Netwire - Network Administrators Coding of Ethernet cables

The information listed here is to assist Network Administrators in the color coding of Ethernet cables. Please be aware that modifying Ethernet cables improperly may cause loss of network connectivity. Use this information at your own risk, and insure all connectors and cables are modified in accordance with standards. Terminal Madness cannot be held liable for the use of this information in whole or in part.

T-568A Straight-Through Ethernet Cable


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The TIA/EIA 568-A standard which was ratified in 1995, was replaced by the TIA/EIA 568-B standard in 2002 and has been updated since. Both standards define the T-568A and T-568B pin-outs for using Unshielded Twisted Pair cable and RJ-45 connectors for Ethernet connectivity. The standards and pin-out specification appear to be related and interchangeable, but are not the same and should not be used interchangeably.

T-568B Straight-Through Ethernet Cable

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Both the T-568A and the T-568B standard Straight-Through cables are used most often as patch cords for your Ethernet connections. If you require a cable to connect two Ethernet devices directly together without a hub or when you connect two hubs together, you will need to use a Crossover cable instead.

RJ-45 Crossover Ethernet Cable

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A good way of remembering how to wire a Crossover Ethernet cable is to wire one end using the T-568A standard and the other end using the T-568B standard. Another way of remembering the color coding is to simply switch the Green set of wires in place with the Orange set of wires. Specifically, switch the solid Green (G) with the solid Orange, and switch the green/white with the orange/white.

Ethernet Cable Instructions:

  1. Pull the cable off the reel to the desired length and cut. If you are pulling cables through holes, its easier to attach the RJ-45 plugs after the cable is pulled. The total length of wire segments between a PC and a hub or between two PC's cannot exceed 100 Meters (328 feet) for 100BASE-TX and 300 Meters for 10BASE-T.
  2. Start on one end and strip the cable jacket off (about 1") using a stripper or a knife. Be extra careful not to nick the wires, otherwise you will need to start over.
  3. Spread, untwist the pairs, and arrange the wires in the order of the desired cable end. Flatten the end between your thumb and forefinger. Trim the ends of the wires so they are even with one another, leaving only 1/2" in wire length. If it is longer than 1/2" it will be out-of-spec and susceptible to crosstalk. Flatten and insure there are no spaces between wires.
  4. Hold the RJ-45 plug with the clip facing down or away from you. Push the wires firmly into the plug. Inspect each wire is flat even at the front of the plug. Check the order of the wires. Double check again. Check that the jacket is fitted right against the stop of the plug. Carefully hold the wire and firmly crimp the RJ-45 with the crimper.
  5. Check the color orientation, check that the crimped connection is not about to come apart, and check to see if the wires are flat against the front of the plug. If even one of these are incorrect, you will have to start over. Test the Ethernet cable.


Ethernet Cable Tips

A straight-thru cable has identical ends.
A crossover cable has different ends.
A straight-thru is used as a patch cord in Ethernet connections.
A crossover is used to connect two Ethernet devices without a hub or for connecting two hubs.
A crossover has one end with the Orange set of wires switched with the Green set.
Odd numbered pins are always striped, even numbered pins are always solid colored.
Looking at the RJ-45 with the clip facing away from you, Brown is always on the right, and pin 1 is on the left.
No more than 1/2" of the Ethernet cable should be untwisted otherwise it will be susceptible to crosstalk.
Do not deform, do not bend, do not stretch, do not staple, do not run parallel with power cables, and do not run Ethernet cables near noise inducing components.

Basic Theory

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By looking at a T-568A UTP Ethernet straight-thru cable and an Ethernet crossover cable with a T-568B end, we see that the TX (transmitter) pins are connected to the corresponding RX (receiver) pins, plus to plus and minus to minus. You can also see that both the blue and brown wire pairs on pins 4, 5, 7, and 8 are not used in either standard. What you may not realize is that, these same pins 4, 5, 7, and 8 are not used or required in 100BASE-TX as well. So why bother using these wires, well for one thing its simply easier to make a connection with all the wires grouped together. Otherwise you'll be spending time trying to fit those tiny little wires into each of the corresponding holes in the RJ-45 connector. 

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SURVEILLANCE SELF-DEFENSE

TIPS, TOOLS AND HOW-TOS FOR SAFER ONLINE COMMUNICATIONS A PROJECT OF THE ELECTRONIC FRONTIER FOUNDATION

https://ssd.eff.org/

The Electronic Frontier Foundation, an independent non-profit working to protect online privacy for nearly thirty years. This is Surveillance Self-Defense : The expert guide to protecting you and your friends from online spying.

