Patent ID: 8718098
Filing Date: 2014-05-06
Classification: H04L,H04W

Abstract:
1. A method for compressing a time stamp, applied in a scenario of compressing a basic compression packet carrying an extended compression packet of type 3 in Robust Header Compression (ROHC), the method comprising: pre-setting a control bit (CTRLBIT) in a time stamp field of the basic compression packet to indicate an encoding mode; and setting a zero bit indication field in a time stamp field of the extended compression packet to indicate number information of bits of successive zeros; storing high bits of the time stamp to be transmitted in the time stamp field of the basic compression packet; counting and determining whether the number information is larger than a threshold of a particular encoding mode; if the number information is larger than the threshold, setting the CTRLBIT as a value indicating the particular encoding mode, storing the bits of successive zeros beginning from the highest bit of remaining bits of the time stamp to be transmitted after removing high bits in the zero bit indication field of the extended compression packet in a form of the number information, and storing remaining bits of the time stamp to be transmitted after removing the high bits and the bits of successive zeros in the time stamp field of the extended compression packet as low bits; if the number information is not larger than the threshold, setting the CTRLBIT as a value indicating a general encoding mode, and storing the remaining bits of the time stamp to be transmitted after removing the high bits in the time stamp field of the extended compression packet as low bits; wherein the CTRLBIT is in a form of 2 bits, to indicate the general encoding mode and the particular encoding mode, and to further indicate a grouping mode for the bits of successive zeros when indicating the particular encoding mode; the number information of the bits of successive zeros indicated by the zero bit indication field is group number information; after determining that the number information is larger than the threshold of the particular encoding mode, the method further comprises: determining the grouping mode for the particular encoding mode, and setting the CTRLBIT as a value representing the determined grouping mode; and the grouping mode is a mode, among grouping modes indicated by the CTRLBIT, of which each group has the same number of bits and the number of the groups is a minimum value for the bits of successive zeros, and storing the bits of successive zeros in a form of number information is storing a group number obtained by grouping the bits of successive zeros according to the grouping mode in the zero bit indication field of the extended compression packet.