|  | Technical Information About Category 6
What is Category 6?
Category 6 is the specification for data cabling systems to support data transmissions at very high speeds, offering a bandwidth of 250MHz. It provides an excellent platform for gigabit Ethernet (which uses complex encoding techniques to limit the required bandwidth to 100MHz), but also caters for future high speed data transmission protocols offering even higher data rates or providing the same data rates using less expensive encoding schemes.
Why use category 6 instead of Enhanced Category 5 Products?
If you are currently running fast Ethernet then installing Category 6 cabling now will enable you to make two technology leaps: to Gigabit Ethernet, and beyond. This will prevent future disruption to your business, which will easily offset the additional cost of installing Category 6 now. Enhanced Category 5 on the other hand might not be capable of supporting technologies beyond Gigabit Ethernet.
How has the product actually improved?
Enhanced Category 5 offers a tightly controlled cabling infrastructure offering a bandwidth of 100MHz. This is currently sufficient to support data rates up to 1000 Mbps. Category 6 expands on this by setting an upper frequency limit of 250Mhz. This allows existing protocols to operate with more headroom and provides the infrastructure to cope with future developments in data communication technology. This requires manufacturers to re-design their products completely, not just improve the performance of existing products.
When should I start using Category 6 Products?
If you are already running Fast Ethernet (or similar speed) now and you are currently thinking about re-cabling then you should think about installing Category 6 now. It will give you a network capable of supporting your data communication needs for years to come.
What are the advantages of using Category 6 Products?
1. Connectix Cabling System Category 6 products provide exceptional performance combined with full backward capability with our Enhanced Category 5 offering.
2. All our products are UK designed and tested.
3. Connectix offer a 15 year product warranty on all Category 6 products to ensure the performance and quality of our structured cabling products is guaranteed.
4. Connectix Cabling Systems Category 6 products incorporate the same installer friendly features as the Enhanced Category 5 range, including colour coding for quick and accurate terminations.
5. All Connectix Cabling Systems Category 6 Modular Outlets are fully interchangeable with standard faceplates and quarter blanks.
6. The Connectix Cabling Systems Category 6 system provides the extended performance characteristics required for future proofing your data network.
About Enhanced Category 5
What is Enhanced Category 5?
Enhanced Category 5 is a specification designed for data networks to support very high-speed transmission, like gigabit Ethernet, at a bandwidth of 100MHz. Enhanced Category provides Power Sum characteristics to support these data rates. Enhanced Category 5 replaced Standard Category 5 as our base line offering in 1999.
What is Power sum?
Traditionally crosstalk was only measured between any combination of two pairs within the cabling. Power Sum is a way of determining the crosstalk on an individual pair caused by the three other pairs in the cabling. This is of course crucial importance for Gigabit Ethernet, where all four pairs are used simultaneously.
How has the product actually improved from Category 5?
Standard Category 5 supported data rates up to 100Mbps across cabling infrastructures at a bandwidth of up to 100Mhz. Only a limited number of characteristics were specified. Enhanced Category 5 supports increased data rates (presently up to 1000 Mbps) across a cabling infrastructure offering the same 100MHz bandwidth. To achieve this, additional characteristics have been specified to provide a more tightly controlled cabling infrastructure. The circuitry of the Connectix Cabling Systems Enhanced Category 5 products has been improved using innovative on-board compensation techniques to provide performance in excess of the Enhanced Category 5 Specification.
When should I use Enhanced Category 5 products?
Installing Enhanced Category 5 will ensure that your network can support high speed applications like Gigabit Ethernet. If a data rate of 1 Gigabit per second to the desktop covers your data needs for the coming years then the Enhanced Category 5 is for you. If you anticipate a demand for higher data rates then read on about Category 6, or you might want to consider fibre to the desk.
What are the advantages of using Connectix Cabling System Enhanced Category 5 Products?
1. Connectix Cabling Systems Enhanced Category 5 products provide exceptional performance - well excess of the proposed specification.
2. All our products are UK designed and tested.
3. Connectix Cabling Systems offer a 15 year product warranty on all enhanced Category 5 products, to ensure the performance and quality of our structured cabling products is guaranteed
4. Connectix Cabling Systems Enhanced Category 5 products incorporate various features to make the job of installing them easy, including colour coding for quick and accurate terminations.
5. Our range of Enhanced Category 5 modular outlets are fully interchangeable with standard faceplates and quarter blanks.
What is the difference between Enhanced Category 5 and Class E?
Enhanced Category 5 products are specified up to 100 MHz. They can support very high-speed protocols like Gigabit Ethernet using complex encoding and de-coding techniques. Class E is the proposed Category 6 standard for systems performing up to 250MHz
Connectix Copper Cabling Systems
Cable monkey offers both Enhanced Category 5 and Category 6 Structured Cabling systems.
The Connectix Design team is constantly anticipating market and technological trends to bring innovative products to the market in the shortest possible time.
The result - one of the most comprehensive ranges of networking systems available. And, to ensure long life performance and reliability, Connectix Cabling Systems are manufactured from top quality components to the highest specifications.
