All About IP Addresses

Lately I have been bingeing videos on Youtube about network basics such as network hardware like  hubs, switches, and routers as well as on the software protocols like IP addresses, OSI, TCP, NAT, ARP, and particularly DHCP (Dynamic Host Configuration Protocol).  We use them daily since we are mostly on our smartphones but generally oblivious and don't care much on how they work.

Simply put devices on a network whether home network, office network, or internet(work) need IP addresses to communicate via IP or Internet Protocol.  Home routers generally have a DHCP server built into them that automatically generates IP addresses for network devices such as laptops and mobile devices that tries to connect to the network. 

Just recently I learned about the concept of Public versus Private IP Addresses. Yeah, most of us wouldn't care much about the nitty-gritty of technology.  All we care about is when we open our laptop, smartphone, or Smart TV our home router will connect us to the internet to get our Facebook feeds, video streams from YouTube or our daily binge on Netflix or Disney+. Our focus is just mostly on whether the internet is up or down.

For most of us all the IP addresses in our home network are Private IP Addresses and they are basically not unique and are repeated and reused in other home networks as well.  

What is unique is the Public IP Address that is assigned by the ISP Provider which you can discover under "what is my ip" via Google search or some other online IP Lookup sites such as https://whatismyipaddress.com/

Your private IP address exists within specific private IP address ranges reserved by the Internet Assigned Numbers Authority (IANA) and should never appear on the internet. There are millions of private networks across the globe, all of which include devices assigned private IP addresses within these ranges:

• Class A:       10.0.0.0 —   10.255.255.255
• Class B:   172.16.0.0 —   172.31.255.255 
• Class C: 192.168.0.0 — 192.168.255.255 

Class C is where home networks generally fall.  Hence to access your router configuration you would most likely go to 192.168.1.1 though other router manufacturers put it somewhere else but still within 192.168.x.x.

 I tried doing an IP Lookup of the usual router IP address such as 192.168.1.1 and here is the result

The IP address has been classified as a Bogon IP Address which means it doesn't belong to a specific user or server on the internet and as such should not appear on the public internet. The term bogon is used as slang and is derived from the word bogus though there is nothing bogus about the huge chunk of Special-Use IPv4 Addresses (RFC 3330) as allocated by the Internet Assigned Numbers Authority (IANA). 

Bogon IP Address Ranges

• Private IP Addresses.  As mentioned above the following IP address ranges have been reserved by the Internet Assigned Numbers Authority (IANA) for use for Private Networks

• Class A:       10.0.0.0  —   10.255.255.255
• Class B:   172.16.0.0  —   172.31.255.255
• Class C: 192.168.0.0  — 192.168.255.255 

• Automatic Private IP Addressing (APIPA).  If a network client fails to get an IP address using DHCP, it can discover an address on its own using APIPA.

• 169.254.1.0  — 169.254.254.255

• To get an IPv4 address, the client will select an address at random in the range with a netmask of 255.255.0.0. The client will then send an ARP packet asking for the MAC address that corresponds to the randomly-generated IPv4 address. If any other machine is using that address, the client will generate another random address and try again.

• Special-Use IPv4 Addresses
• https://www.ietf.org/rfc/rfc3330.txt 

• Bogons arise as a result of a misconfiguration or intentional misuse that fools recipients about its source IP address. 
• Some IP addresses and IP ranges are reserved for special use, such as for local or private networks,  These reserved ranges, along with other IP ranges that haven't yet been allocated 
• and therefore also shouldn't appear on the public internet are sometimes known as bogons.

Because bogon IP addresses 

Today I learned about a nifty network tool called Wireshark that sniffs transmission packets on your network.  I haven't really studied much about the many features of the utility but just curious about the traffic going on in my router.

 so there's no way to geolocate them. Therefore our IP geolocation API won't return location information for IP addresses within bogon ranges, but it will return a bogon field to indicate that the IP address is a bogon.

IETF

https://www.ietf.org/rfc/rfc3330.txt

https://www.techtarget.com/searchnetworking/definition/bogon

https://www.techtarget.com/searchnetworking/definition/bogon#:~:text=A%20bogon%20is%20an%20illegitimate,Assigned%20Number%20Authority%20(IANA).

https://stevessmarthomeguide.com/internal-external-ip-addresses/#:~:text=What%20Is%20an%20External%20IP,typically%20have%20two%20network%20interfaces.

https://superuser.com/questions/1441998/is-my-routers-ip-address-really-public#:~:text=Yes%2C%20your%20IP%20is%20public,and%20it%20almost%20never%20changes.

https://en.wikipedia.org/wiki/Private_network

https://phoenixnap.com/kb/public-vs-private-ip-address