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How LAN works in video games if only one station is permitted to transmit?

Only one device is allowed to transmit at any given time. At any other given time, another device is allowed to transmit. How can you have a conversation at a dinner table if only person can speak at ...
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18 votes

How LAN works in video games if only one station is permitted to transmit?

Some LAN protocols, on some media, are half duplex. That means that only one host on a LAN can send a frame at any given time. The classic example of this is the original ethernet, but the modern ...
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9 votes

Can a single optical fiber support full-duplex communication?

Can a single optical fiber support full-duplex communication? Yes. There are "BX" standards, e.g. 100BASE-BX, which use different wavelengths for send and receive. The transmit wavelength on one end ...
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6 votes

The recommended settings for giga ethernet connected to Ethernet port

In reality, the legacy 10 Mbps ethernet interface probably can't negotiate, and it can probably only do half duplex (very few 10 Mbps interfaces can do full duplex). You should let the 1 Gbps ...
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6 votes
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Better throughput with 100 Mb NIC setting

This is a buffering issue. I had the same problem with a new Level 3 circuit. Their NID apparently has no measurable buffers, so feeding it at a rate 10x the circuit rate (1000 vs. 100) leads to all ...
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5 votes
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The recommended settings for giga ethernet connected to Ethernet port

The very short answer: don't configure anything. Auto negotiation (or the lack thereof as Ron's detailed) works only when it's left alone. Manual settings can very easily cause problems either right ...
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5 votes

Full Duplex and Collision Domain

You seem to be confused about logical topology (bus, ring, star). Ethernet has a couple of different topologies, but token ring has only the logical ring topology. Full-duplex ethernet doesn't use ...
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5 votes

How LAN works in video games if only one station is permitted to transmit?

The (naive) answer is, or rather used to be, simple: It tranlates to each sender having to wait a tiny fraction of a second. There is no way around this because that's how the network works at a ...
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5 votes
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Static speed and duplex/no-negotiate causing input error

If you disable Auto Negotiation (AN) you need to make sure that both sides are configured in exactly the same way. There's isn't any point in doing that manually, actually, so you should have AN ...
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4 votes

Can a single optical fiber support full-duplex communication?

A full duplex or Bidirection communication meaning that it can support both stations transmitting and receiving simultaneously. To accomplish this, a single optical fiber with WDM technology is ...
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4 votes
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Auto Sensing in Modern Switching Equipment

This (autonegotiation) is explained in various sections of the IEEE 802.3 specifications. Auto-MDIX is mostly a function of gigabit interfaces being able to TX and RX on all four pairs. I don't ...
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4 votes
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Full Duplex and Half Duplex Channel Capacity

Think of a half-duplex connection as a single channel that you can turn around between packets. Then think of a full-duplex connection as two unidirectional channels that can be used simultaneously. ...
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4 votes

Static speed and duplex/no-negotiate causing input error

By manually setting the speed and duplex on one side with automatic detection on the other side, the side with automatic speed will detect (not negotiate) the correct speed. For the duplex, ...
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3 votes
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Can we use two pairs of UTP with hubs?

Hubs do use two pairs for 10BASE-T or 100BASE-TX. One pair is for transmit, and one for receive; that is how the device interfaces are made, and the hub is really just a cable extension. What you need ...
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3 votes

Can we use two pairs of UTP with hubs?

No. There's a misunderstanding. A UTP cable consist of 8 wires, arranged in pair, so you have 4 pairs of wire in a single cable. Each pair is twisted, to reduce crosstalk and some kind of ...
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3 votes
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Can a half duplex communicate with a full duplex device

If you're asking about ethernet duplex, then the full- or half-duplex nature of a given link is negotiated when the link comes up, or alternatively set in configuration. (See autonegotiation at ...
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3 votes

How can 1000BaseT transmit on Rx & receive on Tx pins?

In 1000base-T there is circuitry called a hybrid which make the signal bidirectional. It's not really transmitting and receiving the wrong way round on the receive and transmit pairs, it's ...
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3 votes

How can 1000BaseT transmit on Rx & receive on Tx pins?

Why couldn't 10-BaseT (10Mb/s) or 100-BaseT (100Mb/s) do the same? What changed, specifically to allow this? The quality of the cabling improved drastically as well as the methods for transmitting ...
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3 votes

Does Time division duplexing work this way?

Time division duplex (TDD) concerns at least a 2 way communication. For example, a discussion is taking place between two people, say a and b, a talks whilst b listens, then b talks whilst a listens. ...
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3 votes
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Does duplex depend on the cable or the interface?

Cisco is being a bit literal. 10/100 "T" (twisted pair) does have independent TX and RX conductors. In a point-to-point situation, the link is fundamentally full-duplex. However, when a hub ...
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3 votes
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Why is a switch port a collision domain?

A collision domain is created by a port running in half-duplex mode (due to requiring media arbitration using CSMA/CD). The collison domain spans all ports within the same layer-1 segment - it crosses ...
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2 votes
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Negotiation speed/duplex between a Gigabit ethernet switch or hub and NIC

By manually setting the speed and duplex on one side with automatic detection on the other side, the side with automatic speed will detect (not negotiate) the correct speed. For the duplex, ...
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2 votes

How is TCP duplex if Ethernet is half-duplex?

To me the following analogy works: Think about you and your friend communicate each other by sending letters. You and your friend send/receive in full duplex manner but let's say the post office ...
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2 votes

How is TCP duplex if Ethernet is half-duplex?

Ethernet is a half duplex protocol, however, it was created in the 1980's about 30 years ago. At which time an Ethernet segment was shared between devices using a hub and all PC's shared the same ...
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  • 21
2 votes

Technical difference between a Collision and Broadcast Domain

(this post is in the context of Ethernet, other procols may vary) What criteria is used to know the boundaries of a collision domain? A collision domain is an area of a network where collisions ...
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2 votes

Multiple access and full/half duplex point-to-point links

Shared physical media: only one device on the shared media can access it at any given time, the rest has to wait. Halfduplex point to point links, uses the same physical media in both directions. It ...
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2 votes
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Difference between Half duplex and Full duplex

Half duplex can not send and receive at the same time. It also has algorithms to detect and handle collisions (CSMA-CD). Think of it like a walkie talkie or a CB radio, only on a network. Full duplex ...
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2 votes

Full duplex vs. half duplex

With a hub all ports are in a single collision domain meaning that all frames are visible on all ports and their connected devices. In a switch every port is its own collision domain so frames sent ...
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  • 21
2 votes

Full Duplex and Collision Domain

Whenever we read about Ethernet the first thing that we are taught is CSMA/CD. It says that in Ethernet two computers can not send data simultaneously. Unfortunately there is a lot of reference ...
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