Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: New Attacks and Defenses for Randomized Caches   The last level cache is vulnerable to timing based side channel attacks
because it is shared by the attacker and the victim processes even if they are
located on different cores. These timing attacks evict the victim cache lines
using small conflict groups(SCG), and monitor the cache to observe when the
victim uses these cache lines again. A conflict group is a collection of cache
lines which will evict the target cache line. Randomization is often used by
defenses to prevent creation of SCGs.
  We introduce new attacks to demonstrate that the current randomization
schemes require an extremely high refresh rate to be secure, on average a 15\%
performance overhead, and upto 50\% in the worst case. Next, we propose a new
randomization strategy using an indirection table, which mitigates this issue.
Addresses of cache lines are encrypted and used to lookup the indirection table
entry. Each indirection table entry stores a mapping to a randomly chosen cache
set. The cache line is placed into this randomly chosen set. The encryption key
changes upto 50x faster than CEASER's default rate, by using evictions to
trigger the re-randomization. Instead of moving cache lines, this mechanism
re-randomizes one iTable entry at a time, whenever the cache lines
corresponding to the iTable entry are naturally evicted. Thus, the miss rate is
not much worse than the baseline.
  We quantitatively show that our scheme does almost as well as a fully
associative cache to defend against these attacks. We also demonstrate new
attacks that target the iTable by oversubscribing its entries, and
quantitatively show that our scheme is resilient against new attacks for
trillions of years. We estimate low area ( < 7\%) and power overhead compared
to a baseline inclusive last-level cache. Lastly, we evaluate a low performance
overhead (<4%) using the SPECrate 2017 and PARSEC 3.0 benchmarks.

23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph