I didn't think that such a question would interest me. However, this is what happened - I had Internet at home and the tariff was 6 megabits, but the speed did not rise above one megabit. Injustice? What to do? I got into the router settings and found, among other things, two interesting parameters Upstream SNR and Downstream SNR.

So what are Downstream SNR and UPstream SNR? At the beginning, a little necessary theory, and at the end, a smoothly flowing answer to this interesting question.

What is Downstream SNR and UPstream SNR?

ADSL (English Asymmetric Digital Subscriber Line - asymmetric digital subscriber line) is a modem technology that turns standard analog telephone lines into high-speed access lines.

ADSL technology is a variant of DSL, in which the available channel bandwidth is not symmetrically distributed between outgoing and incoming traffic - for most users, incoming traffic is much more significant than outgoing traffic, so providing more bandwidth for it is quite justified. Plain phone line uses a frequency band of 0 ... 4 kHz for voice transmission. In order not to interfere with the use of the telephone network for its intended purpose, in ADSL the lower limit of the frequency range is at the level of 26 kHz. The upper limit, based on the requirements for data transfer rates and the capabilities of the telephone cable, is 1.1 MHz. This bandwidth is divided into two parts - frequencies from 26 kHz to 138 kHz are assigned to the outgoing data stream, and frequencies from 138 kHz to 1.1 MHz - to the incoming one. The frequency band from 26 kHz to 1.1 MHz was not chosen by chance. Starting from 20kHz and above, attenuation is linear with frequency.

This frequency separation allows you to talk on the phone without interrupting data exchange on the same line. Of course, situations are possible when either the high-frequency signal of the ADSL modem negatively affects the electronics of a modern phone, or the phone, due to some features of its circuitry, introduces extraneous high-frequency noise into the line or greatly changes its frequency response in the region high frequencies; to combat this, a low-frequency filter (frequency splitter, English Splitter) is installed in the telephone network directly in the subscriber's apartment, which passes only the low-frequency component of the signal to ordinary telephones and eliminates the possible influence of telephones on the line. Such filters do not require additional power, so the voice channel remains in operation when the electrical network and in the event of a malfunction of the ADSL equipment.

Transmission to the subscriber is carried out at speeds from 1.5 to 6 Mbps, although today there are devices that transmit data at speeds up to 8 Mbps, but this speed is not defined in the standard. Service channel speed can vary from 15 to 640 KBit/sec. Moreover, each channel can be divided into several logical low-speed channels. Max speed line depends on a number of factors such as line length, cross-section and cable resistivity. Also significant contribution contributes to the reduction in speed by the fact that the ADSL line requires twisted pair(and not noodles) and shielded, and if it is a multi-pair cable, then in compliance with the direction and pitch of the lay.

DownStream SNR (downstream signal-to-noise ratio)
The higher this indicator, the better. If you have an indicator of 5-10dB, then this is not very good (most likely the "incoming" speed will be somewhere in the range of 2-4 megabits / sec high speeds You are most likely not to be seen. If you have an indicator of 15-20 dB, then this means that the signal level will allow you to work at 4-8 megabits / sec for signal reception (for the Internet, where the downstream stream significantly exceeds the incoming one, this is especially important). Well, values ​​​​of more than 20 dB are already a sign of "good, guaranteed quality" for the line. The higher the indicator, the faster the line you have.

Similarly for UPstream SNR, only for the stream outgoing from the client.

Outcome:

My indicators were around 10. Deciding that this was a mess, I decided to switch to another line that was connected to the apartment and lo and behold: the indicators became about 30 :) The problem with the Internet was thus solved.

Downstream sector in Russian economy has significant potential. IN Lately Great progress in the oil refining industry has been shown by companies united in the New Stream group for more than ten years. Downstream in the oil industry Russia is headed by Dmitry Mazurov. In addition to oil refining, the group works in the field of consulting and investment management. Its main asset is the Antipinsky Oil Refinery

A notable figure in the recent Vienna November conference " Project management to the downstream in the CIS and Eastern Europe" was Chief Engineer factory Sergey Murzin.

