Programming4Interviews

  What is TACACS and how does it differ from RADIUS? TACACS is mainly used to authentication,authorization and accounting of entire process whereas Radius server uses AAA only to encrypt password and doesn't encrypt or monitor the whole process. TACACs is cisco proprietary and uses port 49 whereas Radius is IETF standard used globally and uses port 1812 and 1813. Radius server combines both Authentication and Authorization and gives minimum or only login accouting part whereas Tacacs checks for user authentication and priviledges allowed during authorization step and accounts each and every step/command from login to logout of the user. TACACS+ is used for authentication, authorization, and accounting (AAA) of the entire process. TACACS+ is Cisco proprietary and uses port 49, while RADIUS is an IETF standard using ports 1812 and 1813. TACACS+ separates authentication and authorization, whereas RADIUS combines them. TACACS+ encrypts the entire packet, providing enhanced security, ...

  End-to-End Networking Flow Step Description Configuration Example 1 User A initiates communication : User A sends a data packet from their device. N/A 2 Data packet reaches Switch A : The packet is sent to the local switch (Switch A) connected to User A. interface GigabitEthernet0/1 switchport mode access switchport access vlan 10 3 Switch A processes the packet : Switch A checks its MAC address table to determine the destination port. show mac address-table 4 Switch A forwards the packet : The packet is forwarded to the router (Router A) connected to Switch A. interface GigabitEthernet0/2 switchport mode trunk 5 Router A receives the packet : Router A examines the packet's destination IP address. interface GigabitEthernet0/0 ip address 192.168.1.1 255.255.255.0 6 Router A routes the packet : Router A uses its routing table to determine the best path to the destination network. show ip route 7 Packet traverses the network : The packet is forwarded through intermediate routers tow...

  Networking Questions: Explain the differences between TCP and UDP. In what scenarios would you use each? Here's a comparison between TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) in tabular format: Feature TCP UDP Connection Connection-oriented Connectionless Reliability Reliable, ensures data delivery Unreliable, no guarantee of data delivery Error Checking Extensive error checking and recovery Minimal error checking Flow Control Yes, manages data flow to prevent congestion No flow control Speed Slower due to overhead Faster, less overhead Data Transmission Ordered and retransmitted if lost No ordering, no retransmission Use Cases Web browsing, email, file transfer Streaming, gaming, VoIP Header Size Larger header (20 bytes) Smaller header (8 bytes) Congestion Control Yes, adjusts transmission rate No congestion control Scenarios for Use: TCP  is ideal for applications where reliability and data integrity are crucial, such as: Web browsing Email File ...