wi-fi 'pre n'(?) devices on sale...

CNN.com - Confusion over next generation Wi-Fi - Jun 7, 2005

well, companies are at it already, and the specs haven't even been finalized (and prolly won't be for like a year).

the wi-fi alliance hasn't even ratified the new 802.11n standard, but already, scandalous companies are releasing 'pre n' and such products, very misleading and confusing.

i guess some of these products are probably very cool, but since the standard isn't out yet, i think it's immoral to try and leverage the hype (as well as the ignorance of consumers). just hafta see, i guess.

Frequency Hopping--it's a good thing

theres a good page explaining frequency hopping here.

the new dsl -- let me at it

Technology News: Internet: New DSL Standard Promises 10 Times the Speed

the itu approved the Very-high-bitrate Digital Subscriber Line 2 (vdsl2) and it looks like good stuff.

supporting up to something like 100 megabit/second downs. which is good. that'd be enough bandwidth for such buzzword services as video-on-demand (vod), prolly in high def, video conferencing, and lightning fast access for games and browsing.

hmm... 100 mbps, eh? wonder where they'll cap it at? you can find some good info about dsl here.

--theAdmin

markups, scripts, and interpretations...

work your 'net

so, i did the basic primer on html, or hypertext markup language. definitely doesn't explain everything about it, but it should've gotten you up and on your feet. 'sides, there's about a million tutorials (most of them decent) and reference sites out there. htmlgoodies used to be my favorite. haven't been perusing it lately, so i don't know if old joe burns is still keeping it fresh, but never fear--you won't have a problem finding good help when it comes to html.

now, from this point on (at least in this post), i'm going to assume you are at least sort of familiar with html. you know what a tag is. now, i'm going to take this a step farther.

markup languages, in the scheme of things are interpreted languages. there's a little debate on the matter as to what constitutes a real programming language. interpreted languages are interpreted by another program, and the translation, if you wanna call it that, is what's understood by the computer.

but, really, all programs are interpreted at some level. it's just a question of how, when, and where.

traditional programming languages like c, c++, basic, pascal, fortran, cobol, and all the other languages from the good old days.

java, on the other hand, is an interpreted language. you can run java on any computer that has a java virtual machine installed on it. the big advantage this gives is the ability to write one piece of software and have it run on everyone's computer with no changes.

of course, the downside is that you have to have a java vm (virtual machine) installed, and the vm has to be written for each type of computer that it is to be used on.

the vm is called a virtual machine because it acts like its own computer, but since it's all software (or virtual), there's no actual hardware involved. a virtual computer (machine).

but this is where people don't always see eye to eye. even traditional computer languages had to be interpreted. it's just that it was done by the programmer before the software was released.

a programmer writes a program (called coding) in basically just a plain text file. the file contains all the instructions (known as commands), written in a special way so that while a programmer can read them (most languages have syntax based on english), a special program called a compiler can read them as well. when you run a source code file through a compiler, it translates it into another language which the computer system can understand. we typically call the finished product an application or program, also known as an executable.

so, as you can see, both kinds of programs are interpreted or translated, just at different times. traditional programs are interpreted before the program is distributed, while interpreted languages translate it while the program is running.

the differences are self-evident for the most part. different approaches have different pros and cons.

now, you might be asking yourself what the heck all this has to do with html and networking and why you care. well, somewhere along the way, they came up with scripts and markup languages.

scripts are basically text files, again, and when they're executed, they are processed (or translated, again) into actual computer instructions. the advantage of scripts is that they are very easy to manipulate.

it's easy to open a script file on the fly, from more or less anywhere. now, they tend to not have quite as many features, but they are easy to learn, and easy to change and update.

scripts provide a way to provide more active, interactive, and dynamic functionality than html allows for on it's own. but scripts aren't just for web pages.

scripts can be used for many other purposes, including system tasks. remember batch (.bat) files (for all you DOS oldtimers out there)? scripts. just a text file with a string of commands written in it, and when the system reads, or parses it, each command is executed sequentially.

easy to change. no muss, no fuss, right? well, the major advantage compiled code has over interpreted code is speed. while it's true that they both have to be interpreted at some point, with traditional, compiled programs, all the number translation and interpretation has been taken care of by the time the end user gets ahold of a given piece of software. so, with compiled code, a user's computer reads it more or less directly, but an interpreted program has to get run through the vm every time.

easy to update, and good for distributing to multiple platforms (i.e. windows, osx, *nix, etc.), but it will never be as fast as something already compiled.

clear as mud?

well, the title of this is markups, scripts, and interpretations, so let me take a second to expand on markup languages (if you're still awake, that is).

