Nortel Networks 553-3001-211 manual Memory, NTTK25 daughterboard

Page 802 of 894 NTDK20 Small System Controller card

Memory

The majority of system and customer configured data is both controlled and stored on the NTDK20 SSC card’s Flash ROM. An active and backup copy of customer data is also kept on the Flash ROM.

In the event of data loss, the NTDK20 SSC card also retains a copy of customer files in an area called the Backup flash drive. The NTDK20 SSC card is equipped with 8MB of temporary memory space called DRAM. DRAM functions much like RAM on a computer system. It stores and processes temporary automated routines and user-programmed commands while the system is running. The DRAM on the SSC card stores operating system files, user files, overlay data, patch codes, and the active copy of the customer database.

The NTDK20 SSC card’s Flash daughterboard is the NTTK25. It performs most of the system software storage and data processing.

NTTK25 daughterboard

The NTTK25 is a 48 MB daughterboard comprised of Flash ROM and

Primary Flash drive. It is required in the Call Server and MG 1000S.

The Flash ROM holds 32 MB of ROM memory, comprising operating system data and overlay programs. Flash ROM is expandable using an expansion flash daughterboard.

The Primary Flash drive contains 16 MB of storage space. Most of the data storage is allocated to the Primary Flash drive – the main storage area of customer configured data.

Other system data such as the Secure Storage Area (SSA) also resides in the Flash drive. The SSA holds data that must survive power interruptions.

The Boot ROM is a 2 MB storage device located on the NTDK20 SSC card. The Boot ROM contains the boot code, system data, patch data, and the backup copy of the Primary Flash drive’s customer database.

553-3001-211 Standard 2.00 September 2004