Thread: Dlink glb 802c firewall configuration

Hi,

I am using Dlink GLB 802C ADSL Router to connect to BSNL Broadband.

Ever since I purchased this router I have been using it in Bridged Mode.

Since I use Linux (openSUSE 11.4) operating system by default all ports are in "stealth mode" even in Bridged Mode

which I confirmed at grc.com's sheild up test ........ Now that I have another PC at home

I want to connect it to my existing network via a switch.

Therefore I configured the router in pppoe mode successfully and then went to grc .com to get the ports checked.

First of all most of the ports are closed ....they are not in stealth mode. Only a few of them are in stealth mode.

Before purchasing this router I used Dlink 502T in pppoe mode & found all the ports in stealth mode.

Please tell me how to make all the ports stealth.

default all ports are in "stealth mode" even in Bridged Mode

As Windows OS user, I understand, all ports are OPEN in above "bridged" mode.
Advised to use antivirus/Firewall applications to protect the system from virus/malware etc.

Use Portforwarding in PPPoE ( "always On") mode in the modem/router
for specific applications.

Para two:.
What is the difference?
(a) ALL Ports Open/Closed/Stealth?
(b) All ports stealth mode? ( about 60,000 ) You dont' see the port number ? where ?
(c) All ports closed?
(d)What is the need for "stealth"?

http://www.canyouseeme.org/

Thanks for your reply.

What is the difference?
(a) ALL Ports Open/Closed/Stealth?

I am no expert but what I have learned in the past few days Googling is that ..... the difference between "Closed" & "Stealth" is

Closed means that the port is visible to others but they cant connect it to because it is closed &

Stealth is like stealth ..... invisible.

(b) All ports stealth mode? ( about 60,000 ) You dont' see the port number ? where ?

As I have mentioned in my first post, its at grc.com. I am not allowed to post links until I reach 15 posts or more.

If you want to find out about grc.com search grc at Google ....

> click on "Home of Gibson Research Corporation" that will take you to grc.

This is what I did

Services (top of page) > Sheildsup >Proceed > All Service Ports which tell me the status of the ports of my ip.

Its not 60,000 that grc tests. This is what is written there :

This Internet service ports "grid scan" determines the status — Open, Closed, or Stealth — of your system's first 1056 TCP ports

(c) All ports closed?

Yes, most of them are closed & a few stealth according to grc.
thi

What is the need for "stealth"?

I agree that I am a bit over cautions but that's how it is !!!

I tried to configure port forwarding in order to achieve stealth but frankly couldn't do it.

Your help is needed.

A firewall normally solves the problem, in my case norton.

I'm over cautious too.

I am no expert in opensuse, but I found out there is a firewall available.

Originally Posted by axel

A firewall normally solves the problem, in my case norton.

I'm over cautious too.

I am no expert in opensuse, but I found out there is a firewall available.

Well, all ports are in stealth mode in openSUSE (by default).... no worries about that but

the question remains why is this router not making them stealth ?

GLB 502 T did make them stealth ..... it was very easy .. just select firewall & Nat & done !!! Stealth
achieved.

I really feel that DLINK should consider opening an IRC channel for help.

Their present policy is like ....."product is sold ...now bye ..bye".

Their present policy is like ....."product is sold ...now bye ..bye"

.

They have uploaded the user manual specially on my request. for this model.
If interested link can be given.

2. Try the web site auditmypc.com details about all ports.

3. Unless the web site says use this port which is rare ,
could not understand your requirement. Hope @axel will explain further.

4. Since using Windows7 Pro and MSS , i am not using any firewall/
application. earlier ZONE ALARM.
Check firewall applications here:
FileHippo.com - Download Free Software

5. I basically use Internet for Email/cricket score /Forums participation/VOIP and SKYPE etc. So no knowledge about "Stealth" web sites / and aircraft/helicopters/ of U.S which radar cannot detect.

Sometimes: 8080 is added and also for FTP sites..

from GRC site:

When a test is initiated by any system behind a NAT router, we are testing the public-side security of the router itself and not the security of the individual machines which are located behind and protected by the router.

in pppoe mode it is the modem which decides what ports are open/closed/stealth to internet while in bridge mode your OS determine this.that is why opensuse in bridge mode will pass GRC test but not in pppoe mode.

