Introduction to Data Communications
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On any 1 cable segment, the maximum allowed number of nodes is 30.

Minimum Distance between Nodes

Minimum distance between nodes is 0.6 m or 2 feet.

Velocity of propagation

The speed of the signal through the 10Base2 cable is 0.65c. ("c" is equal to the speed of light - 300,000,000 m/sec). The minimum velocity of propagation for 10Base2 specification cable is equal to 0.65 x 300,000,000 m/sec. This is determined by cable capacitance.

Maximum coaxial cable segment length 185 m.

The maximum segment length is 185 m (600 ft.) or a maximum 0.949 uSec propagation delay. Propagation delay not distance is what actually determines the maximum length of the segment. Propagation delay (units are seconds) is calculated by:

What is the propagation delay for a 185 m length of 10Base2 cable?

Maximum Number of Segments

Maximum of 5 segments (with 4 repeaters) can be along the path between any 2 network nodes: 3 may be coax segments having a maximum delay of 0.949 uSec and 2 may be link segments having a maximum delay of 0.949 uSec.

With no link segments used 3 populated coax segments can exist on a path.

Maximum Transfer Rate

The Maximum Data Transfer Rate for IEEE 802.3a is 10 Mbps (10,000,000 bits per second of data). In actual fact, data transfer is dependant on how many users are fighting for the bus and how fast the user's data can get on the bus.

Physical Bus/Logical Bus

IEEE 802.3a is a Physical Bus - the cable is physically laid out as 1 long cable with the network nodes attached to it.

It is also treated as a Logical Bus - electronically and logically it appears as 1 long cable with the network nodes attached to it.

Introduction to Data Communications
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