BCP38 [Was: Re: TWC (AS11351) blocking all NTP?]

Livingood, Jason Jason_Livingood at cable.comcast.com
Wed Feb 5 00:31:58 UTC 2014

>>Can somebody explain to me why those who run eyeball networks are able
>> to block outbound packets when the customer hasn't paid their bill,
>> but can't seem to block packets that shouldn't be coming from that
>> cablemodem?
>i suspect the non-payment case is solved at a layer below three

In a DOCSIS network the source address verification (as Tony said) is
typically done on the CMTS IIRC. Turning a customer off for non-payment is
done in an accounts management / billing system.

While I am sure continuing to agree with each other that spoofing is bad,
we lack actionable data. ;-) As I said in another thread, I think someone
/ some group needs to invest to collect actual data and share the results

So any volunteers out there? I¹m sure there are lots of ways to underwrite
independent research on the subject (contact me off-list).


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