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Firewall

I just got my first wireless-enabled laptop and I'm concerned about security. I've always used a hardware firewall at home but I'm going to college in a few weeks and though I'm fairly confident that the campus is pretty secure from the outside, I'm concerned about intra-network security.

I refuse to pollute my memory and complicate life by using a software firewall.

Firstly, is there any particular danger in wireless networking without a firewall? Can an ad-hoc network be established to me without my knowledge (as a type of attack, not as a feature).

And secondly, is a firewall really necessary? Although I'm very "good with computers" - I'm a computer science major - I have very little experience with network security. What will a firewall do for me, technically I mean. An attacker can send as much information as he wants over any port he wants, nothing's listening to him to my knowledge.. is a firewall necessary?

Finally, what specifically does the windows firewall do?

Thanks

--Froth 05:38, 5 August 2006 (UTC)

A router/firewall is the only kind of protection you really need (router is better). You can not control the spread of "worms", which are beyond your control of preventing (to a certain degree). Sygate Personal Firewall is a free, no-crap, lean firewall. --mboverload@ 06:19, 5 August 2006 (UTC)

Answering your second question: while it's true that it doesn't make any difference for a closed port, it can make a lot of difference for a port that's open but you do not want anyone else to use. A common example would be the Windows RPC ports (which AFAIK are impossible to close, and were attacked for instance by the Blaster worm). A firewall can also block outgoing connections, if configured to do so; for instance, if a worm on your computer tries to connect to a SMTP server, and the firewall is configured to block these kinds of connections, the connection attempt will be blocked. --cesarb 14:23, 5 August 2006 (UTC)

Firstly, yes there a danger in wireless networking without a firewall. Setting aside ad-hoc networks if you connect to an access point and acquire an IP your machine is now visable to everyone else on that access point, just as if it would be visit to everyone on a wired lan should you plug a cable in. This could mean that any folders you share, or services you run on your local machine that listen for connections on the local lan are now vunerable. Some services do this by default under Windows and a software firewall rejecting connections will stop this. I've not heard of ad-hoc networks being created as an attack, however it was demonstrated this week at Black Hat USA that drivers themselves can have vunerabilities.

Secondly what use is a firewall? Well can you be sure nothing is listening on any ports? Under Windows for example local networking listens. Media Player can listen. The games you play can listen. Instant messengers. Software firewalls tend to prompt you when software attempts to listen, and blocks incoming traffic to services you haven't cleared. The Windows firewall, after XP SP2 provides inbound packet protection and some output program protection.

If you are connecting to the campus LAN/WLAN you cannot be sure of any other machines inside the lan, (and I know as I student I hacked the university mainframe, I cannot believe that nowadays students don't try to hack each other over shared lans, heck when Ping of death arrived a few of us where I worked had great fun crashing each other) so you need all the help you can get. Use a firewall. --Blowdart 15:59, 5 August 2006 (UTC)

http://blog.washingtonpost.com/securityfix/2006/08/hijacking_a_macbook_in_60_seco.html (note this isn't just about macs)

Remote Desktop Connection

I have two computers at home. How can I know the computer's IP address to be able to access the other computer?--203.124.2.6 06:36, 5 August 2006 (UTC)

http://www.no-ip.com/ + UltraVNC = Awesome --mboverload@ 07:03, 5 August 2006 (UTC)

If you are on a home network, you can likely use the computer's names to connect. try that first. If not (assuming you are running XP or a similar version of windows) open the command line (programs>accessories>command prompt) and type "ipconfig /all". Among other things, it will give you the IP of the computer you run it on. Note that this is not the IP which you could connect with from a computer that is not on your local area network. If that still does not do the job (or you are in fact, not on a local area network) let us know what happened and we'll try to solve that. 48v 16:16, 5 August 2006 (UTC)

Memory Upgrade

I would lke to upgrade the memory in my laptop. I know the specification is SODIMM 200 pin PC2100 256 mhz. CL2.5 unbuffered. current memory is 256MB. I would like to upgrade the memory to either 512MB or 1GB. Does the new chip have to have exactly the same specifications as the old one with the obvious exception of size or can I put any larger capacity chip in as long as it is 200 pins?

