Help - Ping request could not find host ... DNS problem

 You may have seen this message before:

Ping request could not find host www.cnn.com. Please check the name and try again.

There could be many things that can go wrong with the networking that caused this. Ultimately it is very likely the DNS that is the problem.

Firstly, let's simply go through a few troubleshooting options - just to rule out it is not because of the them. Do one step at a time, check the WiFi and if it works, don't need to progress to the next step.

1. For older laptops, believe it or not, there is actually a slider switch to click the WiFi on or off. Check this if you have it.

2. On Windows, on the TaskBar, ensure that the Wifi (not any particular Wifi network yet) itself is turn on. The WiFi can be either On or Off or Flight Mode or something else.

3. Check that the Wifi is connected to a particular WiFi network. Make sure it says Connected and Secured. And there is no yellow exclamation mark.

4. Open up CMD command terminal, type:

ipconfig  /release 

ipconfig /renew

ipconfig /flushdns

5. Reboot the computer.

If all else does not work, it is now time to suspect the DNS.

The DNS, in layman's term (you can Google for the exact definition), is directory service that lookup the URL you type and translate to an IP address. Its like a Post Office that receives an address and then go to that address. Our computer need to have the address of the DNS server itself - eg. we need the POST OFFICE's address, so that we can give them our letter.

The so somehow, our computer needs to know which DNS IP address to use. Most of the time, this is hidden from the user, that is why most computer user don't have to deal with it and so don't understand it. It can be automatically set on the modem or router, and also optionally automatically set on the Windows network settings.

So why should there be a problem when the DNS working nicely behind the scenes one day, then the internet is not working the next day? There could be many answers, but a recent experience has shown that some software, including VPN software can go it to the network settings and change the DNS address.

Hence one more solution to above error message is to change the DNS address on the Windows networking level. Whichever Windows version you have, 

- find your own way to the 'Network Connections' page or 'Change Adapter Settings' and you can see a page with a list of your network (ethernet, Wifi, VPN) adapters. 

- Right click on the Wifi adapter, if you are using the Wifi adapter.

- Choose 'Internet Protocol Version 4', and click on the Properties

- Go to the section called 'Use the following DNS server addresses', and add 'Preferred DNS' and 'Alternative DNS'

Some of the free DNS addresses are:

Quad9 - known for security

9.9.9.9, 149.112.112.112 (Secured)

9.9.9.10, 149.112.112.10 (Unsecured)

Google - you know them

8.8.8.8, 8.8.4.4

Cloudfare - known for speed

1.1.1.2, 1.0.0.2

OpenDNS - mature and known for security, 

208.67.222.222, 208.67.220.220

CleanBrowsing - known for parental filtering

185.228.168.168, 185.228.169.168

How to use hotel wifi safely

The links below are to a few articles about how to use FREE hotel wifi safely. In summary:
1. There is no real safe way to use hotel wifi - Be Warned
2. Using the hotel LAN (not wifi) is even worse
3. Using VPN provides a layer of protection since it hides the data transmitted from your device to the internet. However it still doesn't prevent a trojan from being planted on your system and accessing your file system.


http://us.norton.com/yoursecurityresource/detail.jsp?aid=free_wifi

http://traveltips.usatoday.com/safely-use-wireless-internet-hotels-2970.html

http://www.wikihow.com/Stay-Safe-While-Using-Hotel-WiFi

http://blog.hotspotshield.com/2013/06/17/hotel-wifi-security/

http://forums.cnet.com/7723-6132_102-565662/how-can-i-use-free-wifi-in-hotel-safely/

How Does a Router Protect

I posed the question to myself of "How does a router protect" based on my curiosity on what something I remembered that a router is already acting as a firewall. So I googled on the topic and found some very interesting results. The google results are listed below. But first, my summary is this:

1. Router uses NAT to protect computers connected behind the router.
2. The Router NAT technique protects outside attempts to talk to the computers behind the router - ie blocks inbound traffic.
3. But Router NAT does not by default block outbound traffic. A computer already infected may call outside to its base and get information or commands back.
4. Some say router is enough, other say software firewall is necessary.
5. Router NAT does not protect against computers or configuration which uses:
- VPN - to connect into a company's network from home securely.
- Port Forwarding - required when running a web server.
- DMZ - used by gamers sometimes to enable playing network games.
Any of these will by pass the NAT protection mechanism and expose the home computer and others on the network.

