https://help.ubuntu.com/community/SSH/OpenSSH/Keys
http://unix.stackexchange.com/questions/26924/how-do-i-convert-a-ssh-keygen-public-key-into-a-format-that-openssl-pem-read-bio
Generate 4096 bit keys;
ssh-keygen -t rsa -b 4096
Convert to PEM format;
openssl rsa -in ms-test -pubout -outform pem > ms-test.pub-509