User experience on 5G NR networks, expected under real conditions

 3r3197. 3r3-31. User experience on 5G NR networks, expected under real conditions
3r3184.  3r3197. 3r3184.  3r3197. 3r3178. Test download speeds on 5G NR networks in the range up to 6 GHz in Tokyo
3r3184.  3r3197. The 5G NR SA macro network segment model in Tokyo included 20 new 5G NR base stations, which were located on the same sites as the existing LTE cells. The 5G NR network model in Tokyo operated in the 100 MHz band at 3.5 GHz and the Gigabit LTE TDD core network in three LTE spectrum bands (3 × 20 MHz) (in Figure 1). The distribution between base stations and devices was modeled on the basis of high-resolution 3D maps of Tokyo, taking into account possible losses ...
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Phase antenna center (FCA) and its search in Ansys HFSS

Phase antenna center (FCA) and its search in Ansys HFSSWhen calculating the high-frequency technique with the use of mirror reflecting systems (parabolic mirrors), there is always the problem of searching for the phase center of the antenna (FCA), since proper operation of the mirror is possible only if the focus is on an antenna (called the feed, feeder, feedhorn) which has a phase wave front in the form of a sphere, and the center of this sphere is in the focus of the mirror. With any deviations, both the shape of the phase front from the sphere, and the displacement of the FCA from the focus of the mirror - the efficiency of the mirror system falls...
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Russian telecom operators have begun testing NB-IoT SIM cards for the Internet of things

Russian telecom operators have begun testing NB-IoT SIM cards for the Internet of things Recently it became known that Russian telecom operators began testing SIM cards for the NB-IoT communications standard. It is designed for the Internet of things, so that such SIM cards can be used together with the corresponding devices. According to market participants, the communication standard will become especially popular after the legalization of technology 3r-35c. eSIM
That will allow to abandon the SIM cards of the usual sample. 3r3365.  3r376. 3r3365.  3r376. Kommersant reports that MTS has released a new standard SIM card in a pilot project...
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Losses in mismatched line

In the literature described approximate formulas for calculating additional heat losses in uncoordinated transmission lines (cables, waveguides) due to standing waves. The limitation of such formulas is that the own losses of the matched cable should be up to 2 dB. Today, high-loss cables are increasingly used for microwave frequencies above 1 GHz. Broadband antennas often have a CWS 1. To find a compromise between the length of the line (for example, the antenna's suspension height), its cost, to estimate losses in a deliberately mismatched line (for example, 75 Ohm cable in 50 Ohm systems)...
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The Ministry of Communications proposed to switch to SIM cards with encryption from the FSB

The Ministry of Communications proposed to switch to SIM cards with encryption from the FSB
 
 
In order to implement the provisions of the "Yarovoi Law", the Ministry of Communications proposed to introduce on the communication networks Russian cryptographic protection systems, which will require the transition to new SIM cards. The draft order was published on the official portal of draft normative legal acts.
 
 
You can see it
by reference
.
 
 
Based on the data from the project map, the following is provided as a justification:
 
"The need to prepare a draft regulatory legal act is conditioned by the requirements for ensuring the integrity, stability and security of the unified telecommunications ...
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5G can replace cables - but not everywhere

Analysts from Citi have suggested (3r3r3? PDF
) That the 5G technology in the future can drive the cable Internet providers out of the market. Let's talk about how real this "threat" is: where the networks of the new generation will be able to replace the cables, and where - before this is still far away.
 
 
5G can replace cables - but not everywhere

 
/Flickr / kahunapulej / CC
 
 

Where 5G can replace cables


 
In the large cities

 
With a high probability of 5G ...[/h][/h]
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Seamless Wi-Fi-roaming: theory in practice

We deal with the technologies of roaming (Handover, Band steering, IEEE ???k, r, v) and conduct a couple of visual experiments demonstrating their work in practice.
 
 
Seamless Wi-Fi-roaming: theory in practice  
switch , to which both access points participating in the experiment are connected. Frames from one access point fell into one network card of the traffic collection system, the frames from the second to the second one. In the received dumps, only voice traffic was selected. The delay in switching can be considered as the time interval elapsed from the moment of traffic loss through one network interface, and before it appears on ...
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Decentralized messenger and a new generation telephone network

Decentralized messenger and a new generation telephone network  
 
Every time an article appears about a new messenger, most of the users of Habr in the comments are interested in - a centralized or decentralized IM?
 
If not, then - "everyone, guys, disagree".
 
Many, for example, also mention the decentralization of Skype, meaning what it was before 2011.
 
Let's then consider, as a liner and entry to the main idea of ​​the article, how Skype was in its golden years, before buying Microsoft.
 
 
(M1 Messenger) , which, on the one hand, is a decentralized messenger, and on the other hand can be defined as a next-generation telephone network.
 
 
In this platform...
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Networks for the most mothers. Part of the fifteenth. QoS

Networks for the most mothers. Part of the fifteenth. QoSSSSM-15. About QoS.
 
Now with the option Pull Request'ov .
 
 
And now we have reached the topic of QoS.
 
Do you know why just now and why this will be the closing article of the entire course of the SDSM? Because QoS is extraordinarily complex. The most difficult thing that was before in the cycle.
 
This is not some magical archiver, which deftly squeezes traffic on the fly and shuffles your gigabit into a hundred-gigabit uplink. QoS is about how to sacrifice something unnecessary, cramming the unintended into the framework of what is allowed.
 
QoS is so entangled in the aura of shamanism ...
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How SSH appeared on port 22

How SSH appeared on port 22 SSH by default it works on port 22. This is not a match. Here's the story of how he got this port.
 
 
When I ( Tatu Ilonen ) First published this story in April 201? it became viral: it was read by about ??? readers in three days.
 
 

The history of receiving port 22 for SSH


 
I wrote the first version of SSH (Secure Shell) in the spring of 1995. At that time, widely used Telnet and FTP .
 
 
But I still developed SSH for the replacement and telnet (port 23) and ftp (port 21). Port 22 was free and conveniently located between ...[/h]
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