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The construction of the test environment

Core and principle of test environment construction: 1. Check whether the optical power exists Generally use optical power to test whether there is optical power; And the optical power of some ophthalmograms is -2dbm, -3dbm, etc. 2. Whether the clock is accurate The clock is the reference infor... Read More

Light eye map basic explanation II

A deep interpretation of jitter If the data rate of the system is increased, the jitter amplitude measured in a few seconds will remain roughly the same, but when measured in a fraction of the time of the bit period, it will increase proportionately with the data rate, resulting in bit errors. Th... Read More

tcpreplay Stream Test Method

Test schematic diagram: System version: Ubuntu16.04 Tcpreplay installation: apt-get install tcpreplay (This version of the NIC name is not called eth0 and eth1, the following configuration changes) eth0 corresponds to ens33 NIC: IP: 172.20.60.166 MAC: ec:a8:6b:82:32:c1 eth1 corresponds to th... Read More

Nirtual local area network

A virtual local Area Network (VLAN) is a communication technology that divides a physical LAN into multiple broadcast domains logically. ​ Each VLAN is a broadcast domain. Hosts within a VLAN can directly communicate with each other, but cannot directly communicate with each other. In this way, b... Read More

Two basic concepts of lasers

Two basic concepts of laser, one is stimulated emission, the other is the resonator. In this paper, the basic principle of DBR (Distributed Bragg Reflector), which is a resonator in VCSEL type lasers, is introduced. Two basic physics knowledge: reflection phase transition and thin film interferen... Read More

Related ports on the switch

Users belonging to the same VLAN on the live network may be connected to different switches, and there may be more than one VLAN across the switch. To communicate with users, interfaces between switches must be able to identify and send data frames of multiple vlans at the same time. According to... Read More