In other types of computers, the terms boot monitor , boot loader , and boot ROM are used instead. The BIOS boot process Edit When the x86 processor is reset, it loads its program counter with a fixed address near the top of the 1 megabyte real-mode address space. A jump instruction then directs the processor to start executing code in the BIOS. If the system has just been powered up or the reset button was pressed "cold boot" , the full power-on self-test POST is run. This saves the time otherwise used to detect and test all memory.

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The use of the PXE specification is free not requiring fees or royalties of any kind. Include references to related predecessor technologies only when they are intimately linked to PXE and the net booting process itself. Include references to related parallel technologies only when they belong to the same equivalence class i. Link to representative PXE projects only when supported by independent sources proving the linked project relevance and quality.

Thank you. What do you think? Thanks, Drmies talk , 16 December UTC no problem on my side, but you please stick around and see how the thing develops Therefore, considering to release the semi-protection sounds like a very weird idea to me.

Before we can trust this IP again, he should learn to write and edit articles on a few other topics, for example by writing an article on SERVA or even better articles on topics totally unrelated to PXE. The main issue of the article in its present form is that it leaves a lot to be desired in explaining PXE as is. So, we should think about adding a lot of contents rather than to delete some. If the IP wants to discuss PXE at a more detailed level, he can present his content drafts on this talk page, and if they are fine, other editors will incorporate them into the live article.

The presented guidelines are tailored to talk about PXE and they pretend to clearly set the boundaries for doing so. Yes; some stuff like the mention of the warez based project ERPXE and the like has to be gone, but the guidelines also i. So much effort went into so little new content. Why would mentioning open-source implementations be considered a bad thing?

If you see the references, links, and the overall spirit of the article everything seems to revolve around a project that being in fact a "derivative" of PXE so far has not ever produced a single official specification document. We pretend to talk about the "standardized" PXE protocol here; and this is said at the first point of the guidelines draft. I think it is important setting the boundaries of what should be discussed here and what is better discussed somewhere else. BTW I have undone your inclusion "or open-source PXE implementations" from the 1st guideline as it is in fact contradictory with the spirit of discussing only the PXE specification here and no particular derivative projects no matter if they are open-source or not.

Probably next time instead of directly editing the guidelines draft it would be a better idea discussing here the proposed change first in order to avoid other inconveniences. And why are you hiding behind an IP address all the time? About adding references myself well the article is still locked; hopefully that is going to be fixed soon.

Also let me tell you that the references section is something that should come after getting done the article core; and that that core should be made out of explaining as simple as we can the PXE standard.

Could you also, please, provide a quote from the article, where that "false idea" is actually transmitted? I have added the word non-standard in order to diminish a bit the distortive effect of that sentence.

Should we add a link to iPXE there, as an example? That brief summary should be useful to readers, letting them know what key additional benefits are there to be offered by those open source PXE boot images — if you agree. I really do not think we have to mention the not applicable negative concept of proprietary implementations nor having an almost spam link to iPXE claiming to have more features in a point of the article where the PXE protocol has not been even described yet.

BSDP is the protocol that should be quoted here instead if we follow guideline 3. It was already there , before my first edit performed on this article. Once again, could you please explain why are you refusing to create a Wikipedia account, what would allow you to edit this article?

For many people this represents a serious security risk; an attacker could trigger the booting of malicious code located anywhere in Internet just using this iPXE extra "feature", all of this in a moment of maximum vulnerability as a booting target never has a working anti-virus layer. I could also mention additional drawbacks like i. Drmies has said he was willing to unlock the article and has agreed then I think it is just a matter of time for him being around and fixing the thing. Back at the time — for example — I used TFTP for booting some Cisco equipment in quite complex network layouts, and it all worked very well.

Also, I strongly disagree that big names are required for stability and compatibility of a software product. While it was semi-protected, you needed to become WP:Autoconfirmed , what boils down to having ten edits in total. UDP traffic is not as simple to track Required by NAT and is sensitive to inverse order arrival; while this is pretty common in Internet scenarios sure you have not experienced these problems in your "intranet" network layouts.

It is curious how this TFTP protocol "drawback" ends up "somehow" being a security feature. If you are a big "bank" migrating to i. Windows 7 and you are planning to do that using your network then sure you will not be interested in iPXE; did I hear why?

Also your comparison with DNS is not applicable when considering packet order inversion produced by alternative routing paths, remember a TFTP stream could involve hundreds of MB plus the protocol recovery features do not prevent errors occurring again and again and eventually reaching a transfer abort condition after a of retries.

A requesting host chooses its source TID as described above, and sends its initial request to the known TID 69 decimal octal on the serving host. Just as you said, in case of large amounts of data, retransmits handled within TFTP can pile up, resulting in such transfers being aborted. But then again, surfing the web would probably remain enabled, with some "L7 filtering" in place or whatever. On the other side, there are some other environments, where an open-source PXE implementation would be much more welcome than a closed one.

Those are the environments preferring to have the source code available, so it can be audited, verified for correctness, checked against backdoors etc. Internet transfers on the other hand are virtually impossible "but" from a TFTP point of view they are neither needed or "wanted". No way; thanks. Can you imagine a situation where some company might require the source of every piece of firmware a PC has?

I cannot. It all depends on the company, its size and its needs. In my opinion, having open-source implementations can only be a good thing. Also, many people would just love to get their hands on source codes of current SSDs firmwares. Those are just a few examples. It all depends of what a company or group of people need, or want. Why would anyone in the world go and write another encyclopedia? But I also understand your point of view considering the examples you just gave.

I also agree PXE is not the best example for that need. Go figure. Those codebases primarily for BIOSes are totally ancient, quite buggy, and prone to various security issues. Who knows what else is hiding within those binary blobs, and what knowledge is circling in blackhat communities? On the other hand, I agree that pragmatism is also very important It would be completely unreasonable to expect from an IT department of some bank to spend their time hacking iPXE or doing something similar; their primary job is to keep the printers running, with enough toner, and jam-free.

Just checking, are we going to continue our work on improving this article? You have to work with others. I will look into the protection issue. You can either further this discussion and thus the article, or stay out: baseless accusations are unhelpful.

So please stop harping on that point and address the substance of what the IP editor is saying. Thank you Ent. NE Ent agrees that protection should be done at the "lowest possible level", which I take to mean unprotection--Ent did not indicate that they think allowing IP edits is a problem, nor did anyone else.

Good luck, Drmies talk , 22 December UTC Please pardon me, but my focus was all the time on improving the article, and discussing that with Proof of concept;.


Talk:Preboot Execution Environment

The BIOS function is to bootstrap the hardware and optionally test functionality prior to an operating system being launched. The generic function with implementation specific entries is what this topic should cover. The Synopsis should not contradict that information. As for systems having code in permanent memory to cause the system to boot from external storage, sure, that has been how computers worked since and I assume a decade before that. And note that as I said, the main purpose of the BIOS is not to perform and initial program load, it is to provide functions for use after the system has initiated. It was only that, a collection of subroutines to provide "hardware abstraction" before that term was widely used. A self test function may also have existed.



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