Device functionalities negotiation, fallback, backward-compatibility, and reduced-capabilities simulation

A system comprising:

• a main device and an auxiliary device arranged to co-operate with each other, the main device being arranged to handle one or more functionalities, the auxiliary device being arranged to effect one or more functionalities;
• wherein the auxiliary device performs a first enumeration of its functionalities and a second enumeration of its functionalities to the main device;
• wherein the main device comprises an enumerating means for enumerating to the auxiliary device the functionalities of the auxiliary device for which the main device is arranged to handle after the first enumeration and prior to the second enumeration;
• and
• wherein the second enumeration hides those of its functionalities for which the main device is not arranged to handle.

An auxiliary device comprising:

• a computer readable storage medium, comprising instructions, that when executed cause:
• a plurality of functionalities to cooperate with a main device, wherein the main device comprises a computer readable storage medium, comprising instructions, that when executed cause:
• arranging the main device to handle one or more functionalities,
• the auxiliary device to effect at least one of the plurality of functionalities,
• the auxiliary device to perform a first enumeration of at least one of the plurality of functionalities and a second enumeration of at least one of the plurality of functionalities to the main device;
• wherein the second enumeration is performed after the first enumeration and after the main device has enumerated to said auxiliary device the functionalities of the auxiliary device for which the main device is arranged to handle or for which the main device is not arranged to handle;
• and
• wherein the second enumeration hides of its functionalities for which the main device is not arranged to handle.

A computer readable storage medium, comprising instructions, that when executed cause the performance a method, the method comprising:

• a main device and an auxiliary device arranged to co-operate with each other, the main device being arranged to handle one or more functionalities, the auxiliary device being arranged to effect one or more functionalities;
• wherein the method comprises an adaptation step, in which the auxiliary device performs a first enumeration of its functionalities;
• wherein the method further comprises an enumeration step in which the auxiliary device performs a second enumeration of its functionalities to the main device;
• wherein the main device enumerates to the auxiliary device the functionalities of the auxiliary device for which the main device is arranged to handle after the first enumeration and prior to the second enumeration;
• and
• wherein the second enumeration hides those of its functionalities for which the main device is not arranged to handle.

A method of configuring a system comprising:

• a main device and an auxiliary device arranged to co-operate with each other, the main device being arranged to handle one or more functionalities, the auxiliary device being arranged to effect one or more functionalities;
• wherein the method comprises an adaptation step, in which the auxiliary device performs a first enumeration of its functionalities to the main device;
• wherein the method further comprises an enumeration step in which the auxiliary device performs a second enumeration of its functionalities to the main device;
• and
• wherein the main device enumerates to the auxiliary device the functionalities of the auxiliary device for which the main device is not arranged to handle after the first enumeration and prior to the second enumeration;
• and
• wherein the second enumeration hides from the main device at least those of its functionalities for which the main device is not arranged to handle.

A system comprising:

• a main device and an auxiliary device arranged to co-operate with each other, the main device being arranged to handle one or more functionalities, the auxiliary device being arranged to effect one or more functionalities;
• wherein the auxiliary device performs a first enumeration of its functionalities and a second enumeration of its functionalities to the main device;
• wherein the main device comprises an enumerating means for enumerating to the auxiliary device the functionalities of the auxiliary device for which the main device is not arranged to handle after the first enumeration and prior to the second enumeration;
• and
• wherein the second enumeration hides those of its functionalities for which the main device is not arranged to handle.

A computer readable storage medium, comprising instructions, that when executed cause the performance of a method, the method comprising:

• a main device and an auxiliary device arranged to co-operate with each other, the main device being arranged to handle one or more functionalities, the auxiliary device being arranged to effect one or more functionalities;
• wherein the method comprises an adaptation step, in which the auxiliary device performs a first enumeration of its functionalities;
• wherein the method further comprises an enumeration step in which the auxiliary device performs a second enumeration of its functionalities to the main device;
• and
• wherein the main device enumerates to the auxiliary device the functionalities of the auxiliary device for which the main device is not arranged to handle after the first enumeration and prior to the second enumeration and;
• wherein the second numeration hides those of its functionalities for which the main device is not arranged to handle.