Classless Inter-Domain Routing (CIDR) Tools

Everything about this Classless Inter-Domain Routing address block

Base information

Address Block 100::/64
First address 100::
Last address 100::ffff:ffff:ffff:ffff
Hosts in range 18 446 744 073 709 551 616
Mask bits 64

IANA Special-Purpose Registry

This CIDR is in a special-purpose block reserved by IANA for special purposes.

Address Block 100::/64
Purpose Discard-Only Address Block
Allocation Date June 2012
Termination Date N/A
Source true
Destination true
Forwardable true
Globally Reachable false
Reserved by protocol false
Defined in RFC [RFC6666]


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CIDR information and calculator

Analyze a CIDR

Example: or 2001:db8::/32