Setting up Cascading Router (LAN to LAN or WAN to LAN)
http://www.linksys.com/au/support-article?articleNum=132275

Using A Modem and Router combination
Internet -> ADSL Modem -> Router -> Device

(WAN stands for Wide Area Network and is the IP address given to you by the Internet service provider)

Double Nat
http://www.howtogeek.com/255206/how-use-your-router-and-isps-modemrouter-combo-in-tandem/
To overcome the Double NAT problem, one way is to use Bridging.
Switch the Modem into Bridge mode.
"Bridging is simply an old networking technique that transparently links two different networks."
Consequences:
- the modem will become a modem only, with have no effective routing functions.
- no devices can be connected directly to the modem unit
- no devices cab be wirelessly connected directly to the modem unit

https://www.cnet.com/how-to/home-networking-explained-part-8-cable-modem-shopping-tips/
On the other hand, it's a little bit more work to add a Wi-Fi router to your existing gateway.
1.you need to connect the new router's WAN (or Internet) port to the gateway.
2.make sure that the new router has a different IP address from that of the gateway. (Chances are they are already different, but if not, you will need to change that of the new router before plugging it to the gateway.)
3. And finally, apart from turning off the Wi-Fi network of the old gateway, if you want the new router to get the WAN IP address, you will need to configure the gateway to pass that to the router. The means of doing this varies depending on the gateway itself. The passing of the WAN IP address is only necessary if you want to set up customized Internet-related services, such as those mentioned in Part 9 of this series.


The Ultimate Modem/Router Setup Thread
http://www.tomshardware.com/forum/33700-42-ultimate-modem-router-setup-thread

When is an NAT router inadequate protection?
http://www.dslreports.com/faq/9787
temporary mirrored at:
http://xtechnotes.blogspot.com.au/2012/04/when-is-nat-router-inadequate.html

How Does A Router Protect My Computer?
http://www.askageek.com/2006/10/17/how-does-a-router-protect-my-computer/

A Router Can Protect your Computer
http://www.compukiss.com/articles/a-router-can-protect-your-computer.html

To what extent does the firewall on a router protect you?
http://askville.amazon.com/extent-firewall-router-protect/AnswerViewer.do?requestId=747083

How does a router protect you?
http://forums.cnet.com/7726-6035_102-5152551.html

Does my router have a firewall or not?
http://ask-leo.com/does_my_router_have_a_firewall_or_not.html

How do I protect users on my network from each other?
http://ask-leo.com/how_do_i_protect_users_on_my_network_from_each_other.html
info on dual router layer / double NATing architecture.

When is an NAT router inadequate protection

This article is mirroring the article at : http://www.dslreports.com/faq/9787 . The dslreports.com website seems to be down, and has no expected online time.

24 Apr 2012 - The original site seems to be working again. So go to http://www.dslreports.com/faq/9787

The main points of the article is extracted here:

----------------------------------------------------------------------

When is an NAT router inadequate protection?

1. Depending on your network configuration, an NAT router can be a very cost-effective, inexpensive and reliable addition to your computer's security. At US$40 to $70, they can be worth getting even if you only have one computer.

1.1 You should definitely run a software firewall on any computer that connects to AOL using a different Internet Service Provider (AOL's Bring-Your-Own-Access plan or AOL MAX using an ISP) no matter what kind hardware firewall or NAT router you have.


1.2 If you have to turn on port forwarding or the DMZ to run servers or other applications you should consider either a software firewall or a more expensive SPI firewall.


1.3 Generally software firewalls provide valuable additional protection that supplements the protection provided by NAT routers and SPI firewalls.

Ideally a software firewall should be an additional layer of protection behind an NAT router or external firewall. For homes a free version of a software firewall is normally adequate for this additional layer of protection.

- ZoneAlarm Free
»www.zonelabs.com/store/content/home.jsp
Look for the free version / free download, and continue to ask for it rather than the Pro version.

- Sygate Personal Firewall
»download.com.com/3000-2092-10049···g=button

- Kerio Personal Firewall Limited Free Version (Sunbelt Kerio Personal Firewall)
»www.kerio.com/kpf_download.html
Look for the "limited free" version.

For businesses, computers running public servers, and computers on wireless networks, a paid-for version of a software firewall provides more protection by allowing more customization and more precise control.

2. In selecting an NAT router, software firewall, or hardware firewall, consider its logging and alerts capabilities.

3. If the router or firewall is wireless, secure the wireless interface.

4. Firewalls are not a replacement for adequate backups of data. (Firewalls don't protect against real fires, or burglars.) /faq/10194

5. Other security precautions still need to be taken. For example, operating systems and anti-virus software need to be properly installed, configured and updated.

