using "reserved" IPv6 space

Scott Morris swm at
Sun Jul 15 13:30:29 UTC 2012

On 7/15/12 5:38 AM, Grzegorz Janoszka wrote:
> On 2012-07-15 00:45, Tony Hain wrote:
>> There is no difference in the local filtering function, but *IF* all transit
>> providers put FC00::/7 in bogon space and filter it at every border, there
>> is a clear benefit when someone fat-fingers the config script and announces
>> what should be a locally filtered prefix (don't we routinely see unintended
>> announcements in the global BGP table).   I realize that is a big IF, but
> There was also in the past fec0::/10. For BGP updates you should be safe
> to filter out FC00::/6.

Unless I've missed something, RFC4193 lays out FC00::/7, not the /6.  So
while FE00::/7 may yet be unallocated, I don't think I'd set filters in
that fashion.

Reasonably, wouldn't it be more likely to permit BGP advertisements
within the 2000::/3 range as that's the "active" space currently?


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