Analytical Delay Model of virtual CPE for 5G eMBB services in SD-CDN

The high bandwidth and moderate latency requirements of enhanced Mobile BroadBand (eMBB) content in 5G are handled by Content Delivery Network (CDN) components such as customer premises equipment (CPE) in edge, branches in fog, and servers in the cloud. The indispensable goal of 5G network providers is meeting these requirements on the same physical component that reduces operational and capital expenditures (OPEX/CAPEX). However, we've believed that different configuration policies of providers can be only handled by Software-Defined CDN (SD-CDN). Moreover; due to the flow characteristics of eMBB and handling packet forwarding by only software-based component in an OpenFlow (OF) switch, obtained packet processing delay in conventional CPE has become challenging. Therefore, we propose SD-vCPE with a novel physical block diagram which includes hardware and software-based OF tables. The analytical models of conventional and SD-vCPE are also derived by using G/G/1 Markov queues, considering general eMBB flow characteristics, and SpeedUp parameters in the software part. According to analytical and simulation results, as the resolution of video content in eMBB is increased, the conventional CPE cannot handle delay in the microsecond level; whereas, proposed SD-vCPE outputs approximately 1-millisecond decrease on packet delay which differentiates according to matching rules in TCAM or CPU. Namely, the proposed analytical model for SD-vCPE results in a delay in an acceptable rate while comparing the simulation results performed in MATLAB.