Connectix Cabling systems have been installed in over 50 000 sites, with many leading companies already benefiting from Connectix Cabling installations. Connectix Commit to innovative design and development ensures all customers receive the very best integrated Cabling Systems for their specific needs.
UTP/FTP Solid Cable
Cable Monkey offers Enhanced Category 5 and Category 6 Solid Cable both exceed their performance specification.
Enhanced Category 5 cable is designed for high speed LANs including Gigabit Ethernet Applications.
Category 6 Cable is designed for use with next generation data generation data communications networks and will comfortably support all present applications including Gigabit Ethernet every box of Category 6 cable is individually tested in the UK
Both types of cable are despatched in 305m reelex boxes and are supplied metre marked for easy installation.
The cables are available in UTP (unfoiled twisted pair) and FTP (foiled twisted pair) types.
Cable Management
We offer a range of Cable management solutions that improves installation time and reduces congestion within the cabinet.
Our patented cable tidy rings have been designed specifically for Connectix Cabling System patch panels. Available in two sizes, the rings slot into a groove at the front of the panel, using these save you time, space and money. They eliminate the need for a separate cable tidy panel, thus saving you precious cabinet space plus they are quick to install as you only have to slide them into the panel. Blank panels are available if you require extra cable ring space.
Cable management trays fits securely onto the rear of any Connectix standard or high density patch panel, it provides additional cable tie positions to allow neat routing of cables from the back of the panel.
Our jumper ring panels allow patch leads to be supported and prevented from obscuring other equipment, they are available in two configurations either four rings for horizontal support or three for horizontal and two for vertical support.
Outlets
We offer outlets to cater for all your computer networking scenarios. Available as standard or compact sizes in both Enhanced Category 5 and category 6 our modular outlets offer exceptional performance exceeding their specifications. We also offer LJ6C modular outlets which are perfect for floor boxes or if you need a more corporate look, then our metal faceplates are ideal.
Connectix modules are available to buy singularly or as complete outlets. With such a wide choice we are sure that you will find the perfect solution for your networking needs.
Patch Panels
Connectix Cabling System Panels are available in Category 6 and Enhanced Category 5 variations. The panels are available as High density or standard (With the option of a second style of high density if ordering Enhanced Category 5 panels). Our panels are available as UTP or FTP depending on your requirements. All Connectix Cabling System panels are manufactured in the UK with top quality high performance sockets, each panel is QA tested.
Patch Leads
We have a range of booted and unbooted patch leads, available in nine different colours. Category 6 patch leads are booted as standard however our Enhanced Category 5 leads are available both with or without boots.
You can purchase leads from 0.5m up to 5m in length and all of our patch leads are individually QA tested prior to despatch.
Cable Management
We offer a range of Cable management solutions that improves installation time and reduces congestion within the cabinet.
Our patented cable tidy rings have been designed specifically for Connectix Cabling System patch panels. Available in two sizes, the rings slot into a groove at the front of the panel, using these save you time, space and money. They eliminate the need for a separate cable tidy panel, thus saving you precious cabinet space plus they are quick to install as you only have to slide them into the panel. Blank panels are available if you require extra cable ring space.
Cable management trays fits securely onto the rear of any Connectix standard or high density patch panel, it provides additional cable tie positions to allow neat routing of cables from the back of the panel.
Our jumper ring panels allow patch leads to be supported and prevented from obscuring other equipment, they are available in two configurations either four rings for horizontal support or three for horizontal and two for vertical support.
Outlets
We offer outlets to cater for all your computer networking scenarios. Available as standard or compact sizes in both Enhanced Category 5 and category 6 our modular outlets offer exceptional performance exceeding their specifications. We also offer LJ6C modular outlets which are perfect for floor boxes or if you need a more corporate look, then our metal faceplates are ideal.
Connectix modules are available to buy singularly or as complete outlets. With such a wide choice we are sure that you will find the perfect solution for your networking needs.
Patch Panels
Connectix Cabling System Panels are available in Category 6 and Enhanced Category 5 variations. The panels are available as High density or standard (With the option of a second style of high density if ordering Enhanced Category 5 panels). Our panels are available as UTP or FTP depending on your requirements. All Connectix Cabling System panels are manufactured in the UK with top quality high performance sockets, each panel is QA tested.
Patch Leads
We have a range of booted and unbooted patch leads, available in nine different colours. Category 6 patch leads are booted as standard however our Enhanced Category 5 leads are available both with or without boots.
You can purchase leads from 0.5m up to 5m in length and all of our patch leads are individually QA tested prior to despatch.
Fibre
Cable Monkey offers all the products needed to create the perfect Fibre Network. Multimode and Singlemode, connectors, leads and cables are available. We offer a full range of fibre accessories including Termination kits, Fyberscopes, patch panels, break out boxes and lightsource and power meter kits.
Terminated Assemblies
Patch leads and pigtails are available from 0.5metre up to 5metre in length, for all types of multimode and singlemode terminations and are available with a full range of connector types including ST, SC, LC and FC assemblies.
All of our terminated assemblies are 100% tested and certified, we use only top quality cable and connectors.
Connectors
Our range of fibre connectors include ST, SC, LC, FC and FDDI, with the option of both multimode and single mode variations on most types of connectors.
