Please enable JavaScript.

Coggle requires JavaScript to display documents.

CCNA - Coggle Diagram

- - - - NAT with private Addressing was implemented to extend the life of IPv4 while the internet migrates to IPv6
- - - - Flow control is the handling of flow from sender so the host can handle it.
    - - The process of handling multiple session at once, and managing the streams over a single link.
    - - The source port in a TCP/UDP header is also used with the destination port number to track the sessions
    - - TCP uses a three way handshake to establish a session, it starts with the sender sending a SYN request, a SYN_ACK is then sent by the host followed by an ACK by the sender, this is the three way handshake complete.
        
        The TCP header
        
        starts with source an destination ports, followed by a sequence number and an acknowledgement number for authorization. After these is the header length, reserved and code bits and then the window. A checksum and Urgent specification are then added and Options for the TCP packet and finally the data.
    - - Sends through best effort, no handshake and no connection orientation. Its not reliable and does not perform flow control. It is much quicker than TCP however.
        
        The UDP header is much smaller than the TCP header and consists of the source and destination port, followed by the length and checksum, and then lastly the data.
  - - - Consists of version spec, and a header length, the type of service and the total length of the message. the ID and the flag followed by an offset. After which it specifies the TTL, the protocol and the checksum. It then has the source an destination IP address followed by options and finally data.
    - - Unicast
        
        Performs communications to a single destination host
      - Broadcast
        
        Performs a communication to all hosts on the subnet the client is located on.
      - Multicast
        
        Sends packets to multiple interested hosts (Streaming)
        
        Old multicast sent a separate copy of the traffic to each interested host which is technically unicast. Now a client sends one copy which is duplicated to all interested hosts on the router and switch.
    - - Addresses are in range 0.0.0.0 to 255.255.255.255, Network and Host address portions are specified by a subnet mask.
      - IP classes
        
        Class A
        
        These are addresses with a /8 subnet mask. (1-126)
        
        Class B
        
        These have a /16 subnet mask with first octet range 128 to 191
        
        Class C
        
        /24 subnet mask with first octet range 192 to 223
        
        Class D
        
        224 to 239 in the first octet are used for multicasting
        
        Class E
        
        240 to 255 in the first octet, these are used for research and experimental purposes.
        
        Private addressing
        
        For NAT Class A has 10.0.0.0/8, Class B has 172.16.0.0/16 and Class C has 192.168.0.0/24. Not routable on a public network
  - - - Coaxial
      - Copper UTP (Unshielded Twisted Pair)
        
        Ranges from Cat 3 - Cat 8.2 (including Cat 6A and Cat 7A)
        
        Straight through
        
        These cables let data flow in strictly one direction, mostly for router or switch connections
        
        Crossover
        
        These cables are used to connect two devices together directly
      - Twisted copper pair
      - fibre
        
        Long distance and high bandwidth
      - wireless
      - Connectors
        
        Mostly RJ-45
        
        Can get power over ethernet (PoE) which is good for powering things in strange areas like IP phones
- - - - The layer at which the actual data in a message is created and sent forward or received for reading by the user. Procedures for error recovery and data integrity are implemented on this layer.
    - - Provides standardized packet formatting for translating using a common format, across multiple data types.
    - - Provides a stream for continuous streamed messages between devices in full and half duplex. Synchronizes dialog between clients.
        
        Full duplex
        
        Communication is capable of going in both directions and both times
        
        Half Duplex
        
        Communication can only go in one direction at a time
    - - Transport protocol layer (TCP/UDP and ports specification)
    - - Routers and other IP comms. Logical addressing.
    - - Ethernet frames. MAC addressing
    - - Physical hardware
  - - - Application layer
        
        Summarizes the application, presentation and session layers of the OSI model. These are considered the upper layers in the stack and are handled by application developers.
      - Transport layer
        
        Works exactly the same as the transport layer in OSI
      - Internet layer
        
        Synonymous with the network layer in the OSI model (Layer 3)
      - Network Access layer
        
        Made up of both the physical and data-link layers in the OSI model.