by now, most of you are pretty familiar with html, or hypertext markup language. what makes html so special (and familiar) is hypertext. links. everybody likes to click on links, no? well, a lot of people forget that the rest of the acronym means something, too.

markup language.

a markup language is something that can be included into content (typically a document), which controls how the document behaves or is displayed. well, the style's caught on.

now, there's something called xml, or extensible markup language. the long and short of xml is that it is extensible or changeable. very modular.

you not only include tags, but you can basically describe what each of those tags are supposed to do, as well, which makes it tremendously more powerful (not to mention, tremendously more complex).

now, i'm not going to go into the breakdown of how xml actually works, as it's far beyond the scope of this post, but just keep your eyes peeled. one can already see many uses of xml popping up. VoiceXML (.vxml) is probably the most notable right now. i'll wager that many of you have already interacted with a voicexml script and not even realised it--you know those annoying interactive voice response computers which answer the phone at most companies, now? many of those are actually run by voicexml scripts (not dissimilar to a web page).

definitely cool, even though it sucks trying to get through to an operator, now.

anyway, maybe later i'll get together some good xml material and resources and work on a tutorial or something. 'til then, here's to big pipelines and open ports.

--theAdmin

found another good one here on blogsp0t

NetSec

just a quick sec to point out a good 'net security site on blogger. blogsp0t is great. if you're new to blogs, or haven't heard, go check it out.

--theAdmin

basic intro to html

we're going to take a little trip down memory lane for a little history lesson.

html (hypertext markup language) is the basic framework of the world wide web. so, what's a markup language, you ask? well, the simple answer is that it's in between a human language and a computer language. clear as mud?

okay, think of it this way...

the basic format of a web page is a page. so, it's a document. just like word files .doc, or rtf (rich text format), word perfect, etc. all of these document formats have one thing in common, and that's the ability to format text.

if you pick arial as a font, two markers are made behind the scenes--an opening marker and a closing marker. everything in between the two markers gets plastered in good old arial.

with html, the keyword is hypertext. so, what's hypertext, you ask? well, it's a link, or some text (or and image) that, when clicked, performs some action (like taking you to a new page).

with html, the whole page is just plain text. i'll say it again--html is just plain text with an extension of .htm or .html rather than .txt.

to make the page do what you want it to do, you simply insert these control codes, called tags, wherever you want them. a great example is the a tag, which is what makes a link.

so, if you write the word link into a web page and then look at it in a web browser, you'll see the word link. but if you wrap an a tag around it, like so...

<a href="http://cidviscous.blogspot.com">link</a>

and then reload the page, it will look like this...

link

pretty cool, huh? and it's not that hard. html tags are all enclosed in greater than and less than brackets. and if you look, you'll see the beginning tag, and then the actual word that's gonna be turned into the link, and then the closing tag (which is the same tag, preceded by a slash). everything in the middle (in our case, the word link) gets turned into a link.

that simple.

now, there are hundreds of other tags to do pretty much anything you wanna do. images, formatting controls, comments, font controls, tables, forms, whatever....

but how do they do all the cool things that html doesn't allow for, you ask? well, this is where it branches off into a few different vectors.

dhtml--dynamic html. dhtml never quite caught on in and of itself, but it basically offered some more advanced controls for laying out your pages and moving things around the page. it eventually gave way to css....

cascading style sheets (css) offer more advanced and flexible methods of formatting the page (controlling the way it looks). you can get absolute positioning (the ability to put an object in an exact location). the reason this is useful is that it gives the author the ability to control exactly where something will show up, regardless of the web browser or the screen resolution (within certain limitations)...

css takes a little bit to get used to, but you can definately get some very interesting results with it. but what happens when you push style sheets to their limit?

scripting!

so, what's a script? scripts are the next step closer to a real programming language. in fact, scripts are known as interpreted programming languages. but before i get too far ahead of myself i'm gonna stop. scripts need their own explanation and i'm going to take the time to do it right, so keep your eyes peeled. in the mean time, here's a few good links....

the w3c html intro
htmlgoodies
htmlbasix
w3c schools
davesite html tutorial
ncsa's beginners guide

keep exploring, everybody....

