Internet is Mesh topology. read more to understand 😉
Star topology is singe point of failure, which mean all the devices are connected to hub connected as the center of star with single wire. If hub / switch fails network will go down.
Our home wifi works on wireless star topology, where in all cellphone/devices are connected to router as center of star.
In Mesh topology, one devices is connected with several other devices using multiple wires. (wire mesh). That way if one hub fails, network still works.
Mesh topology is opposite of single point of failure and is redundant, which means even if one router fails, data packet can be relayed or routed using different route or path. Imagine a big house with one in modem and router with multiple wifi extenders, that way if range is week for one extenders, data can still travel using other extender device to reach to modem 🙂
In computing, a denial-of-service attack is a cyber-attack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host connected to the Internet.
You can spin up thousands cloud servers for 2 hours and attach a server from several sources at specific time. Spot instance from AWS would be cheap. Since attack will come from different ips the target server will not be able to stop it easily.
Use different cloud providers, use different regions but start running the army of computer at the same time.
Mac address is the unique unchangeable address give to each network address. Technically mac address the real address, ip address is temprary, as you change your address your ip address will change but not your mac address ( when you use airport free wifi your ip is difference)
This is strange but true that all the devices in you home have same public ip address 😉 and that is the public ip of your router provided dynamically by your ISP.
ARP is Address resolution protocol which would help to resolve the public + private ip into a mac address. This get cached as well, so that whenever the communication happens the sender targets it towards mac address
In my house my router has been assigned dynamically a public ip, all my devices in home have a private ip address. Think of it as phone number for a company with phone extension for each employee. Hence it is responsibility of NAT ( acts like telephone receptionist) to translate private + public ip and establish the connection.
with ipv6, we do not need NAT any more 😉 since ipv4 are only 4 billion hows ipv6 which is 128 bits has delizzions ( more then billion, zillion etc) ip range available. But who knows we might even exhaust that too in future 😉
A firewall is a system that is designed to prevent unauthorized
access from entering a private network by filtering the
information that comes in from the internet. A firewall blocks
unwanted traffic and permits wanted traffic.