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1

Your benchmark is possibly incomplete. I have a server which features a CPU reported as: "Intel(R) Xeon(R) CPU E3-1220 V2 @ 3.10GHz". It has four cores. On that machine, OpenSSL 1.0.1f reports (with openssl speed ecdhp224) that it can perform 9096 ECDH instances per second, using the NIST P-224 curve (a fine curve, of security rated at "112 bits", comparable ...


2

It will take a long time doing useless computation. One could conceivably use a designated-verifier non-interactive computationally zero-knowledge argument that the rest of the message is well-formed. More usefully, use proofs of work and PKE with fast decryption.


9

Actually, sending a lot of requests (and wildly clicking is one of the way of doing that) is what the DoS is about. DoS is not about sending some specially prepared data that will kill your site (like exploits, ping of deaths etc.). It's about sending a lot of requests which are cheap to send but takes a long to process. If someone writes the program ...


23

The question is a bit vague, the short answer is Yes clicking on links could DoS your site. A for a more in-depth answer you would need to look at what those links are doing. For example if every time you clicked a link it ran some monstrous database query that used all your CPU power or Disk IO, or if the links played a video that would quickly saturate ...


0

Your code is good for monitoring users activity on the server but to be honest, It can't help preventing DDOS attacks since the aim of DDOS attacks is to send tons of requests to the server to make it too busy to respond to its intended users. your code seems to be doing lots of checking to determine if the number of requests has reached beyond your ...


1

It shouldn't matter. The 802.11 de-authentication attack is not attacking the computer so the Operating System of the client should not matter. It is attacking the network itself by telling the router that the clients are done the connection and are disconnecting. There are defences for de-authentication attacks but it is not based on the OS. It is ...


1

According to Wikipedia TCP and UDP flood. The list of attacks is too long to name all of them. I think it will be good exercises for you to do it alone. It's easy for example TCP flood will operate on layer 4 because UDP is operating on this layer(Transport layer).


2

You really can't. The issue is that the cookies are client-side and there are only two methods to fix the problem: ignore/accept the cookies or delete them. The former is probably easier than the latter, but I would not recommend it. There's a reason to keep cookies small -- they're not the full meal. (Why on earth would a server want to accept a ...


3

Most browsers have a limit on how many cookies they'll store for a single TLD. So, if the server is configured to allow a sufficiently large request to include all these cookies, the requests won't be rejected anymore. Apache has options like LimitRequestFields, LimitRequestFieldSize, etc. Setting these sufficiently high should allow the request to be ...


1

There are many cheap stress-testing services that offer a variety of attack vectors to attack with. Once you purchase a membership, you simply login to their website and input your site's URL/IP address and chose an attack method (UDP, SYN, HTTP, ect) Note that these services are usually illegally ran by teenagers trying to make a couple bucks. ...


0

(This may be a dupe; I have a vague memory of a similar question, but I can't find it now, so either my memory or my search-fu is defective, or it's been deleted.) Salt only works if you can tie the protected value to a public value (i.e. salt for hashing a password is stored with the corresponding userid). The only obvious match to an IPaddress is the ...


3

Take your website down, fix the security problem (that folder didn't come there by accident it was most likely put there through another vulnerability). Check your code for vulnerabilities, anonymous write on your ftp server, places in your code where there is a risk for command injection, SQL injection, etc... Next install a spamfilter and automatically ...


1

You could do a policy based QoS, this allows you to perform rate limiting on particular IP addresses based on a particular policy. This way, you can allow IP addresses to visit your side, but when they perform a particular action (accessing a certain port, accessing a particular URL...), you'll only allow a limited number of sessions. It will limit the ...


0

There are lots of solutions which vary in their sophistication and effort / price... you can refer to this article for some simple techniques: http://www.cisco.com/c/en/us/support/docs/security-vpn/kerberos/13634-newsflash.html There are of course paid of the shelf solutions including cloud based solutions so you dont have to do much on your side such as ...


0

No matter if you use rate limiting or not. If you're running a public server, which accepts incoming connections, it is always and anywhere vulnerable for a DDoS. Rate limiting can be useful to not congest the system, it could be a possible countermeasure against DoS but does not, by far, protect fully against a DoS attack.



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