--theAdmin

some good links...

so, i've tossed a few ideas back and forth about which way to go with this, and after careful deliberation i've decided to simply provide links to some good tcp / ip info sites because there are already plenty of docs which do a better job of it than i ever could. so, without further adieu...

here's the rfc and a tcp/ip and the handbook. yale's got a pretty good introduction to tcp/ip located here. there's a good doc here that lays out tcp/ip's role in the internet's design and the model it creates. and the onecomputerguy has a great page laying out some basic troubleshooting tactics. also some good information here, here, and here. microsoft has some info about xp's implementation of tcp / ip.

the important thing to remember is that it's tcp over ip. that's what the slash means. and it also means that other protocols can be run over ip. voice over ip (voip) ring a bell? well, okay--voip's not really a protocol in and of itself, but there're a couple of flavours running around that prove my point. in order to connect to the internet, you have to have an ip (or internet protocol) address, but that's by no means the only thing out there...

anyway, more links...

http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/ip.htm
http://www.itprc.com/tcp_ip.htm
http://www.sangoma.com/fguide.htm
http://www.protocols.com/pbook/tcpip1.htm
http://www.cisco.com/warp/public/535/4.html
good basic tcp/ip faq
http://www.private.org.il/tcpip_rl.html
interesting tools and docs
http://www.warriorsofthe.net/
yale again
microsoft, again
yarl (yet another resource list)
http://www.faqs.org/rfcs/rfc793.html
http://www.ietf.org/rfc/rfc1180.txt
http://www.linuxjunkies.org/network/tcpip/introa.html
http://www.protocols.com/pbook/tcpip1.htm
http://www.cse.ohio-state.edu/~jain/refs/ipqs_ref.htm
an interesting idea
or just google for it.

there are about a million sources for this (and any other protocols you wanna learn about....) out there for the taking. and plenty of good stuff you can learn in school, too.

--theAdmin

the web

well, i guess we'll have a little session for all the newbies out there. take a second and explain how the web works. when the average person thinks about the internet, they're usually speaking about the world wide web. in reality, this is only a fractional part of the internet, but it's an easy mistake to make.

the web is huge, it's flamboyant and colourful, and it's very commercialized. there's actually a whole lot more to the internet than google and hotmail.

...but that's not what this article's about. we're gonna talk about the bright, animated, click-powered collage that is the world wide web.

the web makes things easy for people for several reasons. it's claim to fame is the easy point and click navigation that makes it such a breeze to move from page to page to page (and trust me, there's an endless supply of new stuff to look at).

all you need to experience this magical world of wonder (seriously, folks, you can find anything you want out there if you look hard enough...) is a program called a web browser and an internet connection.

the connection part could come in a variety of flavours--a modem and a phone line, a dsl modem (which also needs a phone line), a cable modem, a direct fiber connection, wi-fi, cellular or pcs card, or a host of other choices. like with anything, different options have both pros and cons.

and likewise, you've also got choices on the browser. firefox is my personal favourite. it's available, for free, and it's open source (which means you can see the code which makes it up, see how it works, and change it if you want) which is cool. another thing that makes firefox cool is the extensions platform. the developers created a way for other developers to make extensions (sort of like plug-ins) for pretty much anything you wanna do. very cool. and useful.

microsoft has their own browser, internet explorer, which comes bundled with windows. personally, i've never been a huge fan of ie, but it has a devoted following (not to mention a lion's share of the browser market...).

there are many other browsers out there--mozilla (what firefox is based on), lynx (a text only browser), opera, etc. different browsers offer different features, are open to different exploits, and have their own strengths and weaknesses just like anything else. pick the one that works for you.

now, obviously, if you are reading this, you've already had some experience with the web and web browsers in particular (even if you didn't realize it), because this is being published on the web, but many people don't think about these kinds of things and they should.

your browser is like your ride on the web. some have muscle, some have style. different strokes for different folks, but you wanna make sure that you get the most out of your time, right?

the other side of the coin--so, after a few clicks, it becomes clear how easy it is to get from place to place on the www (actually finding what you're looking for is a different matter) and how much stuff is actually out there. one of the main reasons it exploded like it did is the ease of creation.

html. it stands for hypertext markup language, and it makes the web go 'round. at one point in time, it was cake to learn (still pretty easy when compared against a traditional programming language...), it doesn't take much to get it going, and it's (at least in theory) a universal language.

the world wide web consortium is the organization which releases the standards which define html (which is the language of the web). they've also got a lot of documentation which can help you learn how the web works. another great site is html goodies.

now, for those of you who want to publish a web page and don't want to commit the time it takes to learning html, there are many programs that will do it for you. and oftentimes, you can find a free site which will not only host your page (actually make it publically available on the 'net...) also provide free or inexpensive tools for developing the site for you. blogger or geocities both provide (very different) services which fall into this category.

i'll get into more details about html (and other markup languages) in a later post, but just remember kids--the internet comprises much more than just the world wide web...

--theAdmin

net working -- networking -- network 'ing

how is your network switched???