Will you be replacing the 256MB or just augmenting it with a second DIMM? If you'll be using both at the same time, you'll want the new one to be at least the same speed as the old one, or you'll slow it down. In either case, you're safe using memory that's slower than your current RAM, but you may want to check with the manufacturer of the laptop to see what the upper limits are to prevent overspending or, worse, buying memory that won't work. (Though, if I recall correctly, RAM that's too fast for your computer is usually nice about slowing down if your computer can't handle it). Second opinions anyone? digfarenough (talk) 17:19, 5 August 2006 (UTC)

I once accidentally ordered a SODIMM for a desktop. That was fun. The important thing is that your new RAM chips are 200 pin. I can't remember exactly, but I think there might be a physical difference between PC2100, PC2700 and PC3200, but I can't remember off the top of my head. Just to be on the safe side, try to get PC2100. The maximum amount of RAM depends on your motherboard, but i've got a 4-5 year old PC that can take up to 2Gb, so I wouldn't worry about that. CaptainVindaloo ^{t c e} 20:17, 5 August 2006 (UTC)

There are genuine businesses with a web presence who have a commercial interest in helping you buy the memory you need. Try Crucial for a simple guide, and dealram for a good price. --KSmrq^T 23:53, 5 August 2006 (UTC)

Computer Problem

Have a Dell computer with Windows XP Home edition Verion DSL with AOL membership Keep getting a dialogue box which asks if I wish to Debug gives a numerical line and list error as Ovject expected If I give answer yes the box disappears Later it reappears again same question different line

This is usually thrown by Internet explorer, but occasionally in other places. It generally means that a website or program you are running or viewing has been written in an error. There is not a whole lot you can do. In the options of internet explorer (and maybe on the dialogue itself) there is an option to not ask to debug. I don't know if there is an equivalent for regular programs. Furthermore, try contacting the webmaster/software author and ask them to fix it. By default, those dialogues should not come up (there is a more generic dialogue) did you by any chance install microsoft visual studio or a similar program? That may be why they got turned on. 48v 16:08, 5 August 2006 (UTC)

I think 48v is talking about two different things. From the sound of it, the dialog box you're getting is a javascript error on a website which, as 48v correctly explained, is a problem with how the website is written. You may want to check that your browser is the newest version. I think the error 48v mentions at the very end of that answer is the dialog box that pops up when a program crashes, when you've installed some microsoft developer software. I recall that actually being a separate program that runs in the background, and if that really is the case, you can just disable that from starting up by using msconfig (but be careful with that program, as you can mess things up a bit if you aren't paying attention). Much more likely is that it is a javascript error. digfarenough (talk) 17:24, 5 August 2006 (UTC)

Yes, I was trying to address both. Thanks for clearing that up. 48v 17:54, 5 August 2006 (UTC)

As far as I know, "Object expected" is a (cryptic) error message on Internet Explorer warning about broken JavaScript on a page. The usual setting is to hide the errors; however, if you install some sort of development environment (I can't recall which), the setting changes to stopping and asking whether you want to open the script in a debugger. The message is a symptom of an error in a web page you have open; it's not (at least usually) Internet Explorer's fault. Unless you are a web developer, it's better to just change the setting back to hide the errors; while I do not have access to any computer with Windows installed, I found how to disable it at http://www.microsoft.com/windows/ie/community/columns/ietopten.mspx (it's the last one in the list, "A runtime error has occurred. Do you wish to debug?"). --cesarb 20:53, 5 August 2006 (UTC)

Processor

what is Intel dual core processor?. give me full details? —Preceding unsigned comment added by Python karthik (talk • contribs) 16:26, 2006 August 5

Dual core simply means that there are two CPU's in the same physical 'chip.' They sometimes have their own memory, but share some resources like disks. Intel only means that the chips are Intel brand. 48v 16:31, 5 August 2006 (UTC)

See Multi-core (computing) 48v 16:32, 5 August 2006 (UTC)

We expect you to try google.com or wikipedia.org before you ask here. --mboverload@ 22:18, 5 August 2006 (UTC)

We also expect respondents to be civil. --LarryMac 00:56, 6 August 2006 (UTC)

Yep, that too. --mboverload@ 01:12, 6 August 2006 (UTC)

To suggest that a questioner first search the web or Wikipedia is not uncivil; in fact, it's an excellent suggestion that will often give more accurate and more complete information than posting here, and will also be faster. Furthermore, anyone capable of understanding "full details" of a dual core processor should already know enough to do these searches. This suggests that posting here is an act of laziness, which is a kind of incivility. Such an act reflects badly on the poster, as does not following the directions at the top of the page to sign your question. This being Python karthik's first post, we may attribute these transgressions to inexperience; but the sooner these lessons are learned the better, and that means someone speaking up. (It may be awkward for someone to point out that my crotch zipper is open, but it's much more awkward to leave the problem uncorrected!) In this specific case, I tried both kinds of searches (for 'Intel dual core processor'), and both produced good answers. And lest it seem this is merely my personal opinion, please read the top of the page about How to ask a question, where the first guideline stated is Search first. --KSmrq^T 01:52, 6 August 2006 (UTC)

There are two cores. Check out intel core 2. --Proficient 04:26, 9 August 2006 (UTC)

How did word-processor summarise text?

I remember some years ago there used to be a word-processor that would automatically summarise text for you. It might have been Word. I've never actually seen it or used it myself.

How did this actually work please? Since the computer could not have understood the meaning of the text, there must have been some trick involved. What was it? I have not been able to find anything on the web about this, although I remember reading in newspapers the amusing summaries it could be made to do of well-known books and so on. Thanks. --62.253.52.156 17:55, 5 August 2006 (UTC)

The "AutoSummarize" feature in Microsoft Word does a pretty bad job, usually. I don't know how it specifically works, but there are ways that you can do pretty rough textual analysis if you make a few assumptions about what kind of document it is. It is similar to how I was taught how to read history monographs very quickly—the genre has a fairly reliable form: read the introduction, read the first paragraph of every chapter, read the first sentence of every other paragraph in the chapter, read the last paragraph of the chapter, read the conclusion. In most monographs this will give you an understanding of the argument and the conclusions, and you will skip all of the detailed listing of evidence. I imagine that any summarize function will work on similar structural premises—assuming that in a work of a given format, certain types of information will be in certain spots. It usually works by grabbing sentences from different parts of the document. --Fastfission 17:37, 6 August 2006 (UTC)

Just for fun I decided to run AutoSummarize on Charles Darwin's The Origin of Species using the 6th edition text at Project Gutenberg. The dialog box says that "Word has examined the document and picked the sentences most relevant to the main theme." My guess is that means that it looks for sentences which contain words which are used over and over again or something like that. It allows me to "Highlight key points" in the document, to "Insert an executive summary or abstract at the top of the document", to "Create a new document and put the summary there", and "Hide everything but the summary without leaving the original document." I can specify the length of the summary in terms of the length of the original (default is 25%, which in this case is 49,000 words — a bit long). I changed it to "100 words or less", and the final summary for Origin is:

Species. species.

other species. SPECIES.

called species. species?

DOUBTFUL SPECIES.

to species. species. forms. species. Species very
species. SPECIES.

species. incipient species. extinct species. the species. species. distinct species. species. Whether species
each species. species. species.

the species. twining species.

same species. forms. forms. species. species. form. species. between distinct species. species. aboriginally distinct species. species. species. same species. widely distinct species. forms.

species. forms." extinct species. species. species. species. New species
incipient species. of species. species. species. species. species. forms. aquatic species. Some species,
form. species. classifying species. form." forms. species. species. species.

forms.

So yeah, uh, I guess Word has determined that The Origin of Species has something to do with "species," a word which, after reading that, has lost its meaning for me and looks spelled wrong. I have to say, I'm actually not too impressed by the algorithm... one could imagine ways to have it check itself for heavy redundancy and to make sure that it is forming complete sentences, which this one clearly does not care about (species. species. species. species. forms.). --Fastfission 17:50, 6 August 2006 (UTC)

lolirl --Froth 22:27, 6 August 2006 (UTC)

LOL. --Proficient 04:28, 9 August 2006 (UTC)

Developers, Developers, Developers, .... uhmmm I mean Species, Species, Species, Species :D Shinhan 15:40, 12 August 2006 (UTC)

Evolve! Lite

Back many years ago, I played a shareware game called Evolve! Lite, and it was a huge amount of fun. However, I could not ever get a copy of the full version. By now, the company that made it (FunTek) has gone out of business, and I would still like a copy of the full version. Does anyone know where I can buy or download it? --Zemyla^t 19:36, 5 August 2006 (UTC)

The article on abandonware might help you. You can also try searching for it at online auction sites. --cesarb 20:38, 5 August 2006 (UTC)

Neither one worked. Not even a Google search could find anything. I'm concerned it's gone forever. Which would be a shame, since it was fun. --Zemyla^t 20:55, 5 August 2006 (UTC)

Searching on Yahoo! gave [1], which looks like it has potential. Ebay is worth a shot, too, I guess. Nothing could have disappeared that quickly, though, it's just a matter of how much you're willing to put into digging it out of whatever hole the last few copies fell into. There have got to be ways to track it down if you really want to. Black Carrot 06:41, 6 August 2006 (UTC)

I don't know. If it has very limited circulation in the days before things were very redundantly archives (read: early 1990s, when the internet was young, connections were slow, and hard drive space not so cheap), it could be pretty hard to find, especially if it would have difficulty running on newer machines (i.e. if it used for/next loops for its timer structures, was DOS only, and so forth), which would make its likelihood of being migrated to newer machines more rare, and the chances of finding it pretty slim. The only referneces of it I can find on the web are of the sort you posted above: one or two text file links advertising it, which makes it sound like it harkens from the days of BBSes, a scary prospect for someone trying to find it today. --Fastfission 19:26, 6 August 2006 (UTC)

Pray that it shows up on clasp --Froth 22:30, 6 August 2006 (UTC)