Section 9 : TCP/IP application

1. Telnet and SSH

1.1. telnet enables you to access a remote computer

1.2. - Telnet runs on TCP port 23

1.3. - Telnet it was the original remote connectivity tool and it’s arguably the oldest application there is on the internet

1.4. - SSH is fully encrypted and has almost completely replaced telnet

2. 51. Introduction to wireshark

2.1. - wireshark is a protocol analyzer and its making decisions and determine what’s going on in the systems

2.2. - Wireshark is a free third party tool

3. 52. Introduction to netstat

3.1. - netstat its a text based command that allows you to see what connection are established between your computer and other computers at any given moment

3.2. - The netstat command lists all open ports network connection on your computer

3.3. Netstat : O shows the executable and process ID for every connection

4. Web server

4.1. - web servers host web sites : web client access web servers

4.2. - HTTP uses TCP port 80 by default

4.3. - HTTPS uses TCP port 443 by default

5. 55. E-mail servers and clients

5.1. - TCP port 25 : referred to simple mail transfer protocol , during receive e mail you’ve two choices:

5.1.1. - 1- post office protocol version 3 uses port 110

5.1.2. - 2- Internet messages access protocol version 4 uses port 143

6. introduction to TCP and UDP

6.1. - iTCP segments act like servers and clients

6.2. - TCP is a connection oriented protocol that means it’s going to create a connection between two different computers and it’s going to make good and sure that data gets to the other machine in good order and complete

6.3. - UDP is a connectionless protocol and can Actually be better than TCB because it’s fast and low overhead

7. 50. ICMP AND IGMP

7.1. ICAMP works at the IP layer of OSI model

7.2. - Ping and ARP are ICMP applications

7.3. - IGMP stands for internet group management protocol

7.4. - IGMP is work as A packet that contains Type A checksum and group address and a source address

8. FTP

8.1. - FTP referred to file transfer protocol

8.2. - FTP uses port 21 and 20

8.3. - FTP is great place for doing really basic like file downloads