Please enable JavaScript.

Coggle requires JavaScript to display documents.

MODULE 7: WAN CONCEPTS, image - Coggle Diagram

- - - - There are two systems used to define the digital capacity of a copper media serial link:
      - T-carrier - Used in North America, T-carrier provides T1 links supporting bandwidth up to 1.544 Mbps and T3 links supporting bandwidth up to 43.7 Mbps.
      - E-carrier - Used in Europe, E-carrier provides E1 links supporting bandwidth up to 2.048 Mbps and E3 links supporting bandwidth up to 34.368 Mbps.
- - - - Service providers now offer Ethernet WAN service using fiber-optic cabling. The Ethernet WAN service can go by many names, including the following:
      - Metropolitan Ethernet (Metro E)
      - Ethernet over MPLS (EoMPLS)
      - Virtual Private LAN Service (VPLS)
      - The figure displays a simple Metro Ethernet topology example.
- - - - Fiber to the Home (FTTH) - Fiber reaches the boundary of the residence. Passive optical networks and point-to-point Ethernet are architectures that can deliver cable TV, internet, and phone services over FTTH networks directly from an the service provider central office.
      - Fiber to the Building (FTTB) - Fiber reaches the boundary of the building, such as the basement in a multi-dwelling unit, with the final connection to the individual living space being made via alternative means, like curb or pole technologies.
      - Fiber to the Node/Neighborhood (FTTN) - Optical cabling reaches an optical node that converts optical signals to a format acceptable for twisted pair or coaxial cable to the premise.
  - - - ISPs still use PPP as the Layer 2 protocol for broadband DSL connections because of the following factors:
      - PPP can be used to authenticate the subscriber.
      - PPP can assign a public IPv4 address to the subscriber.
      - PPP provides link-quality management features.
      - A DSL modem has a DSL interface to connect to the DSL network, and an Ethernet interface to connect to the client device. However, Ethernet links do not natively support PPP.
  - - - Cost savings- VPNs enable organizations to use the global internet to connect remote offices, and to connect remote users to the main corporate site. This eliminates expensive, dedicated WAN links and modem banks.
      - Security- VPNs provide the highest level of security by using advanced encryption and authentication protocols that protect data from unauthorized access.
      - Scalability- Because VPNs use the internet infrastructure within ISPs and devices, it is easy to add new users. Corporations can add large amounts of capacity without adding significant infrastructure.
      - Compatibility with broadband technology- VPN technology is supported by broadband service providers such as DSL and cable. VPNs allow mobile workers and telecommuters to take advantage of their home high-speed internet service to access their corporate networks. Business-grade, high-speed broadband connections can also provide a cost-effective solution for connecting remote offices.
      - VPNs are commonly implemented as the following:
      - Site-to-site VPN - VPN settings are configured on routers. Clients are unaware that their data is being encrypted.
      - Remote Access - The user is aware and initiates remote access connection. For example, using HTTPS in a browser to connect to your bank. Alternatively, the user can run VPN client software on their host to connect to and authenticate with the destination device.