If the user wishes to indicate alternative values of low layer compatibility parameters (e.g. alternative protocol suites or protocol parameters), the Low layer compatibility information element is repeated in the SETUP message. Up to four Low layer compatibility information elements may be included in a SETUP message. The first Low layer compatibility information element in the message is preceded by the Repeat indicator information element specifying "priority list for selection". The order of appearance of the Low layer compatibility information elements indicates the order of preference of end-to-end low layer parameters.
Alternatively, the network may discard the lower priority Low layer compatibility information element(s) depending on the signalling capability of the network.
If the network or called user does not support repeating of the Low layer compatibility information element, and therefore discards the Repeat indicator information element and the subsequent Low layer compatibility information elements, only the first Low layer compatibility information element is used in the negotiation.
The called user indicates a single choice from among the options offered in the SETUP message by including the Low layer compatibility information element in the CONNECT message. Absence of a Low layer compatibility information element in the CONNECT message indicates acceptance of the first Low layer compatibility information element in the SETUP message.
If bearer capability selection applies, then for each individual Low layer compatibility information element included in the SETUP message, the user shall ensure that there is no contradiction between the information contained in that Low layer compatibility information element and the information contained in at least one of the included Bearer capability information elements, either the fallback bearer capability, the preferred bearer capability, or both.