Few basic Network Protocols IPV4 & 6 Telnet, UDP & TCP
Difference between IPV4 and IPV6
What Is Telnet?
Telnet is a simple, text-based network protocol that is used for accessing remote computers over TCP/IP networks like the Internet.
What are the Telnet Client & the Telnet Server?
1. Telnet Server — if you install this feature, you will be able to configure your Windows computer to run as a Telnet server. This means that your computer will listen for incoming connections and allow others to use it. If you’re not beneath a firewall and you have a public IP address, anyone in the world will be able to remote control your computer using a Telnet Client.
2. Telnet Client — this will enable you to connect through Telnet to any server of this type, using just a Command Prompt window.
What Are The Security Implications Of Using Telnet?
Even if Telnet was great when it was invented and it revolutionized the use of technology, it does have some flaws. The worst of them is that it is not secure! Telnet sends and receives data only in plaintext, without any kind of encryption. This means that whenever you connect to a Telnet server, your personal data like your username and password will be transmitted as clear text. Anyone who knows how to use an application for sniffing network connections, will see all the data being transmitted.
Basically, anyone trying to use Telnet for serious things like transferring valuable information or administering business servers, is just plain crazy.
What is UDP & TCP
UDP (User Datagram Protocol) is an alternative communications protocol to Transmission Control Protocol (TCP) used primarily for establishing low-latency and loss tolerating connections between applications on the Internet. Both UDP and TCP run on top of the Internet Protocol (IP) and are sometimes referred to as UDP/IP or TCP/IP. Both protocols send short packets of data, called datagrams.
TCP has emerged as the dominant protocol used for breaking large data sets into individual packets, checking for and resending lost packets and reassembling packets into the correct sequence. But these additional services come at a cost in terms of additional data overhead, and delays called latency.
In contrast, UDP just sends the packets, which means that it has much lower bandwidth overhead and latency. But packets can be lost or received out of order as a result, owing to the different paths individual packets traverse between sender and receiver.
For the realtime services like computer gaming, voice or video communication, live conferences; we need UDP. Since high performance is needed, UDP permits packets to be dropped instead of processing delayed packets. There is no error checking in UDP, so it also save bandwidth. In some cases, forward error correction techniques are used to improve audio and video quality in spite of some loss.