6. There is no hardware or software you can install that will protect against massive amounts of traffic jamming your communications lines. "SPI firewalls" only protect against certain types of denial of service (DoS) attacks involving malformed packets, or protocol sequence violations and vulnerable software.

7. Historically, the original network firewalls did not do packet inspection. They were rule based, using tables of permitted IP addresses and ports. Packet inspection is not historically in the definition of firewalls.

8. The NAT firewall was a major advance. It limited inbound traffic based on the basic state of communications with the external IP address. Outbound traffic triggered permission for inbound traffic.

9. This is basically how a pure many:1 NAT router works. M:1 is the kind of router commonly used for home and SOHO users to provide a connection for many local computers using one public IP address.


10. Port forwarding bypasses the state table and that source of protection provided by the NAT router. Port forwarding (on a pure NAT router) causes almost all traffic that arrives at a particular port to go to a particular local IP address. (Basic packet filtering is the only protection for the port.)



11. The DMZ should be totally avoided on most NAT routers.

A DMZ is not normally required, provided you know your software. Check the software vendor's website, or email their support area, or search here in BBR, to find out what ports you need to set as trigger ports for which ports, or which ports to forward.

If you really do need a DMZ, use a device that treats the computer in the DMZ as though it was an untrusted computer outside your local network. Ordinary NAT routers do not normally provide this type of DMZ; they normally just forward all unsolicited traffic to the machine in the DMZ, leaving it with no NAT protection.


Here are some security testing sites: /faq/5503

Here is more on securing your home computer: /faq/8463

Here is more on securing a wireless router: /faq/8698

For discussion about your individual circumstances you can post a message in the BBR Security Forum here: /forum/security

Privacy - How To Cover Your Web Surfing Tracks and Internet Presence

When we go Web Surfing or Browsing the Internet with a web browser, we may think it looks like:

                Me  ->  Website

but in fact it is more like

               Me  ->  My Internet Service Provider (ISP)  ->  Website

When a web page appears on your computer, there is no magic - information is passed to and from Me, ISP and Website. Basically, anything about you that can be known, your IP (internet address), location, name you  sign up with, etc, can be obtained by ISP and Website and by others.


There are many valid and legal reasons why people would like to keep their privacy from their ISP and the Websites they visit. So there are ways to Not Reveal to your ISP which websites you visit, and Not Reveal to the Websites where your real location is.

Using VPN

Hotspot Shield - This software connects your computer via a VPN to the servers of HotSpot Shield which then visits the Websites. It looks like this:

               Me  --->           My  ISP              HotSpot Shield Servers -> Website
                              ----> VPN Tunnel ---->

So the Website thinks the visitor came from HotSpot Shield servers, instead of coming from you.
The ISP sees encrypted data and does not know which Website you are requesting to see.

Drawback: Theoretically your information is still known by HotSpot Shield servers. Well you have to trust someone in the end......

Here is a guide to set up VPN in Windows 7
http://www.pcworld.com/article/210562/how_set_up_vpn_in_windows_7.html

VPN Gate - An experimental VPN setup in Japan. Free to join.
http://www.vpngate.net/en/



Using Proxies

From a very high level, proxies work in a similar way to VPN. The key difference is that the traffics is not necessarily encrypted. However, the request to a website is send via another server in the middle, so that the destination website does not know it came from you. Since our information passes through a web proxies, we must trust those web-proxies that we use.

Here are some web-based proxies:
- Proxify - proxify.com

- Anonymouse - anonymouse.org
- Hide My Ass - www.hidemyass.com


There are manual proxy servers which require your browser to be configured to make use of the web proxy. The following sites maintain a list of proxy servers:
- Proxynova - www.proxynova.com
- Hide My Ass - www.hidemyass.com


Other Ways

There are many other ways to cover your tracks. This site http://www.how-to-hide-ip.info/hide-ip-tools/ has a collection of tools that cover a variety of ways, such as:

• Tools on your PC for hiding IP
• Using Proxy in your Web Browser
• Proxy Sites
• Proxy Lists
• IP checking sites
• VPN services

Covering Web Browsing activities: using Tor www.torproject.org

In fact TOR (The Onion Router) is an ongoing and mature project with a lot of features that enable anonymity on the internet. TOR comes with a Bundled Browser with TOR preconfigured. TOR also has something for smart phones (see below).

For Smartphone, Mobile, Android systems: 

• Orbot - this is based on the Tor technology but available to Android on smartphones.

Email Anonymity
Use the following to protect mask your identity when sending emails:
- Anonymouse - anonymouse.org
- Hide My Ass - www.hidemyass.com

When you go to any these sites, your browser security may flag some of these sites to be suspicious. This could be due to their nature to hide identities or the fact that they are suspicious. In any case, make your own decision before visiting these sites.

