Polycom SIP 2.2.2 - Manual (Page 19)

Overview
2 - 3
Session Initiation Protocol Application Architecture
The software architecture of SIP application is made of 4 basic components:
• BootROM —loads first when the phone is powered on
• Application —software that makes the device a phone
• Configuration —configuration parameters stored in separate files
• Resource Files —optional, needed by some of the advanced features
BootROM
The bootROM is a small application that resides in the flash memory on the
phone. All phones come from the factory with a bootROM pre-loaded.
The bootROM performs the following tasks in order:
1. Performs a power on self test (POST).
2. (Optional) Allows you to enter the setup menu where various network on
provisioning options can be set.
The bootROM software controls the user interface when the setup menu is
accessed.
3. Requests IP settings and accesses the boot server to look for any updates
to the bootROM application.
If updates are found, they are downloaded and saves to flash memory,
eventually overwriting itself after verifying the integrity of the download.
4. If a new bootROM is downloaded, format the file system clearing out any
application software or configuration files that may have been present.
Configuration
Resource
Files
bootROM
Application