I've always been kind of conflicted with this issue. I mean, providers
blocking traffic at all.
On the one hand, I'm a corporate customer, and if I'm being DOSed or
infected, I would want to be able to call my ISP and have it blocked.
On the other hand, I truly feel that I pay my ISPs to pass traffic, not
block it.
I guess it only bugs me when something is blocked and I didn't even ask
for it to be blocked...and then other stupid things are seeping through,
but are not blocked even when I ask!
If ISPs really wanted to make the Internet better for Corporate America,
I guess they'd unplug most of Asia...not block a port here and there
(but that isn't exactly acceptable).
Anways, like I said, I'm conflicted...I change my mind every now and
then because both arguments make logical sense.
If ISPs really wanted to make the Internet better for Corporate America,
I guess they'd unplug most of Asia...not block a port here and there
(but that isn't exactly acceptable).
If I (working for an ISP in Norway) wanted to make the Internet better
for my customers, I'd unplug lots of U.S. sites - because that's where
most of the spam (and the products the spam advertises) comes from.
I may be off base here. Can't an ips look at the traffic; say on 443 and figure out whether the traffic is malicious or not? If so then let it filter it. I know IPS's aren't perfect, but, i would prefer this router be taken, if available and sensible including network outage or DDOS, than a hard block. A quick block to mitigate and then an IPS rule installed AFTER through investigation of the traffic could lessen the load and maybe eliminate the malicious traffic without having to use a hard block. I know most here prefer not to..i am not saying this is a let's block is all thread, just trying to throw out something i do not see being discussed.
I think the point of many on this list is, they are a transit provider, not a security provider. They should not need to filter your traffic, that should be up to the end user/edge network to decide for themselves.
Additionally, content filtering is great for those type of end-user folks, as this solution wouldn't be so difficult to scale for their traffic volumes. However, trying to content filter a transit provider is probably not a great idea.
I may be off base here. Can't an ips look at the traffic; say on 443 and figure out whether the traffic is malicious or not?
Well, your particular example is perhaps not the best one. 443 is SSL, and looking within the encrypted traffic is not something an IPS running on a separate box is going to be good at. Anything that's not encrypted, sure.
The IPS could notice an excessive connect rate (TCP) or packet rate (any protocol) and attempt to do something in terms of attack mitigation, even for encrypted sessions.
If so then let it filter it. I know IPS's aren't perfect, but, i would prefer this router be taken, if available and sensible including network outage or DDOS, than a hard block. A quick block to mitigate and then an IPS rule installed AFTER through investigation of the traffic could lessen the load and maybe eliminate the malicious traffic without having to use a hard block. I know most here prefer not to..i am not saying this is a let's block is all thread, just trying to throw out something i do not see being discussed.
One of the dangers is more and more stuff is being shoved over a limited set of ports. There are VPNs being built over SSL and HTTP to help bypass firewall rule restrictions. At some point we end up with another protocol demux layer, and a non-standard one at that if we push more and more restrictive filters out there. This in the long run is going to cause many problems.
Also note that the IPS would likely be at the customer end of a circuit, meaning a flood attack might still fill the pipe, and your ISP isn't going to be able to alleviate that.
One of the dangers is more and more stuff is being shoved over a limited set of ports. There are VPNs being built over SSL and HTTP to help bypass firewall rule restrictions. At some point we end up with another protocol demux layer, and a non-standard one at that if we push more and more restrictive filters out there. This in the long run is going to cause many problems.
Isn't SSL VPN exactly another protocol demux layer, though it might be a standard one?