Category Archives: Networking & Software

Category 6 Cable

Today’s bandwidth expectations mean that Category 5 is strategically dead. The Category 5 Enhanced (5e) standards, which should have been ratified in August and may be finalized at November’s committee meeting, specify new measurements that provide more margins for 100BaseTX and ATM-155 traffic. Critically, Category 5e standards make reliable Gigabit Ethernet connections possible. But many structured cabling suppliers argue that Category 5e is only an interim solution on the road to Category 6, which will support at least 200 MHz; in the interests of sufficient operating margin, the IEEE is requesting a 250-MHz Category 6 specification. Despite the fact that the Category 6 standards are only at draft stage, manufacturers are offering a host of products and claiming that these products comply with the draft proposals.

What is a category 6 cable? Out of the three cable categories (Cat-5, Cat-5e & Cat-6), Category 6 is the most advanced and provides the best performance. Just like Cat 5 and Cat 5e, Category 6 cable is typically made up of four twisted pairs of copper wire, but its capabilities far exceed those of other cable types because of one particular structural difference: a longitudinal separator. This separator isolates each of the four pairs of twisted wire from the others, which reduces crosstalk, allows for faster data transfer, and gives Category 6 cable twice the bandwidth of Cat 5! Cat 6 cable is ideal for supporting 10 Gigabit Ethernet, and is able to operate at up to 250 MHz. Since technology and standards are constantly evolving, Cat 6 is the wisest choice of cable when taking any possible future updates to your network into consideration. Not only is Category 6 cable future-safe, it is also backward-compatible with any previously-existing Cat 5 and Cat 5e cabling found in older installations.

Category 6, (ANSI/TIA/EIA-568-B.2-1) is a cable standard for Gigabit Ethernet and other network protocols that is backward compatible with the Category 5, category 5e and Category 3 cable standards. Cat-6 features more stringent specifications for crosstalk and system noise. The cable standard is suitable for 10BASE-T / 100BASE-TX and 1000BASE-T (Gigabit Ethernet) and is expected to suit the 10000BASE-T (10Gigabit Ethernet) standards. It provides performance of up to 250 MHz.

The cable contains four twisted copper wire pairs, just like earlier copper cable standards. Although Cat-6 is sometimes made with 23 gauge wire, this is not a requirement; the ANSI/TIA-568-B.2-1 specification states the cable may be made with 22 to 24 AWG gauge wire, so long as the cable meets the specified testing standards. When used as a patch cable, Cat-6 is normally terminated in 8P8C often incorrectly referred to as “RJ-45″ electrical connectors. Some Cat-6 cables are too large and may be difficult to attach to 8P8C connectors without a special modular piece and are technically not standard compliant. If components of the various cable standards are intermixed, the performance of the signal path will be limited to that of the lowest category. As with all cables defined by TIA/EIA-568-B, the maximum allowed length of a Cat-6 horizontal cable is 90 meters (295 feet). A complete channel (horizontal cable plus cords on either end) is allowed to be up to 100 meters in length, depending upon the ratio of cord length: horizontal cable length.

The cable is terminated in either the T568A scheme or the T568B scheme. It doesn’t make any difference which is used, as they are both straight through (pin 1 to 1, pin 2 to 2, etc). Mixed cable types should not be connected in serial, as the impedance per pair differs and would cause signal degradation. To connect two Ethernet units of the same type (PC to PC, or hub to hub, for example) a cross over cable should be used, though some modern hardware can use either type of cable automatically.

Return loss measures the ratio of reflected-to-transmitted signal strength and is the single most difficult test to repeat with consistent results; at Category 6 levels, the difference between a pass and a fail can be the amount of bend in a test cord. Return loss is also causing headaches for connector manufacturers, because the RJ-45 system isn’t up to the job. The final stumbling block with Category 5e ratification concerns the RJ-45 hardware; Category 6 is committed to RJ-45 for backward compatibility, but the ISO’s proposed Category 7 system will have a new and as-yet-unspecified connector to accompany its revised cabling. Today, the return loss problem explains why manufacturers of Category 6 hardware, which is supposed to be interoperable, claim Category 6 performance only if you use the manufacturers’ matched parts throughout a channel link.

The Telecommunications Industry Association (TIA) is working to complete a new specification that will define enhanced performance standards for unshielded twisted pair cable systems. Draft specification ANSI/TIA/EIA-568-B.2-10 specifies cable systems, called “Augmented Category 6” or more frequently as “Category 6a”, that operates at frequencies up to 500 MHz and will provide up to 10 Gbit/s bandwidth. The new specification has limits on alien crosstalk in cabling systems.

Augmented Category 6 specifies cable operating at minimum frequency of 500 MHz, for both shielded and unshielded. It can support future 10 Gb/s applications up to the maximum distance of 100 meters on a 4-connector channel.

Cabling your home for computer network

Cabling your home for computer network – still a requirement?

