Brochure

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Ethernet Basics

Ethernet is a widely used communications protocol that is used to transmit data packets (datagrams) between network devices. Imagine a

highway in a large metropolitan area six lanes wide at rush hour. The vehicles on the highway need rules to follow so that they get to their

destination without crashing into each other. In an Ethernet network link, there could be 100 million bits of information transmitted in one

second. In the Ethernet standard, there exist rules to govern packet structure, transmission requirements, error correction, communication

with end equipment, etc.

Examining the differences between 100Mhz, 100 Base TX, Cat5e; what does it all mean?

When discussing connectors and Ethernet, there are a few key details to be aware of:

• 100Mhz is a measurement of Frequency for the signal

- Comparable to the Speed Limit of a highway

• 100BaseTX (or Fast Ethernet) is an Ethernet link standard and identiﬁ es available link bandwidth The bandwidth is measured in units of

MBits/S (megabits per second)

- Comparable to the number of cars that pass a point in one second

• Cat5e is an EIA/TIA standard for performance and physical characteristics for cables and connectors

- Comparable to performance speciﬁ cations of the car and highway

In connectors and cables, Fast Ethernet uses 2 pairs, one for transmit, one for receive. This, way data trafﬁ c can ﬂ ow in both directions

simultaneously.

In order to explain basic Ethernet theory, we can use a functional comparison to a busy city with highways, buildings, and cars. To illustrate

this, the table below provides correlation between the different components/pieces/links that encompass Ethernet network connectivity, and

the larger scale infrastructure of a metropolitan city.

• City: The network itself

• Buildings: End equipment, PC, server, etc.

• Roads: Ethernet cabling

• Cars: Data packets, datagrams, bits, bytes, etc.

• Tolls: Firewalls

• Bridges: Connectors

• Trafﬁ c laws: Protocol/communication speciﬁ cations

UTS Series

Technical information

Ethernet for the layman

Technical information