CIDR and routing aggregation of TCP/IP

CIDR

(CIDR:, Classless, InterDomain, Routing) classless inter domain routing

  • Eliminate the traditional class A, class B, and class C address boundaries
  • NetID+SubID = Network Prefix (Prefix) can be of any length
  • The subnet address and subnet mask are fused to facilitate subnet partitioning
  • No class address format: a.b.c.d/x, where x is prefix length

for example

CIDR and routing aggregation of TCP/IP
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  • Subnet 201.2.3.64255.255.255.192 = 201.2.3.64/26

(CIDR:, Classless, InterDomain, and Routing)

  • Improving the allocation efficiency of IPv4 address space
  • Improve routing efficiency
  • Aggregate multiple subnets into a larger subnet
  • Supernetting structure (supernetting)

Route aggregation (route, aggregation)

That is, the aggregation of data that can be summed into the same subnet can reduce the burden of routing tables and speed up routing efficiency, as in the following example:

CIDR and routing aggregation of TCP/IP
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CIDR and routing aggregation of TCP/IP
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Hierarchical addressing makes routing information notifications more efficient:

CIDR and routing aggregation of TCP/IP
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Select more specific routing: longest prefix matching priority!

CIDR and routing aggregation of TCP/IP
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