Metadata-Aware Memory Security

Cloud computing reduces infrastructure costs by allowing applications to run on shared servers, but it introduces critical memory security challenges, as users lack control over the underlying hardware and the software co-residing on the same server. One security challenge is physical attacks on memory, such as memory bus snooping, which is addressed through hardware-based memory encryption. While effective, encryption often causes significant time (performance) overhead, especially for irregular workloads. Another challenge is side channels caused by memory sharing, where attackers infer sensitive data through cache or DRAM reuse. As a result, cloud providers often disable memory sharing, sacrificing space (capacity) for security. This thesis focuses on reducing the cost of cloud memory security by optimizing metadata management. It minimizes the time overhead of memory encryption by improving how encryption-related metadata (e.g., write counters) is encoded and accessed. It also addresses the space overhead of memory isolation by novel coding of metadata for memory sharing - physical page number (PPN) of shared page, enabling secure memory sharing without sacrificing efficiency. By managing both types of metadata intelligently, this work reduces the time and space costs of secure cloud memory, offering practical solutions for efficient and secure cloud systems.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Computer Science & Applications

Department dc:contributor.department

Computer Science and#38; Applications

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2025

Author dc:creator

• Wang, Xin

Chair dc:contributor.committeechair

• Jian, Xun

Committee members dc:contributor.committeemember

• Nikolopoulos, Dimitrios S.
• Yao, Danfeng
• Jung, Changhee
• Hicks, Matthew

• Memory Security
• Cache
• Memory
• Computer Architecture.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

vt_gsexam:44377

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/136969