User:Sajidur89/3 drawbacks of dns

DNS is the most rigorious protocol to resolve human-friendly text-based resource names (in other specifically addresses) to IP addresses and probably this is why DNS is being uesd world-wide.Nevertheless,like other sophisticated protocols it has some subtle drawbacks too. The first drawback that is worth mentioning is security. The ubiquity of BIND as DNS server software paves the way for hackers to hack DNS servers and use the DNS implemantation in the way they want. DNS attacks occur in two different ways. First one is based on the flaws of implementation of DNS protocol and the other is based on the bugs present in the DNS software running on the DNS server. While talking about DNS attack the most commonly discussed terms in the literature are -- 1.DNS cache poisoning 2. DNS ID hacking and 3.DNS spoofing. DNS cache poisoning refers to an attack which corrupts the DNS cache data. In this kind of situation it is obvious that the users (clients) are directed to wrong locations (in other words the URLs are maped to differnet IP addresses). DNS spoofing refers to the action of answering a DNS request that was intended for another server (a “real” DNS server). The main intention of all above mentioned types of DNS attacks is to midrect (making a client to somewhere where he was not willing to go at the first place) the client.

Another disdvantage associated with DNS is its supported character set. DNS only supports ASCII character set. It does not support the UNI-CODE character set. So resource names cannot be internationalized because of this limitation.