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  1. Introduction
  2. Network Topology
  3. Hardware Connections
  4. TCP/IP Ports and Addresses
  5. Network Protocol Levels
  6. Data Link Layer and IEEE
  7. Network Protocol Categories
  8. Repeaters, Bridges, Routers
  9. ARP and RARP Address Translation
  10. Basic Addressing
  11. IP (Network)
  12. TCP (Transport)
  13. UDP (Transport)
  14. ICMP
  15. Hardware Cabling
  16. Wireless media
  17. Outside Connections
  18. Ethernet
  19. Token Ring
  20. ARCnet
  21. AppleTalk
  22. FDDI
  23. IPX/SPX
  24. NetBEUI
  25. AppleTalk
  26. SNA
  27. Others
  28. Simple Routing
  29. More Complex Routing
  30. IP Masquerading
  31. Firewalls
  32. Domain Name Service (DNS)
  33. Virtual Private Networking
  34. DHCP
  35. BOOTP
  36. RPC and NFS
  37. Broadcasting and Multicasting
  38. IGMP
  39. Dynamic Routing Protocols
  40. Simple Mail Transfer Protocol (SMTP)
  41. Simple Network Management Protocol
  42. Network Services
  43. Installing Drivers
  44. Network Operating Systems
  45. Applications
  46. Wide Area Networks
  47. Backing up the network
  48. Fault Tolerance
  49. Troubleshooting
  50. Commonly used Network Ports
  51. Networking Terms and Definitions
  52. Networking RFCs and Protocols
  53. Further Reading
  54. Credits

ARCnet Network

ARCnet (Attached Resource Computer Network) (CR)

Topology is star and bus or a mixture. Cable type is RG-62 A/U coaxial (93 ohm), UTP or fiber-optic. A network can use any combination of this media. Connectors used include BNC, RJ-45, and others. It passes tokens passing for media access. Maximum segment length is 600 meters with RG-62 A/U, 121 meters with UTP, 3485 meters with fiber-optic, and 30 meters from a passive hub. The specification is ANSI 878.1. It can have up to 255 nodes per network. The speed is 2.5 Mbps. ARCnet Plus has operating speeds approaching 20Mbps.

Signals are broadcast across the entire network with computers processing only signals addressed to them. ARCnet tokens travel based on a station identifier (SID) which each computer has. Each network card has a DIP switch used to set the SID with an address between 1 and 255. Signals are generally sent from the lowest numbered station to the next until they wrap around back to SID of 1. To determine non-existent stations, the station with the lowest ID indicates it has the token and begins querying IDs of higher value until it gets a response. Then the next computer does the same until the original station is queried. This procedure is done when a station is added or removed from the network or when the network is originally started. How does the network know when a station has been added or removed? How is the lowest numbered SID identified? Addresses assignment is based on proximity, which helps the network operate more efficiently.

The acronym SID is used for a station identifier with regard to ARCnet, but as used in the Windows NT and Windows 95 operating systems, it refers to the security identification number of a user or group.