backbones filtering unsanctioned sites

Todd Crane todd.crane at
Fri Feb 17 04:04:24 UTC 2017

I am not familiar with Cogent’s architecture but why couldn’t they just null route the IP address at their edge routers from within Spain? I am not a lawyer but from what I understand, since the Spanish government has zero say on what goes on outside of their borders, a court order that may or may not have been issued is not a legal defense for blocking access around the world. Furthermore, I think that this should be viewed as a malicious act and not as unfortunate consequence or a breach of contract. As far as letting them off the hook because they only offer a partial view of the route table, our contract never anything about partial views. Force majeure only applies to thing they have no control over. For that to apply, the court order, if that’s what it was, would have to apply to every jurisdiction in which they operate. I am also skeptical of this court order, seeing as Ars was unable to independently verify.

We used to have Cogent transit and it was the single worst experience I have been through in my professional life. Every time I had to deal with them, it felt more like what I would dealing with the mobs that control much of Russia. Therefore, I am very hesitant to assume even the slightest bit of good faith towards them.

> On Feb 16, 2017, at 5:06 PM, Baldur Norddahl <baldur.norddahl at> wrote:
> For transit maybe Cogent should have dropped the route, so they did not advertize a route to peers that included null routed parts.
> Den 16/02/2017 kl. 21.52 skrev Jean-Francois Mezei:
>> On 2017-02-16 14:59, Sadiq Saif wrote:
>>> From -
>> Many thanks.
>> pardon my ignorance here, but question:
>> For an outfit such as Cogent which acts not only as a transit provider,
>> but also edge provider to large end users, can it easily implement such
>> a court order to block only edge interfaces and not to its transit
>> infrastructure?
>> (aka: propagate null routes for only to interfaces that
>> lead to end users, but leave core/GBP aspects without the block.)
>> Or is BGP and any internal routing protocols so intermingled that it
>> becomes hard to manage such blocks ?
>> The difficulty for network to block traffic becomes an important
>> argument when trying to convince governments that blocking should not be
>> done. (ex: Québec government wanting to block access to gambling sites
>> except its own).

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