How to Connect to Telstra Remote Working Solution (TRWS) on a corporate laptop.

This short guide shows how to setup VPN connection using a laptop configured to use Telstra Remote Working Solution.

Before going through this setup, the following pre-requisites need to be satisfied:

1. Your laptop has the TRWS installed and is running Windows.
2.  The connection is intended to use your laptop to connect to your home wireless network. The TRWS software will then provide a VPN tunnel through your home WiFi network, into the public internet, and securely into your corporate network,
3. Your home WiFi network is already setup and you have these information: WiFi SSID, WiFi Security Mode and WiFi password.
4. RSA SecureID token Device. This device is on all the time and a number is displayed, which changes after a certain amount of time.

The following steps will help setup the connection for the first time. The login steps below need to be done each time you login again.

1.    1.      Switch on Laptop.

2.   2. Look for the physical switch for the WiFi on the actual laptop. Its location is different for different laptop  models. Ensure this is switched on.

3.    3. When the laptop booted and is ready for work, then open up the TRWS application  either by:

i)                    Start – All Programs – Telstra – TRWS; or

ii)                  Click on the TRWS icon on the desktop.

4.    4.   From the TRWS, click Settings – Login Information.

5.    5.   In the Login Information, fill in the Username, Password, click Save Password and select the relevant country. Click OK.

6.      6. Go back to the TRWS dialog, click Settings – Connection Strings.

s

7.   7.   In the Connection Strings, click on the WLAN.

8.   8.   Under the WLAN tab, select the Device for your WiFi hardware on your laptop. Then click the Add button. The Add Personal Network dialog appears.

9.  9.    Fill in the SSID box and the Security box with the WEP, WPA or WPA2 password. The type of Security would depend on how your home WiFi is configured.

10  10.  Under the SSID, there is a checkbox called “Non-Broadcast”. If your WiFi Network is usually hidden, then please tick this checkbox. Click OK to finish with the Add Personal Network dialog.

11  11.  Going back to the WLAN tab, your WiFi network should be listed (not necessarily connected) in the Personal Networks box.

12  12.  Put a tick in the “Display all WLAN networks” box.

13  13.  At this stage, if the home WiFi is hidden based on SSID, make sure it is set to Not Hidden or Unhide. It can be set to Hidden again at the end of this guide. You may need the help of your home WiFi administrator for this.

14  14.  Click OK to finish with the Connection Strings dialog.

15  15.  At the TRWS main dialog, your home WiFi network may appear in the list under Phonebook – Available Networks. Double click on your WiFi network in the list.

16  16.  If it does not appear in the list, then under the menu, select Bookmarks – select your WiFi list under there. If it does not appear here either, then check that the WiFi network is Not Hidden.

17  17.  Also, to check that the WiFi adapter hardware inside the laptop is working, under the Phonebook – Available Networks, there should be a list of WiFi networks possibly from your neighbours. This just shows the WiFi in your laptop is working.

18.  If the previous steps have been successful, that just means that the laptop is connected to your home network. To establish a VPN (Virtual Private Connection) to your company,  the following extra steps are needed. A dialog to establish a VPN appears. Click OK. Go to step 21.

     19.  If the above dialog does not appear automatically after 5 minutes of connection, then go to the Taskbar in Windows and look for a yellow padlock icon. Double click on this to open up the VPN client connection status.

      20.  In the VPN client status dialog above, double click on the connection entry, eg “cbamras”. This will open up the dialog in step 18. Click on the network option and click OK.

      21.  Another dialog appears to login to the VPN. The user name is “r” plus your normal username in the company. The password is your normal password in the company plus the numbers in the RSA Secure ID token. These instructions may differ for different corporations.

22.  At this stage you have connected to both the internet and your corporate VPN.

      23.  Some other notes:

       -  to browse the internet, you may need to give your corporate username and password, if it a corporate web proxy is used.

24. How to Reset Network password
On the occasion that your user password has been changed at the network, and your laptop password is out of sync, here are the steps to change the password on the laptop:
- Switch on the laptop and boot until the Windows login prompt.
- Login to Windows using the old password.
- Connect to the office network using Telstra RAS as described in this article.
- Once the laptop has established connection with the office network, the press Ctrl-Alt-Del and Lock the computer.
- Unlock the computer by   Ctrl-Alt-Del  and then enter the old password.
- Then press again Ctrl-Alt-Del and Lock the computer.
- This time, unlock the computer using the new password on the network.
- The laptop should now have the same password as the network.