REPLY: 1:266/420 61746324   
   MSGID: 2:5005/49 6174fdcc   
   CHRS: CP866 2   
   TZUTC: 0700   
   TID: hpt/fbsd 1.9.0-cur 2019-12-05   
   Dear Scott,   
      
   23 Oct 21 15:24, you wrote to me:   
      
    SS>>>     inet6 2601:48:c500:9340::c0e3 prefixlen 60 dynamic   
      
    VS>> This is very interesting. Why "prefixlen 60" on the LAN?   
      
    SS> Perhaps - an educated guess here - Comcast's provided gateway has,   
    SS> potentially, 4 internal LAN interfaces.  It could be configured with a   
    SS> 5GHz WiFi subnet, a 2.4GHz one, the GbE ports, and a 'Xfinity Home'   
    SS> port.   I haven't investigated what the "Home" port is used for, but   
    SS> that may explain the breaking down of the /64 to /60.  Again, just a   
    SS> theory.   
      
   Whatever Comcast's intentions, are you sure that a LAN with a prefixlen   
   different from /64 will work properly? Will a non-standard prefix not break   
   SLAAC and other things?   
      
   This is where my theoretical knowledge is lacking, but I've always been warned   
   against using anything different from /64 on a LAN segment.   
      
   Victor Sudakov, VAS4-RIPE, VAS47-RIPN   
   --- GoldED+/BSD 1.1.5-b20170303-b20170303   
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