An information processing apparatus includes: a memory configured to store a first group of character strings each of which corresponds to a header name defined in accordance with a communication protocol for communication, a second group of character strings each of which corresponds to a character string that is obtained by converting the character strings of the first group into lower case letters or upper case letters, and a third group of character strings each of which is not identical to any of the character strings of the first group, the character strings of the third group being extracted from a signal received; an extracting unit configured to extract a header value from another signal received from the other communication apparatus when a header name included in the other signal is identical to any character string of the first group, or the third group, or the second group.