if i'm part of a network can people see my computer files, or what i'm doing online?

Question

my old roommate connected our computers with a network so that we could both be online at the same time, and use the printer. but i'm not very computer smart and when i looked at my internet security it says that there is a trusted computer, is that my roommates and can i erase it because it's on every location, like home, away and office, and even the new one i just made today. i don't know what i'm doing please help
plus i just set up a new internet service today and it says that i'm part of that network as well, so can other users of that internet provider see what i'm doing, and do i have to be connected to that network to be able to use the internet. i don't want people to be able to see stuff like when i look at my bank account and stuff.

Answer 1

I am assuming you are using Windows? If you stick a computer with Windows on it to any network with others Windows computers those other people will have to know an administrator password or password to an equivalent account to get into your computer remotely. I am a network administrator and I routinely look into machines for various reasons, its also called rooting the machine, or gaining root level access to the C: drive. If you have no Administrator password set then people can easily get in provided they are somewhat computer savvy. I suggest you set passwords for all accounts, especially the Administrator account if the computer is on a large network with other people that you do not know. If you are on a small home network or small LAN you have setup in a room then there really is no way for people to get in because they have no physical connection to your computer. If you are required to join the computer to a Windows Domain or someone has already done this to your computer, then the Administrator of that network has full access to your computer regardless of what passwords you set. If you have passwords set to get into your computer for all accounts and its your own computer and its not a member of a larger domain then your probably pretty safe. Make sure Windows Firewall is turned on and that will shut off all the ports that a hacker might try to use to gain access. If this is a small network hooked to a router and a high speed internet provider such as a cable modem or DSL, you are fairly safe because the router has a firewall, and also windows has a firewall too.

Answer 2

Follow Papo's suggestions to secure your pc!



To know what you have shared you can use Windows Explorer and type your own computer name as follows:



\\computername



To get the computer name just right click "My Computer" > Properties > Computer Name tab > Full Computer name.



If you don't want to or need to share your drives go to Windows Explorers and for every folder you see a blue hand underneath just:

1) click on the folder to select

2) right click to get options.

3) select "sharing & security" and "Do not share this folder"



This should take care of people reading your data by just mapping your drives.



Also, check that they can't logon to your computer either directly behind the computer (console) or remotely with Remote Desktop



1) Directly behind the computer will require knowledge of a local user/password. This is also true for Remote Desktop

The best way to do this is by changing all local account passwords.



You can find any other remote control software running by typing at the command prompt (START>RUN>NETSTAT)



It will tell you what is open and what is listening. If you find a port 3389 it means you have Remote Desktop open and waiting for someone to connect.



If you have a port in the range of 5800-5900 you have VNC remote control software installed.



The port number is the numbers at the end of the foreign address after the ":"



With VNC, just go to the control panel> add remove programs > remove VNC from the list.



There might be other stuff that can allow access to your computer. If the computer is your own, just install a free firewall. Close applications and ports when asked, but make sure you understand you are closing by researching on the internet what is used for. There is plenty of info out there to help you make a decision.



I don't think your old roommate is a hacker and just wanted to make your life easier, but just check for malware and keyloggers.



Check these software:

Comodo BoClean (Antimalware)

AVG Anti-Spyware

AVG Rootkit

ZoneAlarm, PCTools Firewall, Comodo Firewall



Finally, if you are behind a router you will have an extra layer of defense, as your computer will not be directly connected to the Internet.



There are many thing more to look for, but these are the basics for home users.



Cheers!



Reference: Certified Information Systems Auditor w/12+ yrs of experience in large corporate environments.

Answer 3

Short answers. Yes.

Longer Answer.



Most of the traffic on a network is clear text and you'll need some tools like Ethereal to be able to see what's going on on a network. Also, you need to be quite computer saavy to make sense of it, but it can be done and it is being done by malicious hackers. Trying to figure out what you're typing off a document on a shared drive based on snooping it's not possible. However, writing a document in an unsecured website, yeah, it's possible to figure out your love letter from a network snoop.



Something can be done. First, make sure that you have password on anything and do not have a unsecured shared folder, make sure that they're all authenticated. Second, make sure that if you're sending sensitive information is done on an encrypted connection (https or secure shell). Third, make sure that all your WiFi connections are secured. Fourth, you do have a firewall, virus protection and spyware protection if you're using a Windows PC is not it? (if you're using an Apple or Linux computer, make sure that you are current in your patches)

Answer 4

Defenitely, your roomate can see what you are doing. There are programs that can be use to inspect the local network and even to have a screenshot of your computer in realtime.



The thing is that your roomate had creates a peer to peer network at your home so everybody has the same privilage, so you can do the same things to them