Re: [Full-disclosure] is my ISP lying or stupid?



On 2012-03-18 16:09, James Condron wrote:

The routers of an ISP are sorta DHCP in the sense that the IPs are
dynamic- DHCP really works as one network whereas an ISP switch will
have a series of /30 vlans for obvious reasons. Getting an IP and
connection is more complex than that but already we're down to a
series of routers.

No, they'd use private VLANs with the default router in a promiscuous
sub-VLAN. That way they won't have to waste 4 IPs for every customer.
Customers with multiple IPs can be put in community sub-VLANs, if they
pay for it.
Networking works very differently within Service Provider networks. A
lot of it is technology that makes itself look like other technologies
you might be familiar with, but what is happening behind the scenes is
actually completely different.

Just thought you might like to know.

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