The OSI (Open System Interconnect) Model was developed in 1984 as an open standard to promote network interconnection and interoperability.

Layer Function Examples
7. Application End User : Support for applications HTTP, FTP, SMTP (email)
6. Presentation Syntax : Protocol conversion, structures data for the application ASCII, JPEG, etc.
5. Session Sync & Ports : Establishes, manages and terminates sessions & connections NFS, SQL
4. Transport End to End Connection : Is concerned with message integrity between source and destination TCP, UDP
3. Network Packets : Combines messages into packets, adding routing information IP, IPX
2. Data Link Frames : Handles flow control, sequencing, errors MAC
1. Physical Cables : Provides electrical and mechanical connections to the network cables and NIC

Written in hexadecimal notation, composed of 12 digits, the first 6 correspond to the Organizational Uinque Identifier (OUI) and the last 6 are given by the manufacturer to each device. Every MAC address should be unique.

Large manufacturers may have many several OUI.

  • DOS : Disk Operating System
    • The ancestor to Windows.
  • HAL : Hardware Absraction Layer
    • Used in virtualization technology.
  • MAC : Media Access Control
    • Unique identifier for any network device. See here.
  • NAT : Network Address Translation
    • Allows the translation of multiple local private addresses into a single public IP. Used in most home routers. More info
  • NTFS : New Technology File System
    • A file system used by Windows.
  • OUI : Organizational Unique Identifier
    • First part of the MAC address used to identify the manufacturer.
  • SSID : Service Set Identifier
    • Name used to identify it wireless networks from one another.
  • WAN : Wide Area Network
    • Large network not tied to a single location but spread across several locations. More info
  • Define kernels
  • Expand upond Topology (architectures)
  • List IANA somewhere (assigns IP addresses to the network and ensures their unicity)
  • Expand upon private IP addresses reserved (p. 50)
  • Talk about firewalls and Stateful Packet Inspection
  • Detail WAN/MAN/LAN
  • Detail NIC & MAC
  • Expand protocol / topology / deterministic
  • Compare hub vs switches
  • Ethernet Frame
  • Class of IP addresses
  • wired vs wireless (cite 3 advantages of each)
  • network/start.txt
  • Last modified: 2022/07/18 10:39
  • by mh