Subnetting, Cyber Security, Ethical Hacking

[Haeking]

I was wondering if anyone would be willing to teach me more and more into the networking aspects of internet technology, I would like to be able to have a better defense other than my ISP for if my network were to be hacked, and I would also like to learn if so possible for ethical hacking 

[Lurick]

Check out CBT Nuggest on YouTube for some basic knowledge, I think they cover all the points you were looking to hit.

[vorticalbox]

>install firewall

>block all income connections 

>profit

[Hiitchy]

2 minutes ago, vorticalbox said:

>install firewall

>block all income connections 

>profit

Every time someone says block all incoming connections this is all I can think of

 

[Haeking]

Just now, Hiitchy said:

Every time someone says block all incoming connections this is all I can think of

 

I feel you dude that moat would be impenetrable 

[RAM555789]

Just to let you know subnetting is literally just splitting up IPv4 addresses 0.0.0.0 through 255.255.255.255 into smaller networks using subnet masks.

[Haeking]

1 minute ago, RAM555789 said:

Just to let you know subnetting is literally just splitting up IPv4 addresses 0.0.0.0 through 255.255.255.255 into smaller networks using subnet masks.

Yea I know, I want to understand the process more. If you'd have the free time to teach me I'd love to learn 

[RAM555789]

Also your not going to be able to have a better defense than your ISP. They literally spend millions if not billions building infalstructure, firewalls, software for security, ect.

[vorticalbox]

11 minutes ago, Hiitchy said:

Every time someone says block all incoming connections this is all I can think of

 

Back in a time where hardly anyone could swim or rich enough to have access to a boat it would have been. 

 

blocking incoming connections isn't the be all and end all but it certainly helps, then you only open ports you need. I open 8300 on my Ubuntu desktop for access to minidlna. 

[Unhelpful]

12 minutes ago, RAM555789 said:

Just to let you know subnetting is literally just splitting up IPv4 addresses 0.0.0.0 through 255.255.255.255 into smaller networks using subnet masks.

Ex/

192.168.0.0 With the Subnet mask of 255.255.255.0 or /24 (meaning 24 bits turned on, as seen below) gives you the whole fourth octet.

 

11111111.11111111.11111111.00000000 (/24 is the amount of 1's) Convert Binary to Decimal and you get 255.255.255.0

 

This gives you the following usable IP Addresses: 192.168.0.1 - 192.168.0.254. The Subnet Address is 192.168.0.0, and the Broadcast address is 192.168.0.255. These IP Addresses are non-assignable. 

 

Ex2/

192.168.0.0 With the Subnet mask of 255.255.255.128 or /25 (meaning 25 bits turned on, as seen below) gives you half of the fourth octet.

 

11111111.11111111.11111111.10000000 (/25 is the amount of 1's) Convert Binary to Decimal and you get 255.255.255.128

 

This gives you the following usable IP Addresses: 192.168.0.1 - 192.168.0.126. The Subnet Address is 192.168.0.0, and the Broadcast address is 192.168.0.127. These IP Addresses are non-assignable. You have a total of 126 assignable IP Addresses, 192.168.0.1 - 192.168.0.126.

 

You can respond to me if you have any questions @Haeking, I probably won't see it if you don't hit "Reply."

[RAM555789]

IPv4 is 32-bit and has a limited amount of addresses of 4,294,967,296. Your computer gets an IPv4 address, and IPv6 address, and IPv6 is 128-bit and theres 3.4×10³⁸ IPv6 address available to the world. That's a very very large number. Your computer also has a MAC addresses. You have two types of devices in basic networking that use IP addresses and MAC address, and that's switches and routers. Switches care about MAC address while Routers care about IP addresses.

[RAM555789]

4 minutes ago, JoeyDM said:

Ex/

192.168.0.0 With the Subnet mask of 255.255.255.0 or /24 (meaning 24 bits turned on, as seen below) gives you the whole fourth octet.

 

11111111.11111111.11111111.00000000 (/24 is the amount of 1's) Convert Binary to Decimal and you get 255.255.255.0

 

This gives you the following usable IP Addresses: 192.168.0.1 - 192.168.0.254. The Subnet Address is 192.168.0.0, and the Broadcast address is 192.168.0.255. These IP Addresses are non-assignable. 

 

Ex2/

192.168.0.0 With the Subnet mask of 255.255.255.128 or /25 (meaning 25 bits turned on, as seen below) gives you half of the fourth octet.

 

11111111.11111111.11111111.10000000 (/25 is the amount of 1's) Convert Binary to Decimal and you get 255.255.255.128

 

This gives you the following usable IP Addresses: 192.168.0.1 - 192.168.0.126. The Subnet Address is 192.168.0.0, and the Broadcast address is 192.168.0.127. These IP Addresses are non-assignable. You have a total of 126 assignable IP Addresses, 192.168.0.1 - 192.168.0.126.

 

You can respond to me if you have any questions @Haeking, I probably won't see it if you don't hit "Reply."

They taught us a much easier way in the Army after we learned this way but its hard to show without a paper and pencil.