With proliferation of wireless networking and communication equipment it is oh-so-tempting to cut the cord and save a significant sum of money in the process. But is everything that a regular computer networking user needs can be done using just wireless network? Let’s take a look at some pros and contras:

1.    One important advantage of having a cabled network is the available bandwidth or simply speed. At the present point in time the speed of connection via a simple and inexpensive CAT5E cable can be 1000Mbit/sec, whereas the best that IEEE802.11g (one of the many flavors of Wi-Fi) can offer is only 54Mbit/sec. It may not seem so significant if you think you are only browsing Internet, and the DSL speed available to you is 1.5Mbit/sec. However, if you need to print via your network connection on a remote printer, you should realize that the print jobs, depending on the amount of graphic data in them, can easily reach dozens and even hundreds megabytes. Since 1Byte=8bit one 100MByte print job will take 15 seconds (and in reality this time can be much longer) to transmit via a Wi-Fi wireless connection, and this time shrinks to mere 1 sec or less on wired 1000MBit/s Ethernet connection. Same principal applies to transferring files, backing up files on other computers in the network etc.
2.    It is not possible today and with all probability will not be possible in the future to transmit power needed for your networking device via the wireless link. Unless, of course, you would be willing to be subjected to very high levels of microwave radiation. Thus a device that was marketed to you as “un-tethered” will in fact be very much tethered via the power cord or will have to be re-charged every so often. The power requirements are increasingly important for devices that are expected to be always online, such as phone sets. Therefore it is best to have it connected via a cable that can deliver both power and the communication signal at the same time.
3.    Wireless communications are very much proprietary and require whole gamut of conversion equipment to transmit multi-media signals. The same CAT5E cable can without any modification support phone, computer network, balanced line level audio signal, baseband video signal as well as host of other, more specialized, control applications’ signals. With inexpensive adapters called “baluns” the same cable can carry significant number of channels of broadband television or carry a baseband video, such as security camera output, through great distances. All of those applications, except the computer network of course, will require specialized expensive conversion equipment if they needed to be transmitted via a Wi-Fi link.
4.    The cost benefit of not running wires around the house is not as simple as issue as it seems. Having installed a wireless network at home you have only eliminated the need to wire for a single application – computer network. A modern home, however, requires all kinds of wiring to run even without regard to computers. The power and phones are obvious examples, as well as thermostats and security systems. Pre-wired speakers are common and most homes today have intercom systems as a desirable option, and those also require extensive wiring. It is very likely that the same contractor running the intercom or security cables is qualified to run computer cables – CAT5E or better. If you are building a home, you should definitely check if computer cabling option is available in your new home, and our advice is to go ahead and purchase it before the walls close. It is going to be a pretty involved and expensive procedure to install the cables later. As an added cost benefit of a wired computer network you will find that all modern computers ship with wired Ethernet network interface card included, and the latest models ship with 1000MBit/sec cards that are essentially free for the computer’s owner.

There are multiple sources of information available on proper planning and design of a residential cabling for voice, data, audio, video and other applications. One of the best sources is the TIA/EIA-570B standard, most resent release of which has been published in 2004. The standard outlines recommended types of the cables, principals of cable distribution in a single- and multi-dwelling units as well as recommended amount of cables to be installed based on the size of the house.

In conclusion, cutting the wire seems like a step forward, some sort  of liberation of computer from the bonds of the infrastructure. I would caution the reader, however, to take a more balanced and informed approach before joining the wireless revolution. There are still (and will remain in foreseen future) sound reasons to include properly designed cabling system into the list of your dream home options.

An Overview of Mobile Wireless Computing

Being able to work while traveling is essential for every professional these days. That’s why laptops have become an essential item. Using the internet on a laptop is also important if one needs to keep in touch with work. Getting wireless internet for your laptop is therefore essential if you are a traveling professional. It is important that if you do so, get a wireless internet capability for your laptop, to get the best possible deal out there and maximize the potential of your computer. Due to the mobility of the laptop, computer users need not to be limited by wires when travelling so wireless internet is very handy. Wireless internet these days is becoming better and faster and almost a necessity for every laptop.

Having wireless internet on your laptop allows the user to conduct their business in a timely and easy manner. Having a wifi internet connection on the laptop for example, makes conducting business much easier. It is becoming increasingly popular as well. Being able to connect to the internet while traveling allows the user to check emails constantly and therefore keep contacts, to have access to information like checking figures, and enhance their productivity. To be able to connect to the internet using a laptop, the computer must have the wireless capability to connect to a router. It is imperative that the laptop must have the right network card with a WiFi connector. There are many public spaces that allow for WiFi connections in every western city. The quality of the connection differs from place to place since it depends on a variety of factors. In general, the quality of the connection depends on the quality of the wireless signal that your laptop receives. Being closer or further from the source of the signal in the end will determine the strength and therefore the quality and possibly the speed of your connection. A WiFi network allows for constant connectivity in all hours of the day and every day of the week.

Currently, computer and consequently laptop manufactures are investing time and money in enhancing their products networking capabilities and speeds. In the past few years, wireless connectivity has come a long way in terms of quality and strength. When the portable computers were introduced a few years back the notion of the mobile network already existed. Nevertheless, it was not perfected and had many flaws. Over the years however, wireless capabilities have expanded, they have been bettered allowing for greater connectivity, stronger networks, and higher productivity. As a result, and due to the constant technological advancements, laptop users these days can buy the computer and never have to worry about finding a modem, or a router or those inconvenient cables. Just turn on the computer and start surfing the web. Due to the increasing popularity o wireless internet public spaces have been accommodating for this new trend. Public libraries, airports, or even specific businesses provide wireless internet for their customers. In many city centres in North America, there are so many wireless networks functioning at the same place that it is virtually impossible not to find an internet connection to log on to. The only down side to wireless computing is that it might be associated with health risks that we are not yet aware of. Overall, however wireless computing is the way to go for the business professional, the student or every other avid computer user.