@attcapital.com