Previous Page | Next Page

  1. Introduction
  2. Network Model
  3. Topology
  4. Physical Media
  5. Wireless Media
  6. Network Card
  7. Modems
  8. Outside Connections
  9. Wide Area Network Connections
  10. Repeaters, Bridges, Routers
  11. Network Types
  12. Ethernet
  13. Token Ring
  14. ARCnet
  15. AppleTalk
  16. FDDI
  17. Architecture Comparisons
  18. Categories
  19. TCP/IP
  20. IPX/SPX
  21. NetBEUI
  22. AppleTalk
  23. SNA
  24. Others
  25. Suites and Network Layers
  26. Installing Drivers
  27. DNS
  28. Network Operating Systems
  29. Applications, mail, groupware, DBMS
  30. Backing up the network
  31. Troubleshooting
  32. Web, SNMP, admin, firewalls
  33. Networking Terms and Definitions
  34. Credits

Connections to a Network from Outside

Three options for connecting over a telephone service:

  • Dial-up connections.
  • Integrated Services Digital Network(ISDN) - A method of sending voice and data information on a digital phone line. Two 64Kbps B-channels with one 16Kbps D channel is provided with basic ISDN service. The D-channel is used tor call control and setup. Basic ISDN can provide 128Kbps speed capability. 23 B-channels and one D channel is provided with Primary ISDN.
  • Leased Lines - This involves the leasing of a permanent telephone line between two locations.

Remote Communication Protocols

  • Serial Line Internet Protocol (SLIP) - Allows computers to connect to the internet with a modem. No error checking or data compression. Only supports TCP/IP.
  • Point to Point Protocol (PPP) - Provides error checking and data compression. Also supports multiple network protocols such IPX/SPX and NetBEUI in addition to TCP/IP. Supports dynamic allocation of IP addresses.

Remote Access Service

Remote Access Service (RAS) with Windows NT allows users connecting to the network using a modem to use network resources. The NT RAS server can handle 256 connections. Windows NT RAS servers provide the following security features:

  1. User account security
  2. Encryption between the DUN (dial up networking) client and the server
  3. Callback capability

The client software is called Dial up networking (DUN) in windows NT4 and Windows95. For NT 3.51 and Windows 3.1 it is called a RAS client. These clients may be used to connect to the internet through an internet service provider (ISP).