CCNA 1 - Finals Flashcards
: Responsible for end-to-end data exchange between devices.
Network Layer
: Core protocol of the network layer (IPv4 and IPv6).
IP (Internet Protocol)
: Wrapping data within IP headers by examining layer 3 (no impact on layer 4)
Encapsulation
: Determining the best path for data delivery.
Routing
: Removing IP headers.
De-encapsulation
: Maximum size of data that can be transmitted in a single frame.
MTU (Maximum Transmission Unit)
: Dividing large packets into smaller units. (layer 3)
Fragmentation
: Is the primary communication protocol for the network layer.
IPv4
The network header has many purposes:
- *It ensures the packet is sent in the correct direction (to the destination).
- *It contains information for network layer processing in various fields.
- *The information in the header is used by all layer 3 devices that handle the packet
: Translates private IP addresses to public ones.
NAT (Network Address Translation)
: Next-generation IP protocol with improved features and larger address space.
IPv6
: Contains information about network destinations and paths to reach them.
Routing Table
: The router that handles traffic destined for networks outside the local network.
Default Gateway
: Manually configured routes.
Static Routing
: Automatically discovers and maintains routing information.
Dynamic Routing
A host can send packets to the following:
- Itself – 127.0.0.1 (IPv4), ::1 (IPv6)
- Local Hosts – destination is on the same LAN
- Remote Hosts – devices are not on the same LAN
– Source uses its own IP address and Subnet mask, along with the destination IP address
IPv4
– Source uses the network address and prefix advertised by the local router
IPv6
is dumped out the host interface to be handled by an intermediary device.
Local traffic
is forwarded directly to the default gateway on the LAN.
Remote traffic
There three types of routes in a router’s routing table:
Directly Connected – These routes are automatically added by the router, provided the interface is active and has addressing.
Remote – These are the routes the router does not have a direct connection and may be learned:
* Manually – with a static route
* Dynamically – by using a routing protocol to have the routers share their information with each other
Default Route – this forwards all traffic to a specific direction when there is not a match in the routing table
MAC vs IP Address
- MAC Address: Unique physical address of a network interface card (NIC). Layer 2
- -Used for NIC to NIC communications on the same Ethernet network.
- IP Address: Logical address used to identify devices on a network. Layer 3
- -Used to send the packet from the source device to the destination device.
is used by IPv6 to associate the IPv6 address of a device with the MAC address of the device NIC.
ICMPv6
: Used by IPv4 to map IP addresses to MAC addresses.
ARP (Address Resolution Protocol)
The command displays the ARP table on a Cisco router.
show ip arp
The command displays the ARP table on a Windows 10 PC.
arp –a
: Attack where an attacker sends false ARP messages to redirect network traffic.
ARP Spoofing
: A network device that forwards data packets between different networks.
Router
: A point of connection between the router and the network.
Interface
: The router interface that handles traffic destined for networks outside the local network.
-used when a host sends a packet to a device on another network.
Default Gateway
used to store the router’s configuration.
NVRAM: Non-Volatile Random Access Memory
: Contains information about network destinations and the paths to reach them.
IP Routing Table
Description, no shutdown, show ip int brief, show ip route, show int, show ip int
description command: add infos about the network connedted to the interface
No shutdown command: activates the interface
Show ip int brief (ip/ipv6): displays all interfaces, their IP addresses, and their current status.
Show ip route: displays the contents of the IP routing tables stored in RAM
Show interface: displays statistics for all interfaces on the device. Only displays the IPv6 addressing infos.
Show ip interface: displays the IPv4 statistics for all interfaces on a router
: A 32-bit address used to identify devices on an IP network.
IPv4 Address
: Determines the network and host portions of an IPv4 address.
Subnet Mask
: A concise way to represent the subnet mask.
Prefix Length
: Transmission to a single destination IP address.
Unicast
: Transmission to all devices on a network.
Broadcast
: Transmission to a specific group of devices.
Multicast
: Globally routable address assigned by an ISP.
Public IP Address
: Non-routable address used within a private network.
-are common blocks of addresses used by most organizations to assign IPv4 addresses to internal hosts
-are not unique and can be used internally within any network.
Private IP Address
: Translates private IP addresses to public ones.
NAT (Network Address Translation)
: 127.0.0.1, used for testing local TCP/IP connectivity.
Loopback Address
:0 Self-assigned address used when DHCP is unavailable.
Link-Local Address
: A network segment where broadcast traffic is propagated.
Broadcast Domain