Although the router may be protecting the machines behind it, it might not be protecting itself without your deliberate closing of remote "WAN" administration ports.

in pppoe mode it is the modem/router which is most vulnerable & not the computer itself.an attacker can infiltrate modem to modify its dns cache/iptable to route traffic from your computer through a 3rd party site thus accessing your data but even then if it is a https/secure connection hacker has to break the encryption first which is extremely difficult.

in the end i would just like to say this:there is no need to be so paranoid about security.no brilliant hacker is going to waste efforts on ordinary things & unless you are doing something seriously illegal then no security/govt agency either.closed port is as secure for you as stealth port because if a real hacker decided to hack your computer then stealth or closed port it won't matter.

They have uploaded the user manual specially on my request. for this model.
If interested link can be given.

I found this one (I cant post links yet)

Code:

ftp://support.dlink.co.in/broadband/GLB-802C/manual/GLB-802C%20User%20Manual.pdf

on their website & on the CD that I got with the router

They uploaded a different one on your request ?

Yes...I need that please give me the link.

Try the web site auditmypc.com details about all ports.

Here it is

Code:

Firewall results

Congratulations! None of the ports you scanned for were open!

@whitestar_999

I have changed the default login details of my router ...... that's all I could do. Thanks

http://www.indiabroadband.net/bsnl-b...tml#post302946 (GLB802C user manual)

http://www.indiabroadband.net/attach...ser-manual.zip

Download QIG&User Manual.zip from Sendspace.com - send big files the easy way 1.29 MB

check this link :http://www.indiabroadband.net/comput...tml#post315289 (Monitor Screen Shot)

you can upload and give the link omitting http:// www
( no space dots *** etc )
sendspace.com/file/136min

@essbebe

Useful links there .....

But the problem is non of them describes how to configure the "Global Firewall" .

I am quoting from the help that is provided within the router's configuration web interface

follow these instructions to configure global firewall settings:

If the Firewall Configuration page is not already displaying, click the Services tab, and then click Firewall in the task bar.

I find no "Firewall" link in the Services tab

Here is my Services page

Code:

i851.photobucket.com/albums/ab73/img2010_album/Screenshot-1-3.png

What are the other options ? in same page ? arrow down ?
India Broadband Forum 20.5 KB

Sorry about that ....here it is

Code:

i851.photobucket.com/albums/ab73/img2010_album/Screenshot-GLB-802CConfigurationManagerGUI-MozillaFirefox-1.png

I have downloaded the latest firmware from D-Link's support page .... just in case.

Haven't upgraded the firmware yet.

Waiting for your confirmation.

try the NAT rule :

Here ........

Code:

i851.photobucket.com/albums/ab73/img2010_album/Nat.png

I don't have this router
you have to select a rule add next page etc and then post
the result./comments.
May be @axel or @whitestar_999 can help.
[IMG]
http://www.indiabroadband.net/attachment.php?attachmentid=9019&stc=1&d=130616298 3[/IMG]

Originally Posted by essbebe

I don't have this router
you have to select a rule add next page etc and then post
the result./comments.

Can I upgrade the firmware ?

May be that will make the Firewall link appear in the Services page as mentioned the help documentation?


I have never done this before. What are the precautions (if any) that I shoul take before going for the upgrade ?

Stealth mode can be attained by installing a firewall if previous (default) configuration is lost...

If you don't already have these...check

http://tr.opensuse.org/YaST_Firewall ( http://old-en.opensuse.org/YaST_Firewall )

http://en.opensuse.org/SuSEfirewall2

I use ubuntu...it has ports in stealth mode by default.

@axel

My Linux box is stealthy already. openSUSE's firewall is configured properly.

Frankly there is nothing that I did it was stealthy by default.

I am concerned about my WAN/Router Side .....points that whitestar_999 has

pointed out.

All right I thought that backwards...

You can forward the ports to a non existent ip address.

All ports doesn't have to be stealth and its unnecessary...

As grc faq says you need to worry about port 113 the identification port.

I am concerned about my WAN/Router Side .....points that whitestar_999 has
pointed out.

@netkid,it seems like you missed the latter part of my reply.

in the end i would just like to say this:there is no need to be so paranoid about security.no brilliant hacker is going to waste efforts on ordinary things & unless you are doing something seriously illegal then no security/govt agency either.closed port is as secure for you as stealth port because if a real hacker decided to hack your computer then stealth or closed port it won't matter.

anyway under admin tab go to management control.disable wan access for all protocols so that your modem can only be accessed by computers within lan.i.e.having ip 192.168.1.x