During the third annual conference, leaders and managers working in the downstream discussed the development of the industry. Design institutes were also represented.

Discussed innovative ideas in construction and technological developments. A fruitful discussion took place regarding the implementation of projects and the threat of their non-realization.

During the conference, convened round tables on various issues. A report by Sergei Murzin was heard on establishing contacts with foreign companies, in particular, oil product suppliers and subcontractors. He outlined the main principles of working with them.

Sergey Murzin informed about the plant's plans for the next few years. The prospects are quite good, since the enterprise, which processes 400 thousand tons of oil annually, has reached a capacity of 9 million in 10 years. In the spring, it is planned to launch a plant for the production of high-octane gasoline (Euro-5 standard).

A useful measure was the organization of excursions to leading European enterprises located near Vienna. Among them, OMV Schwechat Refinery and Borealis stand out. These enterprises comply with industrial and environmental safety standards. For ordinary citizens, information about the availability of the Green Phone service in Austria may be useful. Around the clock, any resident living close to the plants can request information on the environmental situation at the enterprise by phone. And the fact that there is an ecological reception at the Antipinsky plant is not known to everyone. Given the implementation social projects, Novy Stream has significant prospects for long-term development.

5 responses

In terms of source control, you " downstream" when copying (cloning, checking out, etc.) from the repository. The information was passed downstream to you.

When you make changes, you usually want to submit them" upstream" to get them into this repository, so that everyone pulling from the same source works with all the same changes. This is basically a social issue of how everyone can coordinate their work, not technical requirements source control. You want to make your changes to the main project so you don't have to keep track of diverging lines of development.

Sometimes you'll read about package or release managers (people, not tools) talking about making changes "upstream". This usually means that they had to correct the original sources so they could build a package for their system. They don't want to keep making these changes, so if they post "upstream" to the original source, they won't have to deal with the same issue in the next version.

One of the important aspects of git is that it is distributed, and its distribution pretty much means that there is no inherent "upstream" or "downstream" in the system.

It's simple means that there is no absolute reverse or reverse repo.
These concepts are always relative between two repositories and depend on how data is transferred:

If "yourRepo" declared "otherRepo" to be deleted, then:

• You pull out of"another" repo upstream("OtherRepo" means "upstream from you" and you " for another repro on descending").
• you push upstream("otherRepo" is still the "upstream" where the information is now being returned).

Notice the "from" and "to": you're not just "downstream", you're "downstream from/to", hence the relative aspect.

The gist of DVCS (Distributed Version Control System) is this: you have no idea what the downstream really is, other than your own repo relative to the remote repos you declared.

• You know what's upstream (the repo you're pulling or pushing from)
• You don't know what the downstream is made of (other repos pull or pull to your repo).

Basically:

In terms of "data flow", your repo is at the bottom of the ("downstream") flow, going out of repositories upstream ("pull from") and back to (same or different) repositories upstream ("push up"). ")).

You can see an illustration on the git-rebase git-rebase page with the paragraph "RESTORING FROM UPSBREAM REBASE":

This means that you pull the "upstream" repo where the rebase happened and you (the "downstream" repo) are stuck with the consequence (lots of duplicate commits because the branch rebased upstream has recreated the same branch's commits locally).

This is bad, because for a single "upstream" repo, there might be many downstream repos (i.e. repos pulling from an upstream rebase repo), all of which have the potential to deal with duplicate commits.

Again, similar to "data flow", in DVCS one bad "upstream" command can have a "ripple effect" downstream.

Many git porcelainish commands accept a mixture of flags (i.e. options that start with a dash "-") and options intended for the basic git rev-list command they use internally, and flags and options for other commands they use after git rev-list, This command is used to distinguish between them.