Read the BASICS to find out how online surveillance works. Dive into our TOOL GUIDES for instructions to installing our pick of the best, most secure applications. We have more detailed information in our FURTHER LEARNING sections. If you’d like a guided tour, look for our list of common SECURITY SCENARIOS.

Check out the FULL article here:

https://ssd.eff.org/

 

 

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Victory! Supreme Court Says Fourth Amendment Applies to Cell Phone Tracking

 
https://www.eff.org/deeplinks/2018/06/victory-supreme-court-says-fourth-amendment-applies-cell-phone-tracking
 
 
The Supreme Court handed down a landmark opinion today in Carpenter v. United States, ruling 5-4 that the Fourth Amendment protects cell phone location information. In an opinion by Chief Justice Roberts, the Court recognized that location information, collected by cell providers like Sprint, AT&T, and Verizon, creates a “detailed chronicle of a person’s physical presence compiled every day, every moment over years.” As a result, police must now get a warrant before obtaining this data.
This is a major victory. Cell phones are essential to modern life, but the way that cell phones operate—by constantly connecting to cell towers to exchange data—makes it possible for cell providers to collect information on everywhere that each phone—and by extension, each phone’s owner—has been for years in the past. As the Court noted, not only does access to this kind of information allow the government to achieve “near perfect surveillance, as if it had attached an ankle monitor to the phone’s user,” but, because phone companies collect it for every device, the “police need not even know in advance whether they want to follow a particular individual, or when.”
For years, the government has argued that the sensitive nature of this data doesn’t matter; the mere fact that it’s collected by phone companies makes it automatically devoid of constitutional protection.
This argument is based on an outdated legal principle called the “Third Party Doctrine,” which was developed by the Supreme Court in two main cases from the 1970s involving records of phone calls and bank transactions. Courts around the country had long been deeply divided on whether the Third Party Doctrine should apply to cell phone location information or whether the invasiveness of the tracking it enables should require a more privacy-protective rule.
...there is a “world of difference between the limited types of personal information addressed in” prior Supreme Court cases and “the exhaustive chronicle of location information casually collected by wireless carriers today.”
EFF has been involved in almost all of the significant past cases, and in Carpenter, EFF filed briefs both encouraging the court to take the case and urging it to reject the Third Party Doctrine. We noted that cell phone usage has exploded in the last 30 years, and with it, the technologies to locate users have gotten and continue to get ever more precise.
Thankfully, in Carpenter, Justice Roberts rejected the government’s reliance on the Third Party Doctrine, writing that there is a “world of difference between the limited types of personal information addressed in” prior Supreme Court cases and “the exhaustive chronicle of location information casually collected by wireless carriers today.” The Court also explained that cell phone location information “is not truly ‘shared’ as one normally understands the term,” particularly because a phone “logs a cell-site record by dint of its operation, without any affirmative act on the part of the user beyond powering up.”
We were pleased that the Court cited our amicus brief in its opinion and agreed with many of the points we raised. In particular, Justice Roberts noted that because cell phones generate a record of location information all the time and “because location information is continually logged for all of the 400 million devices in the United States—not just those belonging to persons who might happen to come under investigation—this newfound tracking capacity runs against everyone.” What’s more, cell phone tracking enables the government to compile an “exhaustive chronicle of location information” so that “unlike the nosy neighbor who keeps an eye on comings and goings, [phone carriers] are ever alert, and their memory is nearly infallible.”
As we pointed out, this means that the government can engage in long-term monitoring. In Carpenter, for example, the government obtained 127 days of the defendant’s cell phone records from MetroPCS—without a warrant—to try to place him at the locations of several armed robberies around Detroit. Other cases have involved even longer periods of time. In a footnote, the Supreme Court declined to reach the question of whether very short periods of tracking, less than the 7 days used at trial in Carpenter, might not be covered by the Fourth Amendment. We think the right rule is to require a warrant for any cell phone tracking, but that will have to wait for another day.
Perhaps the most significant part of today’s ruling for the future is its explicit recognition that individuals can maintain an expectation of privacy in information that they provide to third parties. The Court termed that a “rare” case, but it’s clear that other invasive surveillance technologies, particularly those than can track individuals through physical space, are now ripe for challenge in light of Carpenter. Expect to see much more litigation on this subject from EFF and our friends.
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