...
google defines the word network like so. pretty simple as a basic concept. in fact, most of us take for granted how much of our enironment is networked.

stop and think about it. your phone, cell, car, music player, computer, pda, tv, maybe even your dvd player or fridge, are all networked these days. we often forget about this fact, or don't fully comprehend how pervasive this new paradigm is. our whole lives are being connected by networks, and little by little, we're forgetting how things work when they're not networked.

the simplest definition of a network is two or more objects or entities connected a such a manner as to allow communication or the sharing of resources. this doesn't necessarily have to involve computers. the pots (plain old telephone service) system is a network. the postal system is a network. your circle of friends is a network.

the method which the data and/or resources are conveyed or transmitted makes up the format, or protocol of the network. the hardware that actually connects the networked items can be referred to as the infrastructure.

okay, so, let's break this down just a little further. in the case of pots (the phone system), the protocol (at least on one level) is known as circuit switching. the pots system is a circuit switched network. the hardware, or infrastructure involved would be the wiring in your house or office, the bridge which connects your home's wiring to the phone company's wiring, the copper that runs to your local exchange, and so on and so forth.

now, on a bit of a side note, the public phone system is no longer circuit switched (and hasn't been for a long time) but the connection your phone makes to the exchange is still circuit switched. they now use what's called packet switching to actually route the calls around (it's how the internet works...) for efficiency's sake.

with circuit switching, an actual electrical circuit is formed between the point of origin (you) and the termination point (whoever you're talking to), which means it's not very efficient (because you have to have a dedicated physical connection all the way from the start to the end...) all the time.

so, somebody very much smarter than myself thought of the idea of packet switching. with a packet switched network, there is still a connection between you and whoever you're connected with, but it's not dedicated. in other words, it's not open all the time. the networking protocol (the method, remember?) basically chops up whatever you're sending into little chunks, called packets. now, this may seem kind of silly, at first, but there are certain distinct advantages you gain by utilizing packet switching. one of the most important (basically, the reason it was created) is that more than one connection can be made over the same pipeline.

confused, yet? okay, think about it this way--if you live in the boonies and have one neighbor next door, but only one phone line comes out that far, only one of you can be on the phone at a time (since it's circuit switched). whenever you're talking on the phone, the connection is being held open on your end. now, if that same line was set up to use packet switching, both of you could use the line at once. instead of the information flowing in a circuit, packets from your house and your neighbor's house can be alternated down the same line (much like red and blue cars using the same road). on the receiving end, the protocol takes all the particular packets that belong together and reassembles them in the correct order.

and the best part is, it all happens so fast, humans can't tell. it runs behind the scenes. a good example of how fast this process actually is, is your cell phone...

when you're talking on a cell phone, you perceive a constant stream of audio going from your phone to whoever you're talking to, and a corresponding stream coming from them to you. but actually, your phone takes samples of your voice (hundreds of samples every second) and sends these little chunks as packets. on the other end, they're put back together in the right order and it all happens so fast that to you, it sounds like a constant stream of voice. (a good analogy would be a film strip--lots of individual frames, run in order, fast enough, looks like a moving image to the human eye. this works the same way, but with audio... or anything else you like).

there are other benefits--one of the most useful of these benefits is error correction. using certain techniques, (all of which are beyond the scope of this post) the validity of each packet. if a bad one is detected, it's a simple matter to re-send the bunk packet rather than sending the whole thing again...

now, there are many forms a network can take, and many methods and hardware types which can be utilized to network devices. different methods have different stengths and weaknesses. certain techniques work better for some purposes and others work better for others. unless you're a nerdy von nerdberg, or a curious mind, most of that is more than you'll ever need to learn about. but, even if you never plan on setting up a network, or fixing a networking problem, or don't care what goes on behind the scenes, you should still get a basic understanding of what these networks actually do and some of the things of which they are capable.

we use various networks everyday of our lives (often without even thinking about it) and careless and ignorance are the two biggest ways to get into trouble. those who know, know, and those who don't fall victim. so pay attention.

hope this helped (or entertained) somebody out there. if you've got anything to say, please feel free.

--theAdmin

primero posta

so... this is it. first post. lemme just take a sec to explain the format of this site. it will be an overview of various networking methods and techniques (with applications on various levels ranging from the newest newbie to the more advanced and arcane corners of the computer and communications world...)

i will be posting tutorials and articles, links to many great resources, and lots of other fun stuff while we're at it. if you have any questions, comments, requests, corrections, etc. please feel free to post away.

the publisher (me) provide no warranty/guarantee. all information will be verified to the best of my abilities, but people are human (most of them, anyway...) and mistakes will be made (hopefully not very many of them...). if you find a mistake, or if you have something to add or expand on, please don't hesitate to post directly to this forum, or mail me the content directly. don't be shy. we're all in this together, and if you don't speak out when you see something that needs to be spoken about, who will? 'til then, my friends...

--theAdmin