Subj : A small questionary on ISPs
To   : Scott Street
From : Victor Sudakov
Date : Sat Oct 23 2021 19:51:52

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<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
 SS>     options=50b<RXCSUM,TXCSUM,VLAN_HWTAGGING,AV,CHANNEL_IO>
 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
 * Origin: Ulthar (2:5005/49)

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