Structured-Cabling,Data Cabling

Network Design Principles – Part 2

30 Sep 2018

Reliable & Manageable Scaling

Structured-Cabling,Data CablingScalability is a crucial characteristic that must be considered by network designers.

In addition, a network should also be reliable and manageable, which promote stability.  A network may be capable of expanding to several thousand routers. However, if there is a failure of some sort that causes instability due to greater processing and CPU usage required to compensate, the design won’t be successful.

A scalable network that is a challenge to manage or troubleshoot is also unacceptable.

Network problems that arise would take an excessive amount of time to address and repair, negatively impacting an organization’s business goals of the organization.

Thus, a scalable design must provide a manageable and reliable network.

Combining scalability, reliability, and manageability as the qualities of a network is a challenge. As a network expands, it becomes more complex, making management, maintenance, and repair more difficult.

Fault Isolation & Simplicity

Providing fault isolation boundaries creates fail-stop behavior for the wanted fault model. Fail-stop prevents faulty behavior from propagating past a fault isolation boundary. Effective network design must prevent a failure in one domain from spreading to other domains within a network. This is essential for the avoidance of unneeded processing and delays throughout the whole network because of a device or link failure. In addition, this will result in a converging network that has more stability, reliability, and speed.

The above concept also promotes simplicity as a network architecture characteristic, which decreases complexity in operations. Typically, fault isolation stops the propagation of network fault information across several domains or network areas. This will lead to greater network stability and the minimization of recovery time after failures.

The negative consequences due to a failure of a link or network node may spread to all devices across a network, resulting in a large volume of unneeded processing. A properly designed network using the Fault Domains Principle with its logical separation will limit the negative impact to within one fault domain.

Progressive Office Cabling

Founded in 1986, Progressive Office’s success has been a direct result of years of commitment to seeking solutions on behalf of our clients in the Washington, D.C. and New York City areas. Efficiently working together, Progressive teams get cabling installed and operating as fast as possible while minimizing disruption and downtime. Call our toll free number (800) 614-4560 today.

Network Cabling, Data Cabling

Windows 7 Was Not My Idea

23 Aug 2010

Network Cabling,Data cablingSo, I bought a new Acer Aspire One Netbook for my wife and for home use. It is a terrific little machine. It comes with Windows 7, 1gb RAM, a 160gb hard drive, 3 USB ports, external video jack, 10" LCD screen, 100mb ethernet, WiFi, cam and a microphone for only $325. And it weighs just over 2 pounds.

But when I went to install my printer to the machine I ran into a problem. I have a HP LaserJet 1320TN at home. It has been a terrific printer. It has 2 trays and it prints on both sides of a page. It has never had a single problem. I think the printer is about 7 or 8 years old. So, I get out the CD that came with the printer and I copy it onto a thumb drive because the netbook does not have a CD drive. Then I try to install it but it just doesn't work. The printer software is too old.

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Office Cabling, Network Cabling

Laser Printer Technology and Advantages

24 Dec 2009

                                                                 Office Cabling, Network CablingLaser printers are the most expensive type of printer in terms of running costs, due to the cost of the toner cartridges. But the cost per page for black and white printing is usually less than for inkjet printers.

The toner is the same type of toner used in photocopiers. And laser printers emulate the final stage of what a photocopier does by using a statically charged drum to attach toner to the paper. No liquid ink is used. The powdered toner is statically stuck to the paper when it passes over the rollers, and is then very quickly heated to fuse it to the page. The laser market is predominantly black and white, as nearly all businesses use the technology to produce cost-effective printouts. Laser printers ability to produce crisp, exact quality for text makes it the best choice for printing most corporate documents.

Laser printers are now quite capable in printing graphics as well. But for clear, color printing, color laser printers are ideal. And as their prices continue to decline, they are becoming more popular. But, again as with color inkjet printing, the cost per page goesup dramatically with color laser printers because they use 3 or 4 toner cartridges.

The primary market for color laser remains companies who are looking toLaser printers ability to produce crisp, exact quality for text makes it the best choice for printing most corporate documents. (the quality of a well-done color laser printout is really something to behold), and professional reprographics companies. But further price competition is making color laser a viable option for home users.

