Which versions of RIP are applicable for IPv4?

RIP (Routing Information Protocol) has two versions that are specifically designed for use with IPv4: RIPv1 and RIPv2. RIPv1 is the original version and primarily supports classful routing, meaning it does not send subnet mask information, which can lead to issues in networks with variable-length subnet masks (VLSM). RIPv2, on the other hand, introduces support for classless routing, allowing it to include subnet masks and provide more efficient routing in complex networks. This enhancement makes RIPv2 suitable for modern IP addressing schemes.

RIPng is designed for IPv6 and is not compatible with IPv4, which is why options mentioning RIPng are incorrect in this context. The other options that may include RIP or variations of it alongside RIPng or solely focus on one version do not recognize both RIPv1 and RIPv2’s relevance to IPv4, confirming that these are not the correct choices for this question.