A method of processing information relating to a set of networks, the method comprising: receiving, from a server at a user terminal of a communication system, hash values for identifiers of respective networks which belong to the set of networks, said hash values being generated using a hash function; the user terminal determining an identifier of a particular network which is available for communicating with the user terminal by communicating with an access point associated with the particular network or by receiving the identifier on a broadcast channel of the particular network from the access point; generating, at the user terminal, a hash value for the identifier of the particular network using said hash function; and comparing, at the user terminal, the hash value of the identifier of the particular network generated at the user terminal with the hash values received at the user terminal from the server to thereby determine whether the particular network belongs to said set of networks, wherein one of the identifiers of the networks which belong to the set of networks is a partial identifier, and wherein if in said comparing step the hash value of the identifier of the particular network does not match with any of the hash values received at the user terminal from the server then the method comprises removing a character from the identifier of the particular network and then repeating the steps of (i) generating, at the user terminal, a hash value for the identifier of the particular network using said hash function and (ii) comparing the hash value of the identifier of the particular network generated at the user terminal with the hash values received at the user terminal from the server to thereby determine whether the particular network belongs to said set of networks. receiving, from a server at a user terminal of a communication system, hash values for identifiers of respective networks which belong to the set of networks, said hash values being generated using a hash function; the user terminal determining an identifier of a particular network which is available for communicating with the user terminal by communicating with an access point associated with the particular network or by receiving the identifier on a broadcast channel of the particular network from the access point; generating, at the user terminal, a hash value for the identifier of the particular network using said hash function; and comparing, at the user terminal, the hash value of the identifier of the particular network generated at the user terminal with the hash values received at the user terminal from the server to thereby determine whether the particular network belongs to said set of networks, wherein one of the identifiers of the networks which belong to the set of networks is a partial identifier, and wherein if in said comparing step the hash value of the identifier of the particular network does not match with any of the hash values received at the user terminal from the server then the method comprises removing a character from the identifier of the particular network and then repeating the steps of (i) generating, at the user terminal, a hash value for the identifier of the particular network using said hash function and (ii) comparing the hash value of the identifier of the particular network generated at the user terminal with the hash values received at the user terminal from the server to thereby determine whether the particular network belongs to said set of networks.