Technicians,repair services

Our Disposable Society

19 Oct 2009
Technicians,repair servicesToday I was contacted by a potential customer that has an HP OfficeJet Pro 8500. He wrote that the printer is displaying a paper jam error message and that it seems to have a broken gear inside but that there is no evidence of paper actually jammed in the printer. The printer costs $300 to replace and he is concerned about  the costs of repair.

In my email response to him I wrote...

We charge $125 for on-site repair plus $3 for cleaning materials plus parts. The parts could be anywhere from a few dollars to over $100. The problem is that getting parts puts us at the mercy of the manufacturer because these machines are all proprietary. So, even if it just needs a gear, it might mean that we have to buy an entire internal printer assembly to get the gear. So, I can't tell you exactly
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Adding RAM to Your PC is Best Upgrade

7 Oct 2009
ram upgrade moduleScenario: PC is 3 or more years old and still running well. You demand a lot from it. Sometimes you have 4 or more Windows applications open at a time. It feels a bit sluggish and takes too long to open a program.RAM upgrade quote

Solution: Add RAM. If you have less than 4gb of RAM, you might get a performance boost by adding more RAM to your PC. I usually suggest putting the max RAM into a system as an upgrade. But, be careful. If you leave the old RAM inside, your computer might become unstable. It is best to test your computer after adding the RAM. And if your system crashes or doesn't reboot, remove the old RAM and use just all new RAM.

Most importantly, you need to make sure you are getting 100% compatible RAM. There are dozens of combinations of RAM specifications. So, check with us if you need any help. We can order and install exactly the right RAM for your computer(s) and install it for you too.

IT support, computer repair

Bad Power Supply

4 Oct 2008

bad power supplyHow do you know when you have a bad power supply? Well, the symptoms are fairly basic. I had a client call me last week. He said his computer would not turn on. So, I asked him to tell me if anything came up on the monitor. He said, "No, the monitor is blank". So, I asked if he could see any lights come on the CPU and he told me that the CPU's LEDs were also dark. So, I asked him to put his ear to the power supply and tell me if he could hear the fan turning. He said it seemed quiet.

So, as a final test, I asked him to carefully look at the power supply and to tell me if the fan is spinning. He said it was not. Therefore, the power supply was bad. The next trick was in looking up the exact make and model and finding a generic replacement that would fit into the system. We did and we were able to get his computer back up and working the same day.

Call Progressive Office if you need IT Support at 202-462-4290.

Data Cabling,cables

Dell GX270 Motherboards have Leaky and Broken Capacitors

8 Feb 2008

"There is a known problem with capacitors on the GX270 motherboard bulging and corroding... (Actually, this is a problem on a lot of systems... the GX270 and a few others have a more specific problem where the capacitors were overfilled)."

This came to my attention a couple of weeks ago when a client called with a PC that wouldn't boot. "It won't power on at all" she said.

The technician I sent quickly determined that the problem was the Motherboard, but why did it fail?

However we have discovered that the Nichon capacitors were not all produced outside control specifications. Rather the affected capacitors were limited to certain batches made during specific shifts during the manufacturing process. This means that not all GX270 motherboards are affected. Unfortunately, there is not specific way to determine which motherboards are affected and which are not.

Specifically the capacitors were filled with more liquid than required. After an approximate service life of 300 days and when the CPU reaches a core temperature of 64 degrees C they will begin to bulge and eventually overflow onto the motherboard causing a system crash and a "No Post" failure on boot. There is usually no data loss associated with this issue."

A quick call to Dell resolved the issue in no time at all. After I gave the person on the phone the service tag number and a description of the problem, he informed me that the Motherboard was still under an extended warranty (that ended Jan.31 2008) and they would send a replacement.

23hrs later, the board is at our office door! WOW! That was quick! Thanks Dell! I can't say that we've needed much from their tech support, but they certainly impressed us this time around.

This post was written on February 8, 2008 but more recently Dell has admitted to shipping out millions of computers with faulty capacitors on them. Even worse, they replaced many motherboards with more defective motherboards.  If you have an Optiplex GX270, I would call Dell immediately to see if it is an affected unit.