REPLY: 1:266/420 616e4a4a   
   MSGID: 2:5005/49 617405a2   
   CHRS: CP866 2   
   TZUTC: 0700   
   TID: hpt/fbsd 1.9.0-cur 2019-12-05   
   Dear Scott,   
      
   19 Oct 21 00:32, you wrote to me:   
    VS>> 2. A /64 on the internal interface of ISP-owned CPE   
      
    SS> If appears that 2 is the closest.   
      
    SS> Xfinity / Comcast of Dover, Delaware (USA)   
      
    SS> I've got a dynamic IPv6 Address on my router WAN side reporting (via a   
    SS> FUGLY web interface):   
    SS>     WAN IP Address (IPv6): 2001:558:6027:19:c4e3:1bee:faf8:939d   
    SS>     WAN Default Gateway Address (IPv6): fe80::201:5cff:fe80:6846   
    SS>     Delegated prefix (IPv6): 2601:48:c500:9340::/64   
      
      
    SS> Interally::   
    SS> Mac worstation [ifconfig en0] [GbE]   
    SS> en0: flags=8863 mtu 1500   
    SS>     options=50b   
    SS>     ether 14:98:77:33:fb:b5   
    SS>     inet6 fe80::14ad:ef4c:c045:132f%en0 prefixlen 64 secured scopeid   
    SS> 0x6   
    SS>     inet6 2601:48:c500:9340::c0e3 prefixlen 60 dynamic   
      
      
   This is very interesting. Why "prefixlen 60" on the LAN?   
      
   Victor Sudakov, VAS4-RIPE, VAS47-RIPN   
   --- GoldED+/BSD 1.1.5-b20170303-b20170303   
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