[Haeking]

6 minutes ago, RAM555789 said:

They taught us a much easier way in the Army after we learned this way but its hard to show without a paper and pencil.

can you teach me the basic way the army taught you 

[RAM555789]

Also to add on to what he said the numbers you match up with the binary is 128 64 32 16 8 4 2 1 so the bits turned "off" that are zero are you network, once I hit 256 I start to affect the third octate so 0.0.0.0 to 0.0.1.0 is 256 addresses, 0.0.2.0 to 0.0.0.0 is 512 address and so on.

[Unhelpful]

9 minutes ago, RAM555789 said:

They taught us a much easier way in the Army after we learned this way but its hard to show without a paper and pencil.

Yeah I think I know the easier way. But I don't like it for teaching tbh, because it doesn't teach the why it works. It's important to know the 'Why', 'How', in addition to the 'What'.

 

Below is an easier way to do this within the fourth octet:

255.255.255.0

255.255.255.128

255.255.255.192

 

256-0 = 256 Addresses. -2 gives you your usable. 254 usable.

256-128 = 128 Addresses. -2 gives you your usable. 126 usable.

256 - 192 = 64 Addresses. -2 Gives you your usable. 62 usable.

 

This method is easy, but does not explain why, only the what... So I veer away from it for teaching.

[Unhelpful]

1 minute ago, Haeking said:

can you teach me the basic way the army taught you 

 

8 minutes ago, RAM555789 said:

They taught us a much easier way in the Army after we learned this way but its hard to show without a paper and pencil.

If you actually want to learn I would not go with one of the quick shortcut methods. Reserve those for when you have a full understanding of it.

[RAM555789]

Just now, RAM555789 said:

Also to add on to what he said the numbers you match up with the binary is 128 64 32 16 8 4 2 1 so the bits turned "off" that are zero are you network, once I hit 256 I start to affect the third octate so 0.0.0.0 to 0.0.1.0 is 256 addresses, 0.0.2.0 to 0.0.0.0 is 512 address and so on.

After class I can put it on paper and pen but for first learning its best to do it the binary way he was talking about. The way the Army taught us already requires that basic understanding, its a steeping stone. This is also the basics of networking theres a lot more involved to hacking then just IP addresses.

[Leonard]

10 minutes ago, JoeyDM said:

Yeah I think I know the easier way. But I don't like it for teaching tbh, because it doesn't teach the why it works. It's important to know the 'Why', 'How', in addition to the 'What'.

 

Below is an easier way to do this within the fourth octet:

255.255.255.0

255.255.255.128

255.255.255.192

 

256-0 = 256 Addresses. -2 gives you your usable. 254 usable.

256-128 = 128 Addresses. -2 gives you your usable. 126 usable.

256 - 192 = 64 Addresses. -2 Gives you your usable. 62 usable.

 

This method is easy, but does not explain why, only the what... So I veer away from it for teaching.

What does 255.255.0.0 give you?

[Haeking]

11 minutes ago, JoeyDM said:

 

If you actually want to learn I would not go with one of the quick shortcut methods. Reserve those for when you have a full understanding of it.

No no of course I want to learn the whole feel of subnetting right now Im just doing a booklet that is this: http://www.cod.edu/people/faculty/chento/secure/lectures/xx-cit121/Ip Addressing and Subnetting Workbook - Instructors Version v2_0.pdf

[Haeking]

2 minutes ago, Leonard said:

What does 255.255.0.0 give you?

That's a class B address so it'd start with at least 128 if Im correct so a base would be like 128.16.0.0 or 128.0.0.0 on forth

[Unhelpful]

Just now, Leonard said:

What does 255.255.0.0 give you?

Well let's take a look at what 255.255.0.0 actually means:

8 Bit Value:

255 = 11111111

In order it's the following turned on: 128  64  32  16  8  4  2  1. The 8 bits represent each of those numbers, in that order. 

11111111 means that all 8 bits are turned on, so add them all up. 128+64+32+16+8+4+2+1=255. 0 is also a valid usable number, so it's a total of 256 addresses, not 255. So +1.

255.255.0.0 = 11111111.11111111.00000000.00000000.

 

255.255.255.0 gives you 256 total, and 255.255.0.0 gives you 256 blocks of 256 rolled up into 1, so 256*256=65536. You have 65534 total usable IP Addresses in a /16.

[Unhelpful]

39 minutes ago, Haeking said:

That's a class B address so it'd start with at least 128 if Im correct so a base would be like 128.16.0.0 or 128.0.0.0 on forth

Nope. Slight misunderstanding. Read my post above this one and check again.

 

Edit: You wouldn't be quite wrong from the traditional classful addressing, but classful is kinda dead, thanks to variable-length subnet masks (VLSM). CIDR = Classless Internet Domain Routing. An example of CIDR notation would be /25, meaning 25 bits turned on, or 128 addresses with 126 usable.

[RAM555789]

4 minutes ago, Leonard said:

What does 255.255.0.0 give you?

Well if that's a subnet mask then its a /16 network 

[Leonard]

2 minutes ago, RAM555789 said:

Well if that's a subnet mask then its a /16 network 

Do you know of encapsulating a network inside another to hide/encrypt the used subnet mask?

[RAM555789]

Just now, Leonard said:

Do you know of encapsulating a network inside another to hide/encrypt the used subnet mask?

Well they teach us a little about tunneling, but when it comes to encrypting the traffic, they just teach us the steps we go through to use a TACLANE encryption device.