it

• Osi (Open systems interconnection- 7 layer

  Tcp (Transmission Control Protocol) - 4 layer
• All people seem to need data processing

  • App
  • Presentation
  • Session
  • Transport
  • Network
  • Data-link
  • Physical
• Tcp- Connection oriented, data is broken into segments and numbered
• Udp- used for audio and video
• UDP uses less overhead than TCP
• Data goes into

  • Segments
  • Packets
  • Frames
  • Bits
• what is the four layers of TCP

  • Application
  • transport
  • Internet
  • Network services
• Application layer- formatting data
• Transport layer- segments data
• Internet layer- data into packets
• Network access- breaks data into bits
• subnetting - act of splitting physical networks into logical subnetworks
• Ipconfig command by itself- it will display ip information for each network adapter
• ipv4 - ip address standard for decades used for configure
• Ipv6 address with ipv4 numbering at the end is called - ipv4 mapped address
• subnet mask for an ip address defines the network portion.
• main purpose of subnet mask- determine the size of the subnet within a network.
• Classes

  • A B C - represent ip address in wide use on networks
• class d- not assigned, used for multicast transmissions
• class e is used for research
• first 3 groups of ipv6 address represent - network address
• fourth group is the subnet address
• device address is last
• command to release - ipconfig/release

  to renew- ipconfig/renew
• why use ipv6- security and address space
• ipse provides- authentication and encrypt on data
• hexadecimal numbers range from 0-9 and A-F
• contiguous group of four zeros can be replaces with a double colon
• the first 3 options represent- the network
• fourth portion represent- the subnet
• global unicast starts with - 2 or 3
• unique local ipv6 starts with- FC or FD
• link starts with- FE80
• HTTP is the main protocol for- webpages
• domain name server (DNS) runs on - port 53

  main function- map host names to ip addresses

  using a records
• Remote Desktop protocol (RDP) runs on - port 3389

  used to connect one device to another remotely

  Secure shell (ssh) - used to connect a device to a hardware, such as a router

  SSH- encrypted, runs on - port 22
• DNS- host names to ip addresses.

  worldwide dns servers how many- 13

  command for dns- ipconfig/all
• A records- ipv4 records

  AAAA- ipv6 records
• Cname records- create aliases for host names

  MX records- indicate mail servers in a network
• MX AND CNAME- have to be entered manually