Anti-irradiation protection method for TCAM of space devices

Abstract

The invention discloses an anti-irradiation protection method for a Ternary Content Addressable Memory (TCAM) of space devices, characterized by firstly constructing a TCAM anti-irradiation protection system comprising a refresh cycle calculating module, a refresh control module, an ECC coding module, and an ECC decoding error correction module, wherein the refresh cycle calculating module determines a refresh cycle value tsp, the refresh control module conducts the refresh control of RAM according to the tsp, and the ECC decoding error correction module carries out decoding error correction on the data read from the RAM; when the ECC coding module receives XWE of refresh control logic, the ECC coding module writes the data into the RAM, if the ECC coding module does not receive the XWE, the ECC coding module receives the data processed by decoding and error correction sent by the ECC decoding error correction module and carrying out ECC coding on the data again. According to the invention, there is no need to connect a special coding circuit for TCAM internal connection, the frequent refresh of TCAM is prevented, the error correction of error data is realized, and the problem of data anti-irradiation storage protection of TCAM devices in outer space is effectively solved.

Description

technical field [0001] The invention relates to an anti-radiation protection method for TCAM (Ternary Content Addressable Memory) of space equipment in a space network. Background technique [0002] At present, a large number of space devices oriented to network and information security, including firewalls, forwarding tables, and coprocessors, are mainly implemented with TCAM. However, due to the existence of a large number of alpha particles, heavy ions and other particles in the space environment, the radiation and impact caused by them will have a greater impact on the electronic equipment running in space, causing TCAM to produce a single event flip. Once a single-event flip occurs in the TCAM, the information stored inside it will be wrong, which will have an important impact on the space network and information security. [0003] The TCAM storage unit has three storage states of logic "0", logic "1" and logic "X". In the process of data storage, a TCAM storage unit ...

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Problems solved by technology

[0008] The disadvantage of this method is that the structure of the TCAM circuit is complicated, and it is necessary to additionally design a redundant error correction coding circuit inside the TCAM circuit (due to the existence of SEC); if the redundant error correction coding SEC is adopted, some storage bytes will be required to store the correction code. Position verification reduces the coding rate; the literature only theoretically studies the refresh fault tolerance of TCAM, and does not describe how to implement it in engineering

The disadvantage is that the refresh cycle of embedded DRAM is only determined by the DRAM process design and cannot be dynamically adjusted

If the refresh cycle value is too large, the probability of errors will increase; if the refresh cycle value is too small, the TCAM will be written too frequently, which will reduce the matching efficiency in the TCAM search process.

[0010] Combining the two methods of redundant code error correction and refreshing, the fault-tolerant design of TCAM can improve its anti-irradiation performance, so far there is no public literature related to

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