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Forum Replies

  1. Hello Brian

    MAC addresses when configured have the U/L bit which is the 7th bit of the 48 bit address. This bit, when set to 0 when this address is locally administered and 1 if the address is globally unique. An example is the virtual MAC address that is created by HSRP. This MAC address will always have 0 in the seventh bit, while a hardwired MAC address on a switch or a PC will have the 7th bit 1.

    Now because there is a mechanism of EUI-64 which is used to assign an IPv6 address that is derived from a MAC addresses, this L bit seems to have migrated into

    ... Continue reading in our forum

  2. Hi Rene,
    I have a silly question running over my head. I see that we have Global unicast address, somewhere i read that the range for global unicast is from 2000::/16 to 3fff::/16.
    My question:

    1. is this correct?
    2. why such a small range of global unicast addresses from a massive IPv6 address? Your introduction to IPv6 course mentioned that there is no real requirement of NAT in IPv6. With this small range we might require NAT in future (please correct me if i am wrong)
    3. can’t we assign other addresses like 7000::/16 as global unicast ?
      I know that IANA does the ad
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  3. Hi Nadav,

    The global IPv6 unicast address space must start with 001 (binary) so that’s correct yes:

    0010 (2000)
    0011 (3000)

    In other words, it has to start with 2000::/3. That covers everything in this range:


    That’s 42535295865117307932921825928971026432 addresses in total.

    For each person on the planet we get:

    42535295865117307932921825928971026432 / 7615097670 (world population) = 5.5856534e+27

    So, that’s a crazy number of IPv6 addresses only from the 2000::/3 range :smile:

    Here you can

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  4. Hello Nadav

    Anycast can indeed provide redundancy. With the growth of the Internet, many network services are using Anycast for high-availability requirements, such as DNS and content delivery networks. Anycast has grown in popularity for this purpose.

    ... Continue reading in our forum

  5. well received, thanks for these answers

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