CCNA - Capitulo 8.4

CCNA - Capitulo 8.4

1. INTERNET LAYER

   • HOST FORWARDING DECISION
     • A HOST CAN SEND A PACKET TO THE FOLLOWING
       • LOCALHOST ITSELF
         • IPV4 :127.0.0.1
         • IPV6 ::/1
         • TESTS THE TCP/IP PROTOCOL STACK ON THE HOST.
       • LOCAL HOST
         • SOURCE E DESTINATION HOST
           • SAME NETWORK
         • IF THE DESTINATION IS LOCAL, IT DOESN'T GO THROUGH THE ROUTER.
       • REMOTE HOST
         • SOURCE & DESTINATION
           • DOES NOT NOT THE SAME NETWORK
       • WHO DETERMINES IF THE DESTINATION IS IN THE SAME NETWORK? IT'S THE ORIGIN.
         • HOW DOES IT DO THAT? IPV4
           • SOURCE COMPARE
             • 1 ) ITSELF MASK
             • 2) DESTINATION IPV4
             • 3- ITSELF ADDRESS IPV4
         • HOW DOES IT DO THAT? IPV6
           • LOCAL ROUTER ADVERSISES PREFIX
             • ALL DEVICES ON THE NETWORK
     • DEFAULT GATEWAY
       • DOORWAY
       • DHCPv4
         • GATEWAY , DNS
       • IPV6
         • THE ROUTER ADVERTISES (LLA)
       • CHARACTERITICS GATEWAY
         • IT HAS A LOCAL IP ADDRESS IN THE SAME ADDRESS RANGE
           • BEST PRACTICES
             • 254
             • 1
         • ACCEPTA DATA INTO THE LOCAL AND FORWARD OUT THE LOCAL
         • IT ROUTES TRAFFIC OTHER NETWORKS
         • IP OF THE ROUTER ON THE LOCAL NETWORK
       • NOTE: THE ROUTER ALWAYS CHOOSES THE MOST SPECIFIC ROUTE TO A DESTINATION, FOR EXAMPLE:
         • 3º ESCOLHA 0.0.0.0 0.0.0.0/0
         • 1 º DESTINO : 192.168.1.8 255.255.255.255/32
         • 2 º ESCOLHA 192.168.1.8 255.255.255.248
         • NETWORK 192.168.1.0/29
       • WHO COULD BE THE GATEWAY ?
         • ROUTER , SWITCH LAYER 3 , FIREWALL
     • HOST ROUTE TO THE DEFAULT GATEWAY
       • HOST ROUTING TABLE
       • FORWARDING ROUTER
         • THE BEST (LONGEST) MATCHING ROUTE ENTRY (HIGH MASK)
       • HOST ROUTING TYPICALLY INCLUDE A DEFAULT GATEWAY
         • HOW VIEW ?
           • ROUTE PRINT OR NETSTAT - R
             • 1 - INTERFACE LIST
               • MAC
               • ADAPTERS
             • 2 - IPV4 ROUTE TABLE
               • DIRECT CONNECTIONS
               • LOCAL NETWORK
               • DEFAULT ROUTES
             • 3- IPV6 ROUTE TABLE
               • DIRECT CONNECTIONS
               • DEFAULT ROTES
               • LOCAL NETWORK
       • HAVING A DEFAULT GATEWAY CREATES A DEFAULT ROUTE
         • ROUTING TABLE OF THE PC
           • DEFAULT ROUTE IS THE ROUTE PATHWAY COMPUTER CONTACT A REMOTE NETOWORK , WHEN THERE IS NO MORE SPECIFIC ROUTE
             • EXCEPTION ?
               • IF THERE IS A MORE SPECIFIC ROUTE ON THE HOST
                 • 54.48.545.05 WILL BE CHOSEN OVER 0.0.0.0/0
       • WHEN A HOST SENDS A PACKET TO ANOTHER HOST
         • IT CONSULTS ITS ROUTING TABLE TO DETERMINE WHRRE SEND PACKET
           • DESTINATION REMOTE ?
             • FORWARDED DEFAUT GATEWAY
               • WHAT HAPPENS WHEN A PACKET ARRIVES ROUTER INTERFACE ?
           • LOCAL ROUTER
             • SEND DIRECTLY
     • MAXIMUM TRANSMIT UNIT (MTU)
       • IS PASSED TO THE NETWORK LAYER BY THE DATA LINK LAYER
     • IPV4 AND IPV6 PACKET ALWAYS CREATE SOURCE HOST ?
       • END DEVICES CREATE THEIR OWN ROUTING TABLE

Images and files in the map