Build a Skype Server for Your Home Phone System
Safely Cutting Your Phone Line
To cut your incoming phone wires safely, you need a pair of wire cutters (or sharp scissors) with insulated handles, a roll of electrical insulation tape, and you need to follow a simple procedure to do the cutting (Figure 6).
Your phone wires are powered by the telephone company; that's why your regular telephone works during a power cut. Now, even if you've had the phone company disconnect you, your phone wires may or may not still have electrical power. Consequently, you must be careful not to short the wires when cutting them. Even a momentary short can be bad news. This can happen if you cut two or more wires at the same time (step 1). The solution is simple, cut only one wire at a time (step 2). As you cut wires, you should insulate their exposed ends with electrical tape (step 3).
Now, if this activity looks to be beyond your comfort zone, you always have the option of calling the phone company and having them send a technician to do the job for you. Even after paying for this to be done, your Skype savings will most likely recoup the cost in very little time.
For those readers who are security-conscious, and don't trust Skype as an application, building a Skype server has an added advantage. By placing the Skype server on your Internet connection outside your firewall, you gain the peace of mind that should a hacker break in to your server, or compromise Skype somehow, then as the server interfaces with nothing more than a copper phone line into your home beyond the firewall, any damage will necessarily be contained and limited to the Skype server outside the firewall. Worst case is that you'll need to do a reinstall on your Skype server, and perhaps, a better job of locking it down from a security point of view so that it can protect itself. Indeed, if your firewall is sufficiently restrictive that Skype won't work on the inside, then placing your Skype server outside your firewall is the only way in which you can take advantage of Skype's phone services.
Phone bills have a lot in common with taxes. Both are mind numbingly complex, and both take a lot and give little in return! To help work out your potential savings from switching to Skype for your phone services, in whole or in part, I've written a spreadsheet that simplifies the process and can be downloaded from the Elpis Web site (see the on-line Resources).
You should factor in the cost of building and running a Skype server into your savings analysis. Running costs will depend on the machine that you choose to use in order to run Skype 24/7. An old clunker of a machine may consume so much power that it would be worthwhile to build a new machine in the long run. As always, run the numbers and make some decisions.
Let's look at the cost of running a small Skype server 24 hours a day, 365 days a year. Without a monitor and other peripherals to guzzle power, a small modern computer typically consumes between 50W and 100W. If your cost of electricity is $0.10 per kWh, then the annual cost of running your Skype server is between $44 and $88. These are just ballpark numbers and you'll no doubt do your own, but it does show that the cost of running a Skype server 24/7 is not insignificant. (Cost = power consumed in kW x 365 days x 24 hours x cost per kWh, where a power consumption of 50W is 0.05kW and 100W is 0.1kW.)
Resources for this article: /article/8644.
Practical Task Scheduling Deployment
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
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|The Firebird Project's Firebird Relational Database||Jul 29, 2016|
|Stunnel Security for Oracle||Jul 28, 2016|
|SUSE LLC's SUSE Manager||Jul 21, 2016|
|My +1 Sword of Productivity||Jul 20, 2016|
|Non-Linux FOSS: Caffeine!||Jul 19, 2016|
|Murat Yener and Onur Dundar's Expert Android Studio (Wrox)||Jul 18, 2016|
- Stunnel Security for Oracle
- The Firebird Project's Firebird Relational Database
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- SUSE LLC's SUSE Manager
- Managing Linux Using Puppet
- My +1 Sword of Productivity
- Non-Linux FOSS: Caffeine!
- Doing for User Space What We Did for Kernel Space
- Google's SwiftShader Released
- SuperTuxKart 0.9.2 Released
With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide