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With the development of the global communication, new technologies such as 5G, SDN/NFV, mobile internet, cloud computing, internet of things, big data and so on are coming forth rapidly. In the phase of R&D, manufacturing and maintenance about the communication products, the engineers should test and measure them. In this paper, we analyze the technology and product architecture in the field of wireless and wired communication test and measurement. We study some famous communication test and measurement companies, such as R&S, Keysight, Anritsu and Aeroflex in the field of wireless communication test and measurement, Spirent, IXIA and Fluke in the field of wired communication test and measurement. Finally, we give some hot topics about the future communication test and measurement in the next 5 to 10 years.

This paper designs an efficient channel mismatch calibration method for TIADC (time-interleaved analog-to-digital converter) system, in order to reduce the complexity and inefficiency of the conventional correction methods. Based on the principle of equivalent sampling, the sampling data of a certain number of cycles is overlapped to one cycle high-resolution data, from which all parameters needed to correct channel mismatch, such as average value, amplitude range and phase, can be acquired, so the calibration of the offset mismatch, gain mismatch and time mismatch can be realized at the same time, avoiding the great calculation of FFT or curve fitting. By normalizing the three parameters, these channels can be turned into points in the three dimensional space, the point with smallest distance sum respected to all the other points can be chosen as the reference channel, the calibration time is reduced consequently. Simulation and application results show that the method can measure above-mentioned errors rightly and enhance the performance of TIADC efficiently, at the same time, reduces the complexity and calculation.

Packet classification has been the core component of current Internet architecture, and ternary content addressable memory (TCAM) has become the de facto standard for performing high-speed packet classification. Unfortunately, TCAM has limitations such as small capacity and high power consumption. Therefore, how to improve memory usage and decrease power consumption are crucial to TCAM-based technologies. In this paper, we propose a space-efficient TCAM-based packet classification scheme called TCAM-PC, which decreases TCAM memory consumption by compressing the space for the same information parts embedded in different rules, and guarantees a predetermined packet forwarding rate based on the cooperation between the global mask register and block mask register in a TCAM. Performance analysis shows TCAM-PC can achieve smaller memory requirement and higher memory utilization while guaranteeing a high-speed packet forwarding rate. To the best of our knowledge, this is the first attempt to adaptively compress the TCAM space while guaranteeing a high packet forwarding rate.

We consider a distributed hybrid search scheme for peer-to-peer network in this paper and introduce one link statement function, which is decreasing with the round trip time (RTT) of link. Link statement function is reasonable because they can reflect how well the link worked, for example, overloaded or not. The transition probability function between two nodes is redefined, which depend on not only the association of these two nodes but also the link statement between them. So one node can choose its best neighbor based on the transition probability between them to forward the query message. This algorithm is more robust and adaptive to the dynamic networks.

Skip Graphs provide novel distributed data structures for peer-to-peer (P2P) searching. They are simple, resilient and are capable of supporting complex queries. Like many distributed hash table (DHT) algorithms, one issue that remains to be addressed is the large number of pointers per node in the system. They suffer from the problems of high storage requirements and high volume of repair-mechanism message traffic. In addition, nodes are treated equally in Skip Graphs, but empirical studies have shown that peers in P2P networks are heterogeneous. Some nodes are more powerful and stable than the others. In order to solve these problems, we propose the Skip Graphs++, which gives an adaptive node capacity model to evaluate the performance of nodes in the system and builds the relationship between the loads and the capacities of nodes. In Skip Graphs++ system the loads are proportional to the capacities of nodes. Powerful nodes afford more loads and weak nodes afford fewer loads. Theoretical and experimental results have shown that the maintenance overhead is reduced efficiently via heterogeneity.