Term upstream also has an unambiguous meaning as it is part of the GIT toolkit, especially regarding tracking

For example:

$git rev-list --count --left-right "@(upstream)"...HEAD >4 12

will print (last cached value) the number of commits behind (left) and ahead (right) of your current working branch compared to ( if there is) is currently the tracking remote branch for this local branch. Otherwise, it will display an error message:

>error: No upstream branch found for ""

• As already mentioned, you can have any number of remotes remote control for a single local repository, for example, if you checkout a repository from github and then issue a pull request, you probably have at least two: origin (your forked github repo) and upstream (the github repo you forked from). They are just interchangeable names, only the URL "git@..." identifies them.

Your .git/config reads:

fetch = +refs/heads/*:refs/remotes/origin/* url = :myusername/reponame.git fetch = +refs/heads/*:refs/remotes/upstream/* url = :authorname/reponame.git

• On the other hand, the value @(upstream) for GIT is unique:

It is the "branch" (if any) at the "specified remote" that is tracking the "current branch" in your "local repository".

This is the branch you fetch/pull when you issue a simple git fetch / git pull with no arguments.

Let's say you want the origin/branch of the remote branch to be the tracking branch for the local master branch you checked out. Just issue:

$ git branch --set-upstream master origin/master > Branch master set up to track remote branch master from origin.

This adds 2 options to .git/config:

Remote = origin merge = refs/heads/master

try it now (assuming the "upstream" remote has a "dev" branch)

$ git branch --set-upstream master upstream/dev > Branch master set up to track remote branch dev from upstream.

Git/config now reads:

remote=upstream merge=refs/heads/dev -u --set-upstream

For each branch that is updated or successfully pushed, add a link upstream (tracking), used without git -pull (1) arguments, and other commands. For getting additional information see branch. .merge in git-config(1).

branch. .merge

Defines with branch. .remote branch upstream for this thread. It tells git fetch/git pull/git rebase which branch is being merged and can also affect GIT push (see push.default). \ (...)

branch. .remote

When in branches , it tells git fetch and GIT to push which remote fetch from /push to. The source is used by default if the remote is not configured. origin is also used if you are not in any industry.

Upstream and Push (Gotcha)

git config --global push.default upstream git config --global push.default tracking (deprecated)

This prevents you from accidentally pushing branches that you are not ready to push yet.

This is a bit of informal terminology.

As far as Git goes, every other repository is just a remote one.

Generally speaking, upstream is where you cloned (origin). Downstream is any project that integrates your work with other works.

The terms are not limited to Git repositories.

For example, Ubuntu is a derivative of Debian, so Debian is upstream for Ubuntu.

There is, alas, another use of "upstream" that the other answers here don't fall into, namely to refer to relationships between parents and children within a repo. Scott Chacon in the Pro Git book is particularly prone to this, and the results are unfortunate. Do not imitate this way of speaking.

For example, he talks about merging, which leads to fast-forward, that this happens because

the commit your branch points to was directly upstream from youre on

He wants to say that commit B is the only child of the only child of ... the only child of commit A, so to merge B into it is enough to move ref A to point to commit B. Why should this direction be called "upstream" rather than "downstream", or why the geometry of such a pure line graph should be described "immediately upstream" is entirely unclear and probably arbitrary. (The man page for git-merge does much best work on explaining these relationships when it says "the branch's current branch is an ancestor of the named commit". This is what Chacon should have said.)

Indeed, Chacon himself seems to use "downstream" later to mean the same thing when he talks about rewriting all child commits of a remote commit:

You must rewrite all commits downstream from 6df76 to completely remove this file from Git history

Basically, he doesn't seem to have a clear idea of ​​what he means by "upstream" and "downstream" when referring to the history of commits over time. Thus, this usage is informal and discouraged as it is just confusing.

It is quite clear that every accomplishment (except one) has at least one parent, and that the parents' parents are thus ancestors; and in the other direction - children and descendants. This is the accepted terminology and unambiguously describes the trend of the graph, so it's a way to say when you want to describe how commits are related to each other in the geometry of the repo graph. Don't use "upstream" or "downstream" in this situation.

