Which routing protocol is classful and does not support VLSM?

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Multiple Choice

Which routing protocol is classful and does not support VLSM?

Classful routing protocols determine subnet masks based on the address class and do not advertise the mask in their updates. Because of that, they can’t carry variable-length subnet masks (VLSM) and cannot differentiate subnets within the same classful network without manual summarization. RIPv1 is the classic example of this behavior: it uses the default classful mask for each address class and never includes a subnet mask in its updates, so VLSM isn’t supported. In contrast, RIPv2, OSPF, and EIGRP are classless and do carry subnet masks, enabling VLSM and more flexible subnetting.

Classful routing protocols determine subnet masks based on the address class and do not advertise the mask in their updates. Because of that, they can’t carry variable-length subnet masks (VLSM) and cannot differentiate subnets within the same classful network without manual summarization. RIPv1 is the classic example of this behavior: it uses the default classful mask for each address class and never includes a subnet mask in its updates, so VLSM isn’t supported. In contrast, RIPv2, OSPF, and EIGRP are classless and do carry subnet masks, enabling VLSM and more flexible subnetting.

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