Header elimination for real time internet applications

1. A method of compressing a header, comprising:

compressing a real-time transport protocol, RTP, header portion of packets by removing a time stamp in the header portion of the packets;

transmitting the packets at relative time offsets based on the removed time stamps;

storing the compressed packet in a medium access control—high speed, MAC-hs, buffer;

monitoring a time the compressed packet resides in the MAC-hs buffer;

inserting a time stamp into a MAC-hs header portion of the packet, the time stamp indicating the time the compressed packet resided in the MAC-hs buffer; and wherein

the transmitting step transmits the packets output from the MAC-hs buffer.

2. The method of claim 1 , wherein the transmitting step transmits the packets at same relative time offsets as indicated by the removed time stamps.

3. The method of claim 2 , wherein the transmitting step transmits the packets over a channel with a transmission time interval having a fixed timing relationship with respect to a period of RTP packet generation.

4. The method of claim 3 , wherein the transmission time interval matches the period of RTP packet generation.

5. The method of claim 1 , wherein the transmitting step transmits the packets over a channel with a transmission time interval having a fixed timing relationship with respect to a period of RTP packet generation.

6. The method of claim 5 , wherein the transmission time interval matches the period of RTP packet generation.

7. The method of claim 1 , further comprising:

outputting the packets from the buffer in sequence based on RTP sequence numbers in the RTP header portion; and wherein

the compressing step compresses the RTP header portion of the output packets.

8. The method of claim 1 , wherein the compressing step further eliminates a RTP sequence number from the RTP header portion.

9. The method of claim 1 , further comprising:

compressing a user data protocol, UDP, header portion of the packet by stripping off the UDP checksum.

10. The method of claim 1 , further comprising:

converting a user data protocol, UDP, portion of the packet to UDP-Lite; and

compressing the packet according to robust header compression, RoHC.

11. A method of decompressing a header, comprising:

decompressing a header portion of a real-time transport protocol, RTP, packet by inserting a extension bit and a marker bit established based on a known fixed number of vocoder packets in each RTP packet.

12. A method of compressing a header, comprising:

compressing a real-time transport protocol, RTP, header portion of packets by removing a time stamp in the header portion of the packets;

transmitting the packets at relative time offsets based on the removed time stamps;

storing the packet in buffer;

outputting the packets from the buffer in sequence based on RTP sequence numbers in the RTP header portion;

detecting a missing packet in the buffer based on the RTP sequence numbers of the stored packets; and

responding to the missing packet by performing one of:

(1) creating the missing packet by copying a packet having a RTP sequence number previous to a RTP sequence number of the missing packet and changing the RTP sequence number of the copied packet to that of the missing packet, (2) creating the missing packet by creating a packet with no payload and a RTP sequence number equal to a RTP sequence number of the missing packet, and (3) outputting a next packet in sequence, following the missing packet, after a set time from detecting the missing packet,

wherein the compressing step compresses the RTP header portion of the output packets.

13. A method of decompressing a header, comprising:

monitoring arrival times of packets at a receiver;

determining a real-time transport protocol (RTP) time stamp of a currently received packet based on the arrival time of the currently received packet;

decompressing a RTP header portion of the currently received packet by inserting the determined RTP time stamp into the RTP header portion; and

performing one of: (1) selectively buffering a packet after successful reception for a period of time based on a maximum number of permitted retransmissions for transmitting packets over a communication channel and (2) storing received packets in a buffer, outputting the stored, received packets from the buffer in sequence based on radio link control, RLC, unacknowledged mode, UM, sequence numbers in the packets, wherein the decompressing step decompresses the RTP header portions of the output packets.

14. A method of decompressing a header, comprising:

monitoring arrival times of packets at a receiver;

determining a real-time transport protocol (RTP) time stamp of a currently received packet based on the arrival time of the currently received packet; and

decompressing a RTP header portion of the currently received packet by inserting the determined RTP time stamp into the RTP header portion,

wherein the determining step determines the RTP time stamp of the currently received packet based on the arrival time of the currently received packet and a time stamp in a medium access control—high speed, MAC-hs, header portion of the currently received packet.

15. The method of claim 14 , wherein the determining step determines the RTP time stamp of the currently received packet based on the arrival time of the currently received packet, the time stamp in the MAC-hs header portion of the currently received packet, and a deduced over-the-air trip time of the currently received packet.

16. The method of claim 14 , further comprising:

detecting gaps in a stream of the packets based on a discarded packets indicator in the MAC-hs header portion.