The highly anticipated 5G mmWave technology promises to enable
many uplink-oriented, latency-critical applications (LCAs) such as
Augmented Reality and Connected Autonomous Vehicles. Nonetheless,
recent measurement studies have largely focused on its downlink
performance. In thiswork,we perform a systematic study of the
uplink performance of commercial 5G mmWave networks across
3 major US cities and 2 mobile operators. Our study makes three
contributions. (1) It reveals that 5G mmWave uplink performance
is geographically diverse, substantially higher over LTE in terms of
bandwidth and latency, but often erratic and suboptimal, which can
degrade LCA performance. (2) Our analysis of control messages
and PHY-level KPIs shows that the root causes for the suboptimal
performance are fundamental to 5G mmWave and cannot be easily
fixed via simple tuning of network configurations. (3) We identify
various design and deployment optimizations that 5G operators
can explore to bring 5G mmWave performance to the level needed
to ultimately support the LCAs.
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LDRP: Device-Centric Latency Diagnostic and Reduction for Cellular Networks Without Root
We design and implement LDRP , a device-based, standard-compliant solution to latency diagnosis and reduction in mobile networks without root privilege. LDRP takes a data-driven approach and works with a variety of latency-sensitive applications. After identifying elements in LTE uplink latency, we design LDRP that can infer the critical parameter used in data transmission and infer them for diagnosis. In addition, LDRP designates small dummy messages, which precede uplink data transmissions, thus eliminating latency elements due to power-saving, scheduling, etc. It imposes proper timing control among dummy messages and data packets to handle various conflicts. We achieve the latency diagnosis and reduction without requiring root privilege and ensure the latency is no worse than the legacy LTE design. The design of LDRP is also applicable for 5 G. The evaluation shows that, LDRP infers the latency with at most 4% error and reduces the median LTE uplink latency by a factor up to 7.4× (from 42 to 5 ms) for four apps over 4 mobile carriers.
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- Award ID(s):
- 1910150
- NSF-PAR ID:
- 10488002
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Mobile Computing
- ISSN:
- 1536-1233
- Page Range / eLocation ID:
- 1 to 17
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TMC.2023.3267805
