Ethereum connection query
issued based on Ethereum public chain should be observed according to the price trend of the platform.
each version of Ethernet has a maximum cable length limit (that is, the length without amplification). Signals within this range can propagate normally, and signals beyond this range cannot propagate
in order to allow the construction of a larger network, repeaters can be used to connect multiple cables. Repeater is a physical layer device, which can receive, amplify and retransmit signals in two directions
extended data
several common Ethernet interface types
1. SC optical fiber interface
SC optical fiber interface has been applied in the era of 100base TX Ethernet, so it was called 100base FX at that time (F is the abbreviation of optical fiber). However, at that time, because the performance was not more prominent than twisted pair, but the cost was higher, so it was not popularized. Now the instry vigorously promotes gigabit network, and SC optical fiber interface is re valued
2. RJ-45 interface
this kind of interface is the most common network equipment interface, commonly known as "crystal head", and the professional term is RJ-45 connector, which belongs to the type of twisted pair Ethernet interface. RJ-45 plug can only be inserted along the fixed direction, and a plastic spring piece is set to be stuck with RJ-45 slot to prevent it from falling off
3. FDDI interface
FDDI has the highest transmission rate among the mature LAN technologies. It has the characteristics of timed token protocol, supports a variety of topologies, and its transmission medium is optical fiber. Fiber distributed data interface (FDDI) is a set of protocols developed by American National Organization for Standardization (ANSI) to transmit digital signals on optical cables
reference source: Network Ethernet interface
If you want to query the transaction records on the main network, you can use Etherscan. However, if you build your own private chain, how should you query the transaction records
the answer is that you need to listen to the logs on the chain, save them in the database, and then query them in the database. For example:
< pre t = "code" L = "Java" > varaddr = & quot& quot;< br />varfilter=web3.eth.filter({fromB lock:0 ,toBlock:' latest', address:addr });< br />filter.get(function(err,transactions){transactions.forEach(function(tx){
vartxInfo=web3.eth.getTransaction(tx.transactionHash);
/ / at this time, the transaction information txinfo can be stored in the database
})< br />});
Web3. Eth. Filter() is used to monitor the log on the chain, and Web3. Eth. Gettransaction() is used to extract the information of the specified transaction. Once the transaction information is obtained, it can be stored in the database for query
recommend a practical introction, you can see: Ethereum tutorial
you can't retrieve your assets through Ethereum block query
think too much
if you want to check the real estate,
you can go to the real estate transaction registration center.
After reading the answers of other respondents, I really want to laugh. It's not terrible to pretend that I don't understand. What's terrible is to answer blindly. There's something wrong with this question. The burst of 5.7 billion yuan has nothing to do with a drop of 10 cents. It can even be said that its disappearance is e to the sharp rise. So where is the decline? If bitcoin really falls, it will not be 5.7 billion capital washed away, it will be tens of billions, hundreds of billions of capital evaporated, those who talk about trends and development, please study the capital and stock market well, and by the way, please search for the meaning of the word "burst", no culture is too terrible
in addition, I would like to make a digression. Recently, a hot topic is fund. In 2021, the annual meeting is more or less a national fund. In 2020, the fund manager is still a good active fund. Even if the position is not changed, the annual yield will reach at least 40%, but this does not mean that this year is still OK, It's not that everyone can make money playing with funds. it's similar to the nature of stocks. Index funds, stock funds and even active funds are risky. I think many people say that they should get on the bus quickly. They are really worried about your funds of course, 2021 may be a bull market. It is estimated that the whole network has spread, many people are rubbing their hands to make a lot of money, but I can't do much. I just advise you not to go with the flow too much, don't be greedy, and don't think you are. That's all. Good luck
the Ministry of Ecation said that it will increase investment in art ecation this year and hold a National School Aesthetic Ecation Conference on the 21st< In recent years, Zhejiang, Anhui, Guangdong and other provinces have launched provincial environmental supervision, focusing on thermal power, steel, cement, glass, waste incineration and other instries
the Hang Seng ah premium index closed at 122.58, a new low in the last 10 months. Analysts believe that the ah share price gap will further narrow with the expansion of interconnection< It is estimated that the global gold demand and supply will rise by 1.5% and 0.5% respectively this year, and the gold price will break through in the second half of this year
04
major events
- the first digital China Construction Summit is about to be held in Hainan. We need to implement the strategy of
among the listed companies, gaoweida (300465) acquired 100% equity of Hainan nut creative Entertainment Information Technology Co., Ltd., which used big data analysis technology to build a mobile advertising platform characterized by hardware. Aofei data (300738) is the core provider of IDC (Internet Data Center Service), and Haikou Jinlu data center is under construction
● Alibaba's first shopping center will be opened soon, and the online and offline shopping centers will be fully integrated
the third phase of qinchengli shopping center in Hangzhou Xixi park will be officially opened on April 28. This is the first shopping center of Ali's new retail, which records consumers' purchase preferences through collection and storage. At the same time, Ali will implement new technologies such as "face brushing consumption", "zero burden shopping", "ar shopping guide" and "thousands of people and thousands of noodles" magic fitting in this project, so as to realize a new mode of online integration and offline (Omo), All brands of the shopping center are jointly operated online and offline to explore new retail brands of the Internet
comments: among the listed companies, Nan property (603506) qinchengli is the first commercial project of "light asset export management". Visionary (002841) has become the first hardware service provider of Alibaba new retail, jointly building the landing ecology of smart stores. Dashi intelligence (002421) has cooperation with ALI Alipay.
