3 research outputs found
Cloud-Aided Interference Management with Cache-Enabled Edge Nodes and Users
This paper considers a cloud-RAN architecture with cache-enabled
multi-antenna Edge Nodes (ENs) that deliver content to cache-enabled end-users.
The ENs are connected to a central server via limited-capacity fronthaul links,
and, based on the information received from the central server and the cached
contents, they transmit on the shared wireless medium to satisfy users'
requests. By leveraging cooperative transmission as enabled by ENs' caches and
fronthaul links, as well as multicasting opportunities provided by users'
caches, a close-to-optimal caching and delivery scheme is proposed. As a
result, the minimum Normalized Delivery Time (NDT), a high-SNR measure of
delivery latency, is characterized to within a multiplicative constant gap of
under the assumption of uncoded caching and fronthaul transmission, and
of one-shot linear precoding. This result demonstrates the interplay among
fronthaul links capacity, ENs' caches, and end-users' caches in minimizing the
content delivery time.Comment: 9 pages, 3 figures, submitte
How Much Can D2D Communication Reduce Content Delivery Latency in Fog Networks with Edge Caching?
A Fog-Radio Access Network (F-RAN) is studied in which cache-enabled Edge
Nodes (ENs) with dedicated fronthaul connections to the cloud aim at delivering
contents to mobile users. Using an information-theoretic approach, this work
tackles the problem of quantifying the potential latency reduction that can be
obtained by enabling Device-to-Device (D2D) communication over out-of-band
broadcast links. Following prior work, the Normalized Delivery Time (NDT) --- a
metric that captures the high signal-to-noise ratio worst-case latency --- is
adopted as the performance criterion of interest. Joint edge caching, downlink
transmission, and D2D communication policies based on compress-and-forward are
proposed that are shown to be information-theoretically optimal to within a
constant multiplicative factor of two for all values of the problem parameters,
and to achieve the minimum NDT for a number of special cases. The analysis
provides insights on the role of D2D cooperation in improving the delivery
latency.Comment: Submitted to the IEEE Transactions on Communication