Attack tests

Securing the cooperative ITS should not have negative effect on the normal system operation and, therefore, the security functions introduced by PRESERVE should be transparent to the nmning applications and facilities. The functional tests described in the previous section aims to evaluate the correctness and the performances of those functions under normal conditions, while in this section we describe the test case that includes the presence of an adversary. 

An extra payload that carries the security header is added to the messages, and a processing delay is expected for the generation and verification of such a payload. We consider the case where the attacker tries to exploit this delay and attempts to temporarily or indefinitely interrapt or suspend services of an ITS-enabled host. To be able to achieve this goal, the attacker usually saturates the target machine with messages that require computation on the receiver side, so much so that it cannot process the legitimate traffic. Such an attack leads to host overload , and therefore we address this adversary as the Overload Attacker . 

The adversary saturates the target maehine by foreing the consumption of computational resources, such as bandwidth or processor time. When using the security functionalities, those two resources are directly related the more messages that are received, the more processing time is required. Therefore, the overload attacker needs to send data faster than the receiver is able to process. 

During the normal operations, we enable an outsider ITS station to act as the overload attacker with the modified PRESERVE VSS. This device then starts broadcasting invalid messages to other ITS stations at a rate of 1,000 Hz. We then evaluate the impact of such an attack on the system by comparing the measurements of the packet processing time in the normal operations with the ones obtained during 

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The formation of crevices between dissimilar metals should be avoided. Corrosion at such connections is generally more severe than either galvanic or crevice corrosion alone. Also, crevices between metals and certain types of plastics or elastomers may induce accelerated rates of combined crevice and chemical attack. Testing is recommended prior to establishing final design specifications. 

The attack test results are tabulated in Table 2. Corresponding to Table 2, we have the observations blow ... 

The hydrolytic resistance test described in this chapter is the powdered glass test and not the water attack test as described above see Appendix <661>, USP 27 [1]. 

For the four types of glasses, there are designated relevant test types and expected limits. These are provided in Table 3. USP has provided procedure and test requirements for three types of tests. These are the powdered glass test, the water attack test, and the... 

The second chemical resistance test, the water attack test, is exclusively used for Type II glass because its properties come from a coating that would not be represented if powdered. In this test, containers... 

A testing method developed in Great Britain (RARDE Fragment Attack Test) (Barker et al., 1985) will be described here. 

Tab 5 chemical attack test of tantalum and tantalum-boride... 

Drip Course. A protruding or recessed course inside the crown of a glass tank, to prevent molten material running down and corroding the breast walls. Drip Test. See slag attack tests. Drop Arch. An auxiliary brick arch projecting below the general inner... 

Pilkington Bros. Ltd., England, in 1937. (For a more recent process introduced by this firm see float glass process.) Pill Test. See slag attack tests. Pillar. (1) A column of brickwork for example the refractory brickwork between the doors of an open-hearth steel furnace. 

Rotary Disk Feeder. See disk feeder. Rotary Drum Test. See slag attack TESTS. 

Slag Attack Tests. Refractories are attacked by the corrosive slags formed during metallurgical processes. Various simulative tests have been devised to assess the resistance of refractories to slag attack. 

Corrosion tests are performed to evaluate potential impacts on steel or concrete structures due to chemical attack. Tests to evaluate corrosion potential include resistivity, pH, sulfate content, and chloride content. 

The suitability of a rubber for use in contact with an oil or chemical is thus assessed hy immersing a sample in fluid and measuring the resulting increase in weight or volume. Such tests represent more severe conditions than are generally encountered in actual service, since few commercial seals are immersed for longer than 24 h and, even flien, only partial immersion is likely. In actual use, only a part of the seal s surface area is exposed to fluid attack. Tests have shown that totally immersed test specimens swell three to six times more than those exposed to fluid on one surface only. It makes sense therefore that a stock may perform well in use, even though in total immersion tests the volume swell may he 100% or more. On the other hand, flie... 

The overview of the attack testing framework is provided in the next section. The details of the attack testing process is presented in Section 3. Section 4 presents the implementation and experiments. The related work are discussed in Section 5. Section 6 summarizes this work and future research directions. 

The rest of the framework consists of three major modules signature-base module, sensor module, and main module (see Section 3.1). The three modules form the architecture of the attack test driver. Signature-base module provides the executable attack test scenarios called attack signatures that are ready to be used for testing by the attack test driver. The attack signature generator is used to produce attack signatures from the modeled attack scenarios. 

The main module contains an attack testing engine (called IDSpec) that in general requires two types of parameters attack signatures and test driver specific system events. IDSpec tests the system based on the modeled attack scenarios and generates a report when an attack is found. 

The attack test driver consists of three principal modules (see Figure 2) signature-base, sensor, and main. The modules are discussed in the following paragraphs. 

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