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Multi-access edge computing (MEC) is a key technology for enabling various services in 5G applications. Existing works mainly focus on the key technologies of MEC. In this article, we, as a mobile operator, share our experience with a self-developed MEC system, called 5G Intelligent A+, for 5G private networks. This system is inline and transparent, and is located between the base station (BS) and the mobile core network. Therefore, it is not affected by changes in the BS and core network, and does not require pre-configuration. We demonstrate the key functions of the system, including versatile conditions for local breakout, flexible network access management, on-demand bandwidth allocation based on mobile subscriber ISDN number, time, and location. We also show how to support inter-region access via an innovative tunneling mechanism called tunnel MEC (T-MEC). We then demonstrate that the system can efficiently provide enterprises with diverse services, which can be performed online and in real time. This MEC system works well with many types of access networks and is applicable to non-standalone and standalone (SA) 5G networks. The proof of concept has been tested in Taiwan to prove the flexibility and usability of the MEC system. In addition, some functions and applications were also demonstrated at the Mobile World Congress 2018 and 2019.

In this paper, we develop a stream-based system, CoreView (CV) having launched at Chunghwa Telecom in Taiwan, that characterizes with T-connection or non-intrusion and is based on the mobile network signalling, to support mobile network diagnosis and comprehensive location services simultaneously in near real-time. With the CV-network diagnosis, can operators have expertized systems and save the expenses for the network maintenance. In addition, they have opportunity to enhance the profitability with the CV-location services.

A new method for small displacement measurement based on surface plasmon resonance and heterodyne interferometry is presented. A heterodyne light is focused on a mirror and reflected from it, and then it is incident on a prism which was coated with a thin gold film. When the mirror or the objective lens has a small displacement, the light will be converging or diverging into the prism, and the phase variation between two parts of the test beam under the condition of surface plasmon resonance (SPR) can be measured by using a two-segment photodiode and a lock-in amplifier. This phase difference between two parts of the test beam is proportional to the departure of the mirror from the focal plane, so the displacement can be obtained in real-time. It has some merits, such as, simple, stable, very high sensitivity and resolution. And its resolution is better than 1nm.

-- For improving the sensitivity of a D-type SPR fiber sensor, we simulated the optimum parameters , such as, the thickness of coatings, the length of sensor, and the angle of incidence for different ranges of refractive index. These simulations are based on SPR theory and the intensity and phase methods. It is clearly that, the sensitivity is improved by increasing the length of sensor and/or the thickness of the gold film. And the sensitivity of the phase method is higher than the intensity method by two orders. It is used to detect the refractive index or concentration of gas or liquid in real-time, and it has some merits, such as, small, simple, cheaper, and in vivo test. Keywords : surface plasmon resonance (SPR), fiber sensor 1. INTRODUCTION SPR fiber sensor is very useful in many applications in resent years 1-4 , such as, physical, chemical, biophotonics, etc. Although the sensitivity is not as high as that of the SPR prism sensor, however, owing to its merits such as, low cost, smaller tested volume, convenient to operation, in-vivo testing, it is also attention-getting in the future. There are several types of optical fiber sensor (OFS) based on surface plasmon resonance had been proposed

For improving the sensitivity of a SPR biosensor, we proposed a new combination of the thin silver (Ag) and SiO 2 films, and used the common-path heterodyne interferometry. Although the Ag film has higher sensitivity than the gold (Au) film 1 , but Ag has toxicity for many media and it is easy to be oxidized. In order to enhance the sensitivity and protect the tested medium not to directly contact with Ag, we selected a coating of SiO 2 on the Ag film for the reason of it is cheaper and easy to obtain. The simulations and experimental results are shown that its best resolution could reach to the value of 6.9×10 -9 RIU.

We propose an MPLS switch with a GPS-based scheduler to provide guaranteed QoS in the Internet. The considered scenarios include cases with sufficient labels or with a limited number of labels under competing streams. Due to tractability issues in direct analysis, we use a worst case equivalent system model to obtain the theoretical upper bounds of delays and backlogs of the original system model. Simulation results are used to verify the analytical results. We can obtain the worst case delay bounds and the maximum backlogs. Furthermore, the trade-off among the number of labels, the worst delay bounds, and the maximum backlogs can be observed. With our model, one can determine the number of required labels according to the allowable delay and the available buffer size.

The performance of a GMPLS (generalized multiprotocol label switching) architecture with flush capability is studied. For this switching architecture, we propose a queueing model that includes the control plane, the switching buffer mechanism, and the flush mechanism. The flush capability is included to reduce the out-of-sequence problem due to dynamic path changes. The behavior of aggregated streams, the label-setup and release policies, and the mechanisms for efficient resource allocation are all covered. With the proposed model, one can select appropriate parameters for the label-setup policy and the label-release policy to match the traffic load and network environment. Key performance metrics, such as throughput, label-setup rate, and fast path bandwidth utilization, can all be evaluated by this mathematical model. Numerical results and simulations are used to verify the accuracy of our proposed queueing model. Finally, the trade-off among these performance metrics can be observed as well.

The CDMA with packet reservations for local wireless voice communications is addressed. The reserved channel resource for each active user is a pseudo-noise code over a particular time slot. A two-mode reservation process is introduced. The probability of packet dropping is derived for performance evaluations. Results of numerical examples are presented to illustrate and compare the performances for different cases.

We propose a close-loop queueing model of a multiprotocol label switching (MPLS) switch with the different label-setup and release policies, supporting both traffic-driven and topology-driven connection setup procedures. This model can emulate the behavior of TCP under the MPLS switch when the maximum window size is sustained and the packet loss rate is negligible. From the proposed flow-based MPLS switch model, one can clearly observe the competition of multiple IP flow for limited labels, and how the label-setup policy and the label release policy affect the system performance. We find that Norton's theorem can be applied to solve this sophisticated queueing model. Therefore, with very limited computational complexity with respect to the number of IP flows or labels, the proposed mathematical model and the approximation of label competition can be used to obtain the desired performance metrics, such as the throughput, the label-setup rate, and the channel utilization. Finally, the trade-off among performance metrics can be observed as well.

This paper proposes a queueing model including the control plane and the switching buffer mechanism of a GMPLS switch for evaluating the performance of a GMPLS switching architecture. With the proposed model, one can select appropriate parameters for the label-setup policy and the label-release policy to match the traffic load and network environment. Key performance metrics, including the throughput, the label-setup rate, and the fast path bandwidth utilization can be obtained via the analytical results. Numerical results and simulations are used to verify the accuracy of our proposed queueing model. The trade-off among these performance metrics can be observed as well.