In networking, the acronym IS-IS stands for Intermediate System-to-Intermediate System.
Understanding IS-IS
IS-IS is a crucial component within the world of network routing protocols. According to the provided reference, it is defined as:
- An Interior Gateway Protocol (IGP). IGPs are used for routing information within a single autonomous system (a network or group of networks under a common administration).
- A routing protocol standardized by the Internet Engineering Task Force (IETF). This signifies its widely accepted and standardized nature.
- Commonly used in large Service Provider networks. This highlights its scalability and robustness for handling complex and extensive network infrastructures.
What does "Intermediate System" mean?
In the context of networking, an "Intermediate System" refers to a router. Therefore, Intermediate System-to-Intermediate System routing means routing information exchange and discovery between routers within the network.
Key Aspects of IS-IS
Here are some key takeaways about IS-IS, based on its definition and common usage:
- Purpose: To find the best path for data packets to travel between different networks within an autonomous system.
- Operation: Like other link-state routing protocols (such as OSPF), IS-IS routers exchange information about their local connections (links) and the state of those links. Each router then uses this information to build a complete map or topology of the network and calculate the shortest path to other destinations.
- Historical Context: IS-IS originated from the Open System Interconnection (OSI) protocol suite but was later adapted to route IP traffic, making it a popular choice alongside OSPF for IP routing.
In summary, when you encounter IS-IS in the context of networking, it refers to the Intermediate System-to-Intermediate System routing protocol, primarily used by large service providers to manage routing within their networks.