[Additional note: I was thinking about the connection between Chacon's first sentence I quote above and the git-merge man page, and it occurs to me that the former may be based on a misunderstanding of the latter. The manpage describes a situation where the use of "upstream" is legal: expedited forwarding often happens when "you're tracking an upstream repository, you're not committing local changes and now you want to update to the new upstream". So maybe Chacon used "upstream" because he saw it here in the man page. But there is a remote repository in the man page; there is no remote repository in Chacon given the example fast forwarding, just a few locally created branches.]

According to the IEA, global demand for petroleum products could rise by about 6.1 million barrels per day through 2022. New requirements imposed by the International Maritime Organization from 2020 on marine fuels could lead to a widespread increase in prices for petroleum products. Wood Mackenzie argues that shipping companies' fuel costs could rise by more than 50%, to $174 billion a year. There are also estimates of an 85% increase in fuel costs. But in addition to the impact on shipowners, these changes may have a cumulative effect and affect freight rates, automobile and jet fuel prices.

The management of Vitol, the world's largest oil and petroleum products trader, believes this will "turn the market" as banned high-sulphur marine fuel (4% of global oil demand) is an important part of many refineries' refining processes. Experts suggest that prices for petroleum products (marine fuel, diesel fuel, gasoline and jet fuel) may rise by $10-20 per barrel. The increase in tariffs for shipping will lead to an increase in the cost of oil supplies to refineries. Many refineries will not be able to withstand such changes. European oil refineries will find themselves in a difficult position. Credit Suisse predicts the imminent closure of several refineries in France, including due to the decision of the International Maritime Organization. This will be facilitated by the recent decision of the French authorities to ban the sale of cars with gasoline and diesel engines in the country from 2040, as well as to consistently stimulate the sale of electric vehicles by the state.

© RIA Novosti, Mikhail Klimentyev

Rosneft became the most expensive Russian company in terms of capitalization, the value of its shares increased by 60% last year. Thanks to a consistent strategy, pursued for more than fifteen years, of absorbing numerous assets in Russia and abroad, or “vacuum cleaner”, as Putin calls it, VIOC production reached a record 265 million toe last year. e.

In July, the company became the winner of the auction for the development of the Erginsky field in the Khanty-Mansiysk autonomous region, the last major asset from the unallocated fund with reserves of 65.777 million tons. A good replenishment of the portfolio - about half of what Rosneft managed to add last year.

Thus, according to DeGolyer & MacNaughton, the proven hydrocarbon reserves of VIOC, taking into account the assets of the absorbed Bashneft, amounted to 37.772 billion barrels. n. e. (5.111 billion toe). During the year, the reserves of VIOCs increased by 3% or 131 mmtoe. e. The company's share in Russian oil production is about 40%, and in world production 6%. A separate story is the gas projects of Rosneft. The company's gas production in 2016 amounted to 67.1 billion cubic meters. m, which is 7.3% higher than the previous year. VINK overtook NOVATEK and became the leader among Russian independent gas producers.

The company claims that the average unit cost of producing hydrocarbons is currently $2.5/boe. e., although a number of Russian experts question this figure. We can note a significant increase in drilling at Rosneft: despite the poor price environment in 2016, the volume of development drilling increased last year by 35% compared to 2015, and the number of new wells amounted to 2.6 thousand units. The company took the path of developing its own service: last year, the takeover of Targin allowed it to reach the share of internal service in drilling at the level of 60%.

Let's take a look at one of the world leaders oil industry ExxonMobil. Its capitalization is now $420 billion, while LUKoil's capitalization is $70 billion, which is six times cheaper. At the same time, the oil reserves of the American company are estimated at 3.12 billion tons, and LUKoil - at 2.8 billion tons, which is quite comparable. Lukoil produces only half as much oil as Exxon.

The same analogy can be drawn with other Russian and Western companies, as a result of which we really see the underestimation domestic enterprises. What is the reason and how do foreign firms earn more money (and, accordingly, are more expensive on the exchanges)?

