ZyXEL Communications Multi-service Access Platform MSAP2000 - Manual (Page 102)

6. System Design
MSAP2000 Technical Manual V3.0 6-5
E1 link goes down, total traffic for all the subscribers’ module (FXS) will
be divided evenly among the rest of the E1 links that are available.
For digital or IP based service line, protection is also done at the uplink
or network side. In DDN network, the N+1 protection is done at the
router, FOM, or SDH where at least one tributary module is used as
protection for QE1M/GSH/N64M/LULT. Same thing in IP network
where multiple edge routers forms a protection group for the uplink of
all the AAM/ESM in case of link down or server failure.
Database and
Backup
MSAP2000’s MPM is equipped with a Flash Memory device; a portion
of the Flash Memory is reserved to function as local non-volatile
memory, for backup of information such as system configuration,
channel assignment, V5 related setting, alarm data, terminal data, and
user account data that can be restored or dumped and printed after
backup procedure is complete.