CN103269256A - Information timeliness safety judgment method in safety coding communication system - Google Patents

Abstract

The invention relates to an information timeliness safety judgment method in a safety coding communication system. The method comprises the steps that (1) the system initializes a timestamp T(0) and code data M(0) corresponding to the timestamp; (2) the system updates the timestamp and the code data corresponding to the timestamp every cycle; (3) a network communication node END1 transmits a timestamp T(i) and code data M(i) corresponding to the timestamp to a network communication node END2; (4) END2 packs and replays the timestamp and the code data corresponding to the timestamp to the END1, wherein the timestamp and the code data corresponding to the timestamp are transmitted by the END1; (5) after the END1 receives the package, an information timeliness check word is generated and is transmitted to a third party to be judged according to the timestamp and the code data corresponding to the timestamp in the package, and a current timestamp T(n) and code data M(n) corresponding to the current timestamp T(n). Compared with the prior art, the information timeliness safety judgment method in the safety coding communication system has the advantages of being low in complexity, low in time consumption, safe, reliable and the like.

Description

The ageing safe determination methods of message in the safe coding communication system

Technical field

The present invention relates to information security field in the communication system, especially relate to the ageing safe determination methods of message in a kind of safe coding communication system.

Background technology

In communication system, often need carry out safe judgement to communication information is ageing, most of communication systems add local and remote timestamp and judge that message is ageing in message body, this method can meet the demands in non-safety system, but in subsystem and this class safety system of interlock system that the safe input and output of subway onboard system are controlled, can not satisfy security requirement.In subsystem and interlock system that the safe input and output of subway onboard system are controlled, secure data all is Boolean quantity, in order to guarantee safety, system is encoded to 32 redundant datas that meet certain algorithm to Boolean quantity, but the characteristics of these two kinds of systems are to carry out safe coding and can not encode to integer quantity Boolean variable.

Summary of the invention

Purpose of the present invention is exactly to provide the ageing safe determination methods of message in the safe coding communication system that a kind of complexity is low, time loss is low and safe and reliable for the defective that overcomes above-mentioned prior art existence.

Purpose of the present invention can be achieved through the following technical solutions:

The ageing safe determination methods of message in a kind of safe coding communication system is characterized in that this method may further comprise the steps:

(1) system initialization time stamp T (0) and this timestamp corresponding codes data M (0);

(2) system stabs and timestamp corresponding codes data each update time in cycle;

(3) network communication node END1 issues network communication node END2 with time stamp T (i) and this timestamp corresponding codes data M (i);

(4) END2 timestamp that END1 is sent and corresponding codes data are packed and are replied to END1;

(5) after END1 received this bag, timestamp and corresponding codes data and current time stamp T (n) and corresponding codes data M (n) according in the bag generated an ageing check word of message and issue the third party and judge.

Described coded data is 32 signless integer.

System in the described step (2) stabs each update time in cycle, is timestamp and adds 1 renewal, T (i)=T (i-1)+1.

The corresponding codes data are stabbed each update time in cycle by system in the described step (2), namely $M\left(i\right)=M(i-1)\widetilde{+}0,$ Wherein

Expression PD computing.

The ageing check word of message of generation in the described step (5) may further comprise the steps:

1) at first carry out non-safety and judge, D=T (n)-T (i) is if D not within the term of validity, then loses end of message subsequent step, otherwise carries out 2);

2) constant M of the first XOR of M (i), i.e. M (i)=M (i) ^M, executable operations then $M\left(i\right)=M\left(i\right){\left(\widetilde{+}\right)}^{D}0,$ At this moment $M\left(i\right)=M\left(n\right)^\left(M{\left(\widetilde{+}\right)}^{D}0\right),$ Symbol " ^ " expression XOR, symbol

Expression PD computing, i.e. polynomial division computing, symbol

The operand on expression the right and the operand on the left side carry out D PD computing;

3) generate intermediate variable $V=M\left(i\right)^M\left(n\right)=(M\left(n\right)^\left(M{\left(\widetilde{+}\right)}^{D}0\right))^M\left(n\right)=M{\left(\widetilde{+}\right)}^{D}0;$

4) predefine correction value constant array A[D], V and A[D] calculate the check word by polynomial division, namely $\mathrm{CHKW}=V\widetilde{+}A\left[D\right].$

Compared with prior art, the present invention has the following advantages:

1, judges earlier whether the message that receives satisfies the ageing check word that calculates this message after the ageing requirement again, effectively reduces time waste, reduces complexity; It is effective time value 4 that the D=5 value has surpassed definition, but when judging, think still effectively, the correction value that get this moment is A[5], at this moment will make mistakes, because effectively the correction value number equals effective time value of system definition, A[5] be exactly a unexpected number, therefore the check word that calculates is wrong

2, adopt the third party that the check word that generates is judged, reduce ageing judgement error rate, guarantee the safety of output.

Description of drawings

Fig. 1 is the system block diagram of the embodiment of the invention.

Fig. 2 is the main flow chart of the inventive method.

Fig. 3 generates the flow chart that timeliness is checked word for the present invention.

Embodiment

The present invention is described in detail below in conjunction with the drawings and specific embodiments.

