Almost all physicians complete at least 4 years of undergraduate school, 4 years of medical school, and, depending on their specialty, 3 to 7 years in internship and residency programs. Most applicants to medical school have at least a bachelor's degree, and many have advanced degrees.
/bi:t/ (B) A component in the machine data hierarchy larger than a bit and usually smaller than a word; now nearly always eight bits and the smallest addressable unit of storage. A byte typically holds one character. A byte may be 9 bits on 36-bit computers.
Yes, you do need a maximum of 15 characters to store an IP address as a string. Alternatively you can save a lot of space by storing your IPs as 4-byte unsigned integers. Then use ip2long(), long2ip() string conversions in your application layer.