The space-efficiency of Bloom filters is achieved at the cost of a small, acceptable falsepositive
rate. Bloom filters were introduced into the IP traceback area by Snoeren et al. [33]
They built a system named the Source Path Isolation Engine (SPIE), which can trace
the origin of a single IP packet delivered by the network in the recent past. They
demonstrated that the system is effective, space-efficient, and implementable in current or
next-generation routing hardware. Bloom filters are used in each SPIE-equipped router to
record the digests of all packets received in the recent past. The digest of a packet is exactly
several hash values of its nonmutable IP header fields and the prefix of the payload.
Strayer et al. [34] extended this traceback architecture to IP-v6. However, the inherent false
positives of Bloom filters caused by unavoidable collisions restrain the effectiveness of
these systems. To reduce the impact of unavoidable collisions in Bloom filters, Zhang and
Guan [35] propose a topology-aware single-packet IP traceback system, namely TOPO.
The router’s local topology information, that is, its immediate predecessor information, is
utilized. The performance analysis shows that TOPO can reduce the number and scope of
unnecessary queries and significantly decrease false attributions. When Bloom filters are
used, it is difficult to decide their optimal control parameters a priori. They designed a
k-adaptive mechanism that can dynamically adjust the parameters of Bloom filters to
reduce the false-positive rate.
Shanmugasundaram et al. [36] proposed a payload attribution system (PAS) based on
a hierarchical Bloom filter (HBF). HBF is a Bloom filter in which an element is inserted
several times using different parts of the same element. Compared with SPIE, which is
a packet-digesting scheme, PAS uses only the payload excerpt of a packet. It is useful when
the packet header is unavailable.
Li et al. [37] proposed a Bloom filter-based IP traceback scheme that requires an order of
magnitude smaller processing and storage cost than SPIE, thereby being able to scale to
much higher link speed. The baseline idea of their approach is to sample and log a small
percentage of packets, and 1-bit packet marking is used in their sampling scheme. Therefore,
their traceback scheme combines packet marking and packet logging together. Their
simulation results showed that the traceback scheme can achieve high accuracy and scale
well to a large number of attackers. However, as the authors also pointed out, because of
the low sampling rate, their scheme is no longer capable of tracing one attacker with only one
packet.
Stepping-Stone Attack Attribution
Ever since the problem of detecting stepping stones was first proposed by Staniford-Chen and
Heberlein [38], several approaches have been proposed to detect encrypted stepping-stone
attacks.
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