Multicast address and their use:

224.0.0.1 ------------------> it used on a network all system on a subnet

224.0.0.2--------------------> all routers on a network

224.0.0.5---------------------> ospf link state advertisement

224.0.0.6----------------------> ospf DR used this address to update all routers LSDB.

224.0.0.9----------------------> Dynamic routing protocol RIP used this for an update.

224.0..10------------------------> EIGRP PROTOCOL USED IT.

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TCP/IP 3 way handshaking

on a client server architecture:-

client------request----------------->SYN or sequence no pkt-------------to Server
Server---------response------------SYN/ACK pckt -------------------------to client
clent-------------acknowledged-------------ACK pckt---------------------back to Server
Client/Server-------transfer begin-----------Connection established (i.e reliable)
Client-------client get all the data from server now want to finish--------FIN/ACK----------------------to Server.
Server-------ok i am closing ur connection------------------ACK-------------------to client


TCP protocol which HTTP, FTP, etc