Methods and apparatuses for data compression
A plurality, i.e. at least two, cells are combined into a macro cell. In a macro header of said macro cell a full numbering information of a first cell of said plurality of cells is stored. For further cells of said plurality of cells other than said first cell, a deviation information indicating a deviation of a numbering information of the respective further cell from said full numbering information of said first cell or one of said further cells is stored. In some embodiments, additionally the headers of the individual cells are incorporated in the macro header.
1 . A method for header compression, comprising:
assigning information to be transmitted to a plurality of cells,
assigning a numbering information to each cell of said plurality of cells, and
storing said numbering information in at least one header to be transmitted with said plurality of cells, wherein said storing step comprises:
storing the full numbering information of at least a first one of said plurality of cells in said at least one header, and
storing a deviation of the numbering information of at least a second one of said plurality of cells from said full numbering information in said at least one header.
2 . The method according to claim 1 , comprising:
combining said plurality of cells to a macro cell, wherein said at least one header comprises a macro header of said macro cell.
3 . The method according to claim 2 ,
wherein said macro header of said macro cell further comprises compressed headers of said cells.
4 . The method according to claim 1 ,
wherein said numbering information is a sequence index for bonding of a plurality of links for transmitting said cells.
5 . The method according to claim 1 ,
wherein said cells are ATM cells.
6 . The method according to claim 1 , wherein said assigning step comprises:
determining if a cell to which a numbering information is to be assigned is one of a control cell and an idle cell assigning a numbering information corresponding to a numbering information of one of a cell preceding said cell and a cell following said cell to said cell if said cell is one of a control cell and an idle cell.
7 . The method according to claim 6 ,
wherein said control cell is an autonomous status message.
8 . A method for header decompression, said method comprising:
providing a plurality of cells having at least one header,
retrieving a full numbering information of a first one of said plurality of cells from said at least one header, retrieving deviation information representing the deviation of a numbering information of at least a second one of said cells from said full numbering information from said at least one header, and
reconstructing said numbering information of said second one of said plurality of cells from said full numbering information and said deviation information.
9 . The method according to claim 8 ,
wherein said plurality of cells are combined to a macro cell, and wherein said at least one header is a macro header of said macro cell.
10 . The method according to claim 9 ,
wherein said macro header comprises compressed headers of said plurality of cells, said method further comprising:
decompressing said compressed headers.
11 . The method according to claim 8 ,
wherein said numbering information is a sequence index for bonding of a plurality of links over which said cells are received.
12 . The method according to claim 8 ,
wherein said cells are ATM cells.
13 . A method for data decompression, comprising:
receiving compressed data,
attempting to decompress said data using compression information, and
if said attempt fails, requesting updated compression information from a sender of said compressed data.
14 . The method according to claim 13 ,
wherein said compression information comprises a lookup table.
15 . The method according to claim 13 ,
wherein said compressed data is a compressed header of a cell.
16 . The method according to claim 15 ,
wherein said cell is an ATM cell.
17 . The method according to claim 15 ,
wherein said compressed header is stored in a macro header of a macro cell combining a plurality of cells.
18 . The method according to claim 13 ,
wherein said requesting step comprises sending a requesting cell to said sender.
19 . A method for transmitting data, comprising:
compressing data using compression information,
transmitting said compressed data, and
upon receiving a request from an entity receiving said data, sending said compression information.
20 . The method according to claim 19 ,
wherein said compression information comprises a lookup table.
21 . The method according to claim 19 ,
wherein said data to be compressed comprises a header of a cell.
22 . The method according to claim 21 ,
wherein said cell is an ATM cell.
23 . The method according to claim 21 ,
wherein said compressed data is stored in a macro header of a macro cell combining a plurality of said cells.
24 . The method according to claim 19 , further comprising:
periodically sending said compression information.
25 . An apparatus for header compression, comprising:
a cell builder to assign information to be transmitted to a plurality of cells, to assign a numbering information to each cell of said plurality of cells, and
to store said numbering information in a header to be transmitted with said plurality of cells, wherein said storing comprises: storing the four numbering information of at least a first one of said plurality of cells in said at least one header, and storing a deviation of the numbering information of at least a second one of said plurality of cells from said full numbering information in said at least one header.
26 . The apparatus according to claim 25 , wherein said plurality of cells are combined to a macro cell, wherein said at least one header is a macro header of said macro cell.
27 . The apparatus according to claim 26 ,
wherein said macro header of said macro cell further comprises compressed headers of said cells.
28 . The apparatus according to claim 25 ,
wherein said numbering information is a sequence index for bonding of a plurality of links for transmitting said cells.
29 . The apparatus according to claim 25 ,
wherein said cells are ATM cells.
30 . The apparatus according to claim 25 , further comprising:
a transmitter to transmit said cells.
31 . A apparatus for header decompression,
wherein said at least one header is associated with a plurality of cells,
said apparatus comprising:
a cell analyzer to retrieve a full numbering information of a first one of said plurality of cells from said at least one header, to retrieve deviation information representing the deviation of a numbering information of at least a second one of said cells from said full numbering information from said at least one header, and to reconstruct said numbering information of said second one of said plurality of cells from said full numbering information and said deviation information.
32 . The apparatus according to claim 31 ,
wherein said plurality of cells are combined to a macro cell, and wherein said at least one header is a macro header of said macro cell.
33 . The apparatus according to claim 31 ,
wherein said macro header comprises compressed headers of said plurality of cells.
34 . The apparatus according to claim 31 ,
wherein said numbering information is a sequence index for bonding of a plurality of links over which said cells are received.
35 . The apparatus according to claim 31 ,
wherein said cells are ATM cells.
36 . An apparatus for data compression, comprising:
a receiver,
a decompressor attempting to decompress compressed data received by said receiver using decompression information, and
a transmitter to request updated compression information from a remote transmitter of said compressed data if said attempt fails.
37 . The apparatus according to claim 36 ,
wherein said compression information comprises a lookup table.
38 . The apparatus according to claim 36 ,
wherein said compressed data is a compressed header of a cell.
39 . The apparatus according to claim 38 ,
wherein said cell is an ATM cell.
40 . The apparatus according to claim 38 ,
wherein said compressed header is stored in a macro header of a macro cell combining a plurality of cells.
41 . An apparatus for transmitting compressed data, comprising:
a data compressor to compress data using compression information,
a transmitter to send said compressed data, and
a receiver to receive requests from an entity receiving said data, wherein said transmitter transmits said compression information when said receiver receives a request requesting said compression information.
42 . The apparatus according to claim 41 ,
wherein said compression information comprises a lookup table.
43 . The apparatus according to claim 41 ,
wherein said data being compressed is a header of a cell.
44 . The apparatus according to claim 43 ,
wherein said cell is an ATM cell.
45 . The apparatus according to claim 43 ,
wherein said compression data is stored in a macro header of a macro cell combining a plurality of said cells.
46 . A macro header for a macro cell, said macro cell combining a plurality of cells, comprising:
full numbering information for at least a first one of said plurality of cells, and
deviation information representing a deviation of a numbering information of at least a second one of said plurality of cells from said full numbering information of said at least first one of said plurality of cells.
47 . The macro header according to claim 46 , further comprising:
header information for each cell of said plurality of cells.
48 . The macro header according to claim 47 ,
wherein said header information is compressed according to a lookup table.