This attribute specifies the maximum number of V.42bis codewords
the IWF supports. A codeword is a binary number that represents a
string of characters in compressed form. V.42bis keeps a dictionary
of codewords for each compression direction. During Exchange
Identification (XID) negotiation of parameter P1 (number of
codewords), both sides (IWF and mobile or IWF and Public
Switched Telephone Network (PSTN)) agree on the total number of
codewords in the dictionaries. Changes to this attribute impact the
compression ratio for the encoder (component GsmV42BisOp
attribute compRatioEncoder). Changes also impact the amount of
memory used (more memory is used when increasing the attribute).
The gain in performance obtained from the selection of a larger
dictionary may be offset by the larger codeword size needed, and
for certain types of data, better performance may be obtained by
using a smaller dictionary.
The negotiated value can be viewed in the component
GsmIwfV42bisOp attribute maximumCodewords . Changes to this
attribute do not effect existing calls.