Fig. 1 is structured flowchart of the present invention, I is network communication node END1, II is the network data that I sends, III is network communication node END2, IV is that the III end is to the processing module of the network data of reception, V is the network data that III sends, and VI is that the I end calculates the ageing check word modules of message, and VII is the device of the check word of verification I end generation.

As shown in Figure 2, the ageing safe determination methods of message may further comprise the steps in a kind of safe coding communication system:

Step 101: the time stamp T (0)=0 that system initialization is initial and this timestamp corresponding codes data M (0), coded data is 32 signless integer, and loads correction value constant array A;

Step 102: system stabs each update time in cycle, and timestamp adds 1 to be upgraded, i.e. T (i)=T (i-1)+1;

Step 103: the corresponding codes data are stabbed each update time in cycle by system, namely

Wherein

The computing of expression polynomial division;

Step 104: network communication node END1 issues network communication node END2 with time stamp T (i) and this timestamp corresponding codes data M (i);

The timestamp that step 105:END2 sends END1 and corresponding codes data are packed and are replied to END1;

After step 106:END1 receives this bag, according to time stamp T (i)=6 and corresponding codes data M (i) and current time stamp T (n)=8 and the corresponding codes data M (n) in the bag, calculate and generate the ageing check word of message;

Step 107: will check word and issue the third party and judge, if make mistakes just export orientation safety;

Step 108: return step 102 and continue to carry out.

As shown in Figure 3, the ageing check word of message of the described generation of step 106 may further comprise the steps:

Step 201: at first carry out non-safety and judge, D=T (n)-T (i)=2, the message term of validity that supposing the system is set is that 4, D is not more than 4, then execution in step 202, otherwise execution in step 205;

Constant M of the first XOR of step 202:M (i), i.e. M (i)=M (i) ^M, executable operations then $M\left(i\right)=M\left(i\right){\left(\widetilde{+}\right)}^{D}0,$ At this moment $M\left(i\right)=M\left(n\right)^\left(M{\left(\widetilde{+}\right)}^{D}0\right),$ Symbol " ^ " expression XOR, symbol

Expression PD computing, i.e. polynomial division computing, symbol

The operand on expression the right and the operand on the left side carry out D PD computing;

Step 203: generate intermediate variable

$V=M\left(i\right)^M\left(n\right)=(M\left(n\right)^\left(M{\left(\widetilde{+}\right)}^{D}0\right))^M\left(n\right)=M{\left(\widetilde{+}\right)}^{D}0;$

Step 204:V and A calculate the check word by polynomial division, namely

Turn to step 206;

Step 205: if D exceeds the term of validity, show that this message is overtime, should lose, and carry out relevant safety operation according to using.

Step 206: finish.

Claims (5)

1. the ageing safe determination methods of message in the safe coding communication system is characterized in that this method may further comprise the steps:

(1) system initialization time stamp T (0) and this timestamp corresponding codes data M (0);

(2) system stabs and timestamp corresponding codes data each update time in cycle;

(3) network communication node END1 issues network communication node END2 with time stamp T (i) and this timestamp corresponding codes data M (i);

(4) END2 timestamp that END1 is sent and corresponding codes data are packed and are replied to END1;

(5) after END1 received this bag, timestamp and corresponding codes data and current time stamp T (n) and corresponding codes data M (n) according in the bag generated an ageing check word of message and issue the third party and judge.

2. the ageing safe determination methods of message in a kind of safe coding communication system according to claim 1 is characterized in that described coded data is 32 signless integer.

3. the ageing safe determination methods of message in a kind of safe coding communication system according to claim 1 is characterized in that, the system in the described step (2) stabs each update time in cycle, is timestamp and adds 1 renewal, T (i)=T (i-1)+1.

4. the ageing safe determination methods of message in a kind of safe coding communication system according to claim 1 is characterized in that, the corresponding codes data are stabbed each update time in cycle by the system in the described step (2), namely $M\left(i\right)=M(i-1)\widetilde{+}0,$ Wherein

Expression PD computing.

5. the ageing safe determination methods of message in a kind of safe coding communication system according to claim 1 is characterized in that, the ageing check word of message of the generation in the described step (5) may further comprise the steps:

1) at first carry out non-safety and judge, D=T (n)-T (i) is if D not within the term of validity, then loses end of message subsequent step, otherwise carries out 2);

2) constant M of the first XOR of M (i), i.e. M (i)=M (i) ^M, executable operations then $M\left(i\right)=M\left(i\right){\left(\widetilde{+}\right)}^{D}0,$ At this moment $M\left(i\right)=M\left(n\right)^\left(M{\left(\widetilde{+}\right)}^{D}0\right),$ Symbol " ^ " expression XOR, symbol

Expression PD computing, i.e. polynomial division computing, symbol

The operand on expression the right and the operand on the left side carry out D PD computing;

3) generate intermediate variable $V=M\left(i\right)^M\left(n\right)=(M\left(n\right)^\left(M{\left(\widetilde{+}\right)}^{D}0\right))^M\left(n\right)=M{\left(\widetilde{+}\right)}^{D}0;$

4) predefine correction value constant array A[D], V and A[D] calculate the check word by polynomial division, namely $\mathrm{CHKW}=V\widetilde{+}A\left[D\right].$

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