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PGP and S/MIME Protocol

Both PGP and S/MIME protocols are used for authentication and privacy of messages over internet. S/MIME protocol refers to Secure/Multipurpose Internet Mail Extensions which has been incorporated in the various main exchange software, incl. Outlook, Thunderbird & others And also incorporated in all major browsers (chrome, Mozilla, IE and others). S/MIME is based on IETF standards and defined in RFC 5751.   RFC 5751 defined S/MIME as "S/MIME (Secure/Multipurpose Internet Mail Extensions) provides a consistent way to send and receive secure MIME data. Based on the popular Internet MIME standard, S/MIME provides the following cryptographic security services for electronic messaging applications: authentication, message integrity and non-repudiation of origin (using digital signatures), and data confidentiality (using encryption). As a supplementary service, S/MIME provides for message compression." PGP known as Pretty Good Privacy, is a data encryption and decryp

Google Public DNS Servers Hijacked on 16th March 2014

Google Public DNS Servers i.e., (which are running in Anycast mode)  was hijacked on 16th of March 2014 for the Internet users of Venezuela and Brazil for nearly 22 mins. Google's Public DNS servers are used for "130 billion DNS queries on average (peaking at 150 billion) from more than 70 million unique IP addresses each day." This makes Google most popular Public DNS service in the Internet world. It is suspected that Hackers exploited a well-know vulnerability in Border Gateway Protocol. There is no-way in BGP to check if particular IP address segment belongs to a particular ISP. RPKI and BGPSEC are the solution of this flaw but these two protocols are still in initial phase and lot or works needs to be done on these protocols. In this particular case, attack kept users from using the internet but no malicious activity has been traced till yet. No redirection of DNS traffic to rogue servers has been traced. This lead to suspect that someone might

Public DNS Servers

Domain Name Service (or Server or System) is an internet service that translate easily memorized domain names into IP numbers and vice-versa. DNS Servers can be better understands as Yellow page directory to the Internet. Every ISP runs DNS services for their customers and users. A user can also runs DNS service for its own. There are many DNS servers which are open for all, commonly known as Public DNS Servers. IP addresses of main Public DNS Servers are :- Google Public DNS Servers 1. 2. 3.   2001:4860:4860::8888 4.   2001:4860:4860::8844 Level 3 Public DNS Servers 5. 6. 7. 8. 9. 10. OpenDNS Public DNS Servers 11. 12. 13.      2620:0:ccc::2 14.      2620:0:ccd::2 Norton Public DNS Servers 15. 16. Comodo Secure Public DNS Server 17. 18. Other Public DNS Server 19.