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Protocols:
-Set of rules
-Defines what type of communication
-different protocols use for different types of communication
Protocols Port No
HTTP 80 --Website
HTTPS 443 -- HTTP OVER SSL - HTTP SECURE - ENCRYPTION
FTP 20,21 -file upload and download
SSH 22 -Remote Access-CLI-Encrypt
TELNEL 23 -Remote Access - CLI
RDP 3389 -Remote Desktop - GUI - Windows
SMTP 25 -to send mails
POP3 110 -receive/retrieve mails
IMAPv4 143 -receive/retrieve mails
TFTP 69 -remote configuration upload/backup
DHCP 67,68 -DHCP Server Assign/configure ip address to client device
DNS 53 -name resolution, name to ip addr
Kerberos 88 -Authentication and Authorization -Windows - Active Directory
LDAP 389 -Authentication and Authorization -Win and Linux/Unix
SNMP 161,162 -Monitoring - Device status and Details
NTP 123 -Time synchronization - time.windows.com
MySQL Server - Database -- 3306
Oracle DB Server -TNS Listener- 1521
Tomcat -Web Application Server -- 8080
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OSI Model:
-Open System Interconnect
-Network Model
-Reference Model
-Understand, Troubleshooting, Maintaining, Creating Network
-7 layer model
-Standardized by ISO (International Organization for Standardization)
7-Application
6-Presentation -Software layer
5-Session
4-Transport -Heart of OSI, End to End connection, Error Correction
3-Network -Router -
2-Data Link -Switch -Hardware Layer
1-Physical -HUB -
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7-Application -Data Server or Client Side App, Ex. Web Browser, Outlook, MS IIS, MS Exchange
-Protocols
6-Presentation -Data Encode and Decode - Convert Data in different format ex. pdf,doc,png, jpg, mp3, mp4 .., into ASCII
Compression and Decompression - Compress the Data to reduce size
Encryption and Decryption - encrypt the data to secure the data
5-Session -Data Create session- session id, maintain, terminate Authentication and Authorization
4-Transport -Segment Segment the data, Numbering and Sequencing, TCP and UDP Portno added, Windowing/flow control-no of segment are sent, Error Correction
TCP Header + Segmented Data = Segment
3-Network -Packet Routed Protocols - Logical Address - IP Address
Add - Source IP Address and Destination IP Address
Routing Protocols - RIP, EIGRP, OSPF,
Add - Routing information -- Path to reach Destination
Nw Header
SIP + DIP + Segment = Packet
2-Data Link -Frame LLC - Logical Link Control
- WAN Protocols - PPP, PPPoE, GPON, Frame Relay, DSL/ADSL,MPLS, SD-WAN
MAC - Media Access Control - MAC Address is called Physical Address
CRC -Cyclic Redundancy Check - generate a checksum data - error detect
Data Header Data Tail
Smac + Dmac + Packet + CRC = Frame
1-Physical -Bit Steam Frame is converted into Bit Stream
Physical connectivity - Wired type or Wireless type
Based Connection it converts Bit Steam into that related Signal
Ethernet NIC - UTP/STP Cable -- Electrical Signal
HBA NIC - Fiber Optical cables -- Lightwave
Wi-Fi NIC - Wi-Fi bands 2.4GHz and 5GHz - Radio signal
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TCP UDP
Transmission Control Protocol User Datagram Protocol
*the protocols are can be TCP type or UDP type or Both
Ex. Http, Https, FTP, SMTP, DNS Ex. TFTP, DHCP, DNS
Reliable Non - Reliable
Connection Oriented Connection Less
Acknowledgement Based No Ack
Slower than UDP due to Ack Faster than TCP, due to no Ack
S ---- D S D
1 ---- 1 1 ---- 1
-ack1- 2 ---- 2
2 ---- 2 3 ----
-ack2- 4 ---- 4
3 ---- x 5 ---- 5
.... 6 ---- 6
4 ---- 4 7 ---- 7
-ack4- 8 ---- 8
3 ---- 3
-ack3-
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TCP/IP Protocol Suite
-Transmission Control Protocol/Internet Protocol
-DoD Model -- Department of Defense
-4 Layers
Application -Application, Presentation, Session
Transport -Transport
Internet -Network
Network Access -Datalink , Physical
NIC Card -- Network Access layer
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*We are using
-TCP/IP Model
-UTP/STP Cable
-STAR Topology
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