The RSeq header is used in provisional responses in order to transmit them reliably. It contains a single numeric value from 1 to 2**32-1. The value of the RSeq in each subsequent reliable provisional response for the same request MUST be greater by exactly one. RSeq numbers MUST NOT wrap around. Because the initial one is chosen to be less than 2**31 - 1, but the maximum is 2**32 - 1, there can be up to 2**31 reliable provisional responses per request, which is more than sufficient. As the RSeq numbering space is within a single transaction. This means that provisional responses for different requests MAY use the same values for the RSeq number.
A server must ignore Headers that it does not understand. A proxy must not remove or modify Headers that it does not understand.
sequenceNumber- the new Sequence number of this RSeqHeader
javax.sip.InvalidArgumentExceptionif supplied value is less than zero.