Compare with compare

The value of an oil company lies not only in the amount of oil reserves in the fields, but also in the ability to turn these reserves into profit for shareholders. The greater the profit stream, the better and the more expensive the company. And the profit consists of two components: from the extraction and sale of crude oil and from the processing of oil into other products with their subsequent sale.

First, let's look at chart 1 the ratio of production and processing (coefficient Ksp) at oil enterprises. It can be seen here that VIOCs (vertically integrated companies) process about half of the oil they produce themselves. And at this time, ExxonMobil has this ratio of about 200%, that is, the company refines three times more oil than it produces itself: in fact, ExxonMobil refines oil, for example, from LUKoil, receiving additional income for each processed ton, and quite a lot .

Note that in the structure financial results ExxonMobil's 2007 upstream* segment accounted for only 65% ​​of its net income, with about a quarter coming from the downstream** segment and more than 10% from chemical production.

As can be seen from the diagrams, both the average selling price of products and the ratio of net profit to production at ExxonMobil are three to four times higher than those of Lukoil and Rosneft. These are treasured figures that characterize the insufficient operational development of Russian VIOCs and explain the corresponding lag in market capitalization. So it's time to talk about the local overvaluation of the Russian oil industry. By the way, the depth of the collapse in the value of shares on the stock exchange on July 25 of this year indirectly confirms this.

Downstream - the basis of intensive growth

Almost all companies are valued on the market at an amount slightly higher than their revenue. This is characterized by the so-called P/S ratio (capitalization / revenue). When an enterprise is actively growing and investors believe in its bright future, the ratio can be 1.3 or higher. When a company stagnates or a crisis of investor confidence approaches, the ratio drops to, for example, 0.9. Thus, the growth of revenue in any case has a positive effect on the capitalization of the company: an increase in revenue by 1 rub. on average causes an increase in capitalization by 0.9–1.3 rubles. From this it is clear: in order for shares to rise in price, as mentioned above, it is necessary to sell more and at a higher price. For an oil company, this means the following:

• produce more oil and count on the growth of its cost;
• extract more oil and produce more expensive products from it (refining);
• to additionally buy foreign oil on the side and process it together with their own, creating additional surplus value.

It can be seen that these options are arranged in ascending order from the extensive path of business development to the intensive one. Moreover, processing can and should be understood as the production of not only gasoline, fuel oil and diesel, but also basic monomers for organic synthesis, as well as polymer products and products from it. At each stage in this chain, an additional increase to the final selling price will be created, which means that the company's total revenue will increase. This is not only a guarantee of increasing capitalization, but also a factor in a significant increase in the stability of the business as a whole, as the business diversifies. Both are very positive for investors' perception of the stock.

Probably, many have already noted that in the above ladder, Russian vertically integrated oil companies are on the first or, at best, on the second step, since they are not yet able to process even 60% of their own oil. At the same time, leading foreign analogues are actively positioned just at the third stage, producing highly processed products from their own and foreign oil. This is what provides additional sales volumes both in kind and in monetary terms, allowing foreign companies have a much higher average selling price of products and, accordingly, receive much more revenue with comparable or even lower oil production volumes compared to Russian VIOCs.

Refinery and cyclical risk

It would seem that everything is clear: actively build refineries and reap the benefits in the form of growth in financial results and quotations own shares! but Russian companies until they do so. Why?

The construction of an oil refinery is a lengthy and very costly process. To build a plant capable of processing oil into high-quality fuel (Euro-4/5) at a modern level, it is necessary to invest about $350-400 per ton of processing, that is, a plant with a capacity of 6 million tons per year will cost $2.1-2.4 billion. For comparison: now LUKoil owns the third largest oil refinery, Volgogradneftepererabotka, with a capacity of about 9.5 million tons.

The creation of the production of polyethylene or polypropylene already requires many times large investments. The payback period for these projects lies in the horizon of six to seven years or more. With such a period, risks of both a financial, economic and political nature increase. Nobody wants to take risks just like that. Moreover, the oil products market is cyclical and periods of high profitability (like now in Russia and like five years ago in the US) are replaced by periods of zero and even negative (like in the US now and 25 years ago). In an era of high oil prices, refinery costs rise, profits decline due to falling consumer demand.