> Internet plus medical health policy will fall to the ground, and the demand for hospital information will rise
comment: electronic medical records, medical technology, information platform, grading treatment system, and big data analysis, cloud platforms and other high grade procts demand began to rise. Neusoft group (600718), Weining health (300253) and other listed companies have won relevant software projects in hospitals< More than 10 billion yuan of integrated circuit projects are contracted intensively, and consumables and equipment are the key points.
comments: there is a big gap between China and foreign advanced level in the field of semiconctor equipment and materials. With the proction of wafer factories, it is an inevitable trend to localize supporting semiconctor materials. We are optimistic about Jingrui (300655) and jianghuawei (603078), which are mainly engaged in wet electronic chemicals, And Shanghai Xinyang (300236) and other companies that have been invested by large funds<
05
policies and instries point to hot spots
Hainan explores and develops competitive sports lottery
mining Hainan lottery stocks: Aijian group (600643), Xinhualian (000620)
Hainan needs to implement big data strategy as a whole
Hainan big data concept stocks: aofei data (300738), gaoweida (300465)
Ali's first shopping center is about to open, Full integration of online and offline
Alibaba's new retail concept stocks: Nan property (603506), Shiyuan shares (002841), Dashi intelligent (002421)
- Alibaba is about to release its cloud communication procts
cloud communication concept stocks: Beiwei Technology (002148), mengwang group (002123), 263 (002467), etc Tianji Technology (300245)
panel manufacturers speed up the layout of 8K screen
8K screen concept stocks: precision electronics (300567), East China Technology (000727), BOE a (000725), shentianma a (000050)
indivial stock gold rush
> Huarui shares (300626) annual net profit increased by 44% year on year, and it is planned to transfer 10 shares to 8 shares and send 1 yuan< According to the information development (300469) annual report, it is planned to pay 1 yuan for 10 transfers and 8 transfers< The annual net profit of Shandong mining machinery (002526) increased by 567% year-on-year, and it is planned to turn 10 to 7< The annual net profit of Jianfa shares (600153) increased by 17%, and the holding of securities fund increased to 4.9% from 3.61% at the end of last three quarters
> Huayu automobile (600741) participated in the IPO of Yap automobile, and the company's shareholding accounted for 33.90% of the total share capital of Yap automobile before the IPO
> Tengda construction (600512) won the bid of 1.17 billion yuan civil construction project, accounting for 32.6% of the revenue in 2017
07
comments on leading stocks
Desheng technology-002908
comments: moreover, this vote resonates with the index in time sharing, which also belongs to the different to consistent seal back, so it is inevitable to enjoy the premium. The current objective disk situation, the strongest main line is undoubtedly Hainan, but not how to give opportunities. Digital China is an auxiliary line for diverting funds, which resonates with the index at the end of the day, but it is difficult to judge whether to take advantage of the situation or build up the momentum. It still depends on the situation.
It is a kind of optical fiber Ethernet interface card, which transmits signals according to Ethernet communication protocol. It is generally connected with optical fiber Ethernet switch through optical cable
eth0 and eth1 are used to distinguish network card names. They have the same meaning as windows local connection 1 and local connection 2
the subnet card here is not a practical network interface, but it can flash in the system as a collection interface, such as eth0:1, eth1:2
extended data:
linux operating system embeds TCP / IP protocol stack, and protocol software has routing and forwarding function. Routing and forwarding rely on the installation of multiple network cards in the host as routers
when a network card receives a degree packet, the system kernel will query the routing table according to the destination IP address of the degree packet, then send the degree packet to another network card according to the query result, and finally send the degree packet through the network card. The process of host is the core function of router
routing function is realized by modifying Linux kernel parameters. The sysctl command is used to configure and display kernel parameters in the / proc / sys directory
for security reasons, Linux kernel forbids packet routing and forwarding by default. In Linux system, there are two ways to enable forwarding function: temporary and permanent