IP addressing: CIDR

CIDR stands for Classless Interdomain Routing

  • Each IP address has a portion of arbitrary length which defines a subnet
  • The address format is a.b.c.d/x, where x is the number of bits in subnet portion of address
    Classless Interdomain Routing
  • A subnet is formed by device interfaces with same subnet part of IP address
    • Can physically reach each other without intervening router

Question

How many subnets can you find?

Figure shows a network topology with three routers, three subnetworks and three links. Routers are interconnected forming a triangle, and each router hosts a subnet.
Check answer
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