Where is the guarantee that, having invested billions in the construction of the plant, the company will not face the fact that in six or seven years the income from processing will fall to the minimum level and the payback will be forgotten for a long time? There are such examples. At one time, large American VIOCs considered processing as something secondary and not corresponding to the main business either in terms of the scale of activity or in terms of profitability. It was in the distant 1980s, and then the management of VIOCs seriously raised the issue of withdrawing refineries from the structure of oil holdings. At this time, as if foreseeing the future and taking advantage of the very low prices for oil refining assets, Valero Energy bought a large number of refineries. When refining profitability began to rise due to falling oil prices, it made huge profits, becoming one of the leading players in this market. Now the economic cycle in the industry has returned to the same point where it was in the early 1980s, and times have come for recycling in the States. This segment within VIOC shows zero profitability or even a loss. It is not for nothing that LUKoil, which bought the ConocoPhillips gas station network in the US a long time ago, began selling them partially this year - profitability has fallen, and interest in the asset has also decreased.

In Europe, the situation is better, while in Russia it is still relatively far from such a crisis. Thus, the good news is that economic cycles in oil refining do not coincide in phase from region to region: somewhere there is a decline, but somewhere at this time there is an increase. That is why domestic vertically integrated oil companies are modernizing factories in the Russian Federation, and in Europe they are already buying finished assets- there is a more understandable tax regime, a solvent client and the highest fuel prices. However, many refineries in Europe cannot be bought. The same "Lukoil" was able to acquire a stake in the Sicilian enterprise after many years of failures, when the assets were literally pulled out of his hands. Sometimes, it seems, for purely political reasons. So it was in Holland, the Baltic States, Poland. Even in Serbia, the purchase by Gazprom Neft of control in national company NIS meets fierce resistance. Therefore, large-scale expansion to Europe for Russian firms practically unrealistic. To significantly increase the volume of processing, it is necessary to build enterprises here and now. And not only in the European part, but also in Western Siberia and Far East. This, in addition to reducing transportation costs, will allow us to target different markets with different demand dynamics and cycle phases.

The state is the best guarantor

So, there is a danger of unfavorable development of the macroeconomic situation. It can be smoothed out, but it cannot be completely eliminated. Let's add here the absence of a tax policy stimulating deep processing: after all, at present there are quite high export duties on deep processing oil products and considerable import duties on the import of unique equipment. All this forms not the best background for the development of the downstream segment.

And this is where government support is needed. There is a need for tax incentives that can make deep processing so profitable business so that VIOCs go to the independent construction of refineries. Tax incentives should be directly proportional to the depth and share of own processing in the operating structure of the company, and they can be extended to other business segments. And this is logical when it is necessary to create conditions for accelerated development: since you produce extra-pure gasoline and a scarce polymer, get additional benefits from the production tax. Fair? Quite! Since you are not driving cheap oil abroad, but making it a valuable product here, on the spot, developing the economy and creating new jobs, it means that you use Russian mineral resources more efficiently than others and have the right to additional preferences.

At present, a turn towards precisely such an attitude in the highest power structures is gradually being outlined. If this position prevails, companies will be much more active in creating added value and developing the high-tech processing segment of their business. Then it will be possible to compare Lukoil and ExxonMobil directly, they will have similar operating structures and similar income structures. So far, these are internally different companies.

Investment Conclusion

So, we can say that the analysis carried out shows: Russian vertically integrated oil companies are in fact not yet vertically integrated enough. Accordingly, it is not necessary to wait for a rapid growth in quotations before this operational imperfection is eliminated. The only drivers of growth remain world oil prices and tax changes associated with a reduction in the MET rate and a revision of the system for calculating export duties on oil and petroleum products, which will allow companies to keep more operating profit than is currently possible.

* Upstream - mining

** Downstream - processing and marketing