The router operating system is a piece of software responsible for managing the router resources by controlling and allocating memory, prioritizing system requests and processes, controlling I/O devices and managing file systems.
The most two famous router operating systems are Cisco IOS and Juniper JUNOS.
Cisco IOS is a monolithic OS which means it runs as a single operation with all processes sharing the same memory space. This means a bug in one process can impact or corrupt other processes also means that adding new features to the OS requires upgrading the full IOS image itself.
JUNOS is a modular operating system with a FreeBSD based kernel. All processes run in separate modules and protected memory spaces. This modularity enhances uptime of the router because bugs will not affect the entire operating system and new features can be added without disabling the operating system or requiring a full upgrade.
Cisco is actually overcoming these limitations by introducing new modular versions of the IOS like IOS XR and IOS XE that are based on dedicated kernels.
Both operating systems are almost identical in the normal processes and features that are based on technology standards.
thats all for today.Please share your comments,ideas or questions.