Method and system for encapsulating time division multiplex data into individual packets of a packet based network
View Patent ↗A method of encapsulating TDM data into individual data packets for transmission across a packet network includes delineating the TDM data into one or more signaling multiframes, wherein each signaling multiframe includes one period of a periodic signaling pattern. The method also includes appending a header that is associated with the individual data packets to each of the signaling multiframes of TDM data. Further, a method of selecting the number of multiframes of TDM data in the data packet includes calculating the efficiency of the data packet as a function of the number of multiframes, and selecting the number of multiframes so that the efficiency of the data packet increases exponentially as a number of time-slots in the TDM data increases.
1. A method of selecting a value of a parameter k, wherein the parameter k represents a number of multiframes of TDM data in a data packet for transmission across a packet network, and the packet includes packet payload data and packet overhead data, comprising:
calculating one or more values of the parameter k as a function of one or more input parameters, each value of k corresponding to n, a number of time-slots in the TDM data, such that the efficiency of the data packet increases exponentially as the number of time-slots in the TDM data increases; and,
selecting a value of the parameter k corresponding to the input parameters associated with the payload data and the overhead data.
2. A method according to claim 1 , further including calculating the parameter k such that
k
=
Ceiling
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the input parameters including OH, M, N mx , τ, n, EF 1 , wherein:
OH represents an amount of packet overhead data;
M represents an amount of frames in a signaling multiframe of the TDM data;
N mx represents a maximum amount of times slots per frame associated with the TDM data;
τ represents a time constant;
n represents an amount of time-slots associated with the TDM data;
EF 1 represents a minimum allowed efficiency of the data packet;
and Ceiling[ ] represents a function for limiting the parameter k to an integer value.
3. A method according to claim 1 , further including delineating the TDM data such that a first byte in the one or more signaling multiframes is directly adjacent to the header.
4. A method according to claim 1 , further including appending an RTP header to each of the signaling multiframes.
5. A method according to claim 4 , further including appending a modified RTP header to each of the signaling multiframes.
6. A method according to claim 1 , further including extracting the TDM data from one or more time-slots from a TDM data stream.
7. A system for compiling one or more data packets for transmission across a packet network, each packet including packet payload data and packet overhead data, wherein a parameter k describes the number of multiframes of TDM data in each data packet, and a parameter n describes a number of time-slots in the TDM data, comprising: a processor (i) for calculating one or more values of the parameter k as a function of one or more input parameters, such that each value of k corresponds to a value of n, and the efficiency of the data packet increases exponentially as n increases, and (ii) for selecting a particular value of the parameter k corresponding to the input parameters associated with the payload data and the overhead data;
a packet assembler for receiving data from one or more TDM time-slots, along with the parameter k and one or more of the input parameters, and producing one or more data packets each having k multiframes of TDM data.
8. A system according to claim 7 , wherein the processor calculates the parameter k such that
k
=
Ceiling
[
-
OH
(
-
MN
mx
ⅇ
1
/
τ
+
MN
mx
ⅇ
n
/
τ
+
EF
1
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mx
ⅇ
1
/
τ
+
EF
1
OHⅇ
1
/
τ
)
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MN
mx
ⅇ
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/
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+
EF
1
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mx
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1
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τ
-
OHⅇ
n
/
τ
+
EF
1
OHⅇ
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τ
)
]
,
the input parameters including OH, M, N mx , τ, n, EF 1 , wherein:
OH represents an amount of packet overhead data;
M represents an amount of frames in a signaling multiframe of the TDM data;
N mx represents a maximum amount of times slots per frame associated with the TDM data;
τ represents a time constant;
n represents an amount of time-slots associated with the TDM data;
EF 1 represents a minimum allowed efficiency of the data packet;
and Ceiling[ ] represents a function for limiting the parameter k to an integer value.
9. A system according to claim 7 , wherein the TDM data includes T1 data.
10. A system according to claim 7 wherein the TDM data includes E1 data.
11. A system according to claim 7 , wherein the packet includes a header, and the TDM data is delineated such that a first byte in a signaling multiframe is directly adjacent to the header.
12. A system according to claim 11 , wherein the header includes an RTP header.
13. A system according to claim 12 , wherein the RTP header includes an extended RTP header having data associated with (i) starting time-slot, (ii) number of time-slots per frame, and (iii) number of multiframes in the data packet.
14. A system according to claim 11 , wherein the signaling multiframe corresponds to a multiframe associated with the TDM data.
15. A system according to claim 14 , wherein the multiframe includes 16 frames for E1 data.
16. A system according to claim 14 , wherein the multiframe includes 24 frames for T1 data.
17. A system according to claim 7 , further including a switch for receiving (i) the parameter k from the processor, (ii) a user-defined parameter k, and (iii) a switch control signal, wherein the switch provides, to the packet assembler, either the parameter k from the processor or the user-defined parameter k, as a function of the switch control signal.