Protocols Flashcards
What is IGMP and what is it used for?
Internet Group Messaging Protocol (IGMP) is a protocol that allows several devices to share one IP address so that they can receive the same data.
It is a network layer protocol used to set up multicasting on networks that use IPv4. Specifically, IGMP allows devices to join a multicasting group.
What is multicasting?
Multicasting is when a group of devices all receive the same messages or packets. Multicasting works by sharing an IP address between multi devices. Any network traffic directed at that IP address will reach all devices that share the IP address, instead of just one device. This is much like when a group of employees all receive company emails directed at a certain email alias.
What is PIM and what is it used for?
Protocol Independent Multicast (PIM) is a collection of multicast routing protocols, each optimized for a different environment. PIM sparse mode and PIM dense mode.
What are the two main PIM protocols and what do they do?
PIM sparse mode (PIM-SM): a “pull” model where multicast traffic is only forwarded when requested
PIM dense mode (PIM): a “push” model where multicast traffic is flooded everywhere and then pruned when it’s not needed
PIM sparse-dense mode: allows devices to operate in either sparse or dense mode (this is what we used as best practices)
