IGP may refer to any of the following:
1. Short for interior gateway protocol (sometimes also called interior routing protocol), IGP is a type of routing protocol used within an AS (autonomous system). IGPs are responsible for routing information between gateways and help keep routing tables up-to-date. Essentially, interior gateway protocol exits for internal network routing to ensure efficient and reliable communication within an organization's network.
There are two types of IGPs:
- Distance-vector protocol - The less complex of the two, this type utilizes hop count as a metric to determine the best path to a destination. An example of a distance-vector protocol would be RIP (Routing Information Protocol).
- Link-state protocol - This protocol is a bit more involved. It uses a database of network links and calculates the shortest path to a destination based on various metrics. A good example of a link-state protocol is OSPF (Open Shortest Path First).
2. Short for integrated graphics processor, IGP is another name for a graphics unit that's built into a computer. Unlike a discrete GPU (graphics processing unit), an IGP isn't a stand-alone component. Instead, it is usually integrated into the CPU (central processing unit) or soldered to the motherboard as part of the northbridge chipset. See our onboard definition for further information and related links.