All of our connectors are manufactured to high quality standards and conform to the relevant specifications.
Patch Panels & Break out boxes
Our range of rack mount patch panels are available in 1u, 2u and 3u sizes with a wide range of adapter types and populations. The panels are manufactured from mild steel and are finished in a grey powder coating. The panels feature rear knock outs to suit three sizes of cable glands, the panels are numbered on the front face of the panel.
Our wall mount Break out Boxes are designed to provide a cost effective alternative to the patch panel. The break out boxes are Ideal for situations where equipment racks or cabinets are not available.
Another option to the patch panel or break out box is the Lockable wall mount box, These enclosures provide and ideal solution for secure patching in any location where a cabinet or other secure enclosure is not available. This wall box features two doors with different locks and an interchangeable internal panels which is available for a wide range of adapter types.
Uni-Loose Tube distribution Fibre Cable
Our multi-purpose uni-loose tube distribution cable provides highly cost effective solution to all internal or external datacomms cabling requirements particularly where on site fusion splicing of pigtails is the preferred termination technique. A choice of multimode and singlemode fibre types with fibre counts from four to twenty four available.
Their very small diameter, light weight and excellent environmental performance makes these cables ideal for installation in a broad range of networks and mixed indoor and outdoor cabling.
The cable consists of a single central uni-tube containing individually colour coded 250µm buffered fibres. This tube is embedded in an Aramid yarn strength member and oversheathed with a single Low Smoke Zero Halogen (LSZH) outer outer jacket. The outer jacket is flame retardant, UV stabilised and extremely resistant to the ingress of moisture.
Tight Buffered Distribution Cable
Our multi-purpose tight buffered distribution cable provides a highly effective solution to all internal/external cabling requirements, particularly when on site direct connectorisation is the preferred technique. A choice of multimode and singlemode types, with fibre counts from four up to twenty-four available. Their smaller diameter, light weight and excellent environmental performance make these cables ideal for installation in a broad range of network applications including LAN backbones, networks with mixed indoor and outdoor cabling, outdoor in flooded ducts and any premises distribution system.
The cable consists of individually colour coded 900µm secondary coated fibres, embedded in an aramid yarn strength member and oversheathed with a single Low Smoke Zero Halogen (LSZH) outer jacket in flame retardant, UV stabilised and extremely resistant to the ingress of moisture.
Uni Tube Corrugated Steel Armoured Cable
Uni Tube steel tape armoured cable is suitable for installation in the most demanding, harsh environments. The cable has excellent tensile strength and crush resistance characteristics and is also rodent proof.
The Tube consists of central jelly filled green polyester tube, with up to twenty four optical fibres inside. The tube is protected with Kevlar strength members and thick inner corrugated steel tape armour is then applied. A black LSZH outer sheath protects the cable construction and is extremely resistant to the ingress of moisture.
This tough rugged cable is ideal for all external environments including LAN direct burial, tunnels and heavy duty ducts.
SWA UNI TUBE Fibre Cable
SWA Uni-tube cable is suitable for direct burial installations making it the perfect solution for the most demanding and harsh environments.
The cable core consists of a central jelly filled green polyester tube, with up to 24 optical fibres contained within. The tubeis protected with aramid strength member and a 1.1mm thick FireBur® LSZH sheath plus a layer of 0.9mm galvanised wire armouring. All of which is surrounded by a 1.5mm thick black FirBur® LSZH sheath which protects the cable and construction and is extremely resistant to the ingress of moisture.
The tough rugged cable is ideal for all external environments including direct burial, tunnels and heavy duty ducts.
Wall Mounting Cabinets
The compact design of our wall mounting cabinets make them ideal fro smaller networks and workgroups. The wall units can be situated above work areas to allow more room for standing equipment.
The cabinets are available in various configurations and are supplied fully assembled.
Each cabinet has a lockable inset Perspex front door. The cabinet frameworks are finished goose grey.
The two part wall mounting cabinets incorporate many of the standard wall mounting cabinet features and when divided they allow maximum access to the internal equipment for convenient cable management.
The wall mounting frame is a cheap solution for smaller networks and workgroups where a cabinet is not required.
Active Networking Hardware
We offer a range of networking hardware that is suitable for the smaller workgroup. Our switches and converters all comply to the necessary IEEE standards and come with a 3 year warranty and advanced replacement.
Converters
The media converter was specifically designed to offer the network designer the tools for migration from copper to fibre.
The converters we offer suit the requirements of migration or expansion of existing networks with minimum cost and complexity.
Switches
5, 8 and 16 port switches are available from Cable Monkey. These switches are designed specifically for smaller workgroups. All ports are auto-negotiating, auto sensing, 10/100Mbps Ethernet. Presented on standards based RJ-45 connectors. When a connected device supports auto negotiation the switch and device will automatically switch to the best common mode of operation. If the attached device does not support the auto-negotiation then the switch will select the correct operating speed and default to half-duplex mode. Each of the ports will detect whether it needs to present itself as either an MDI or an MDI-X to connect to the link peer. This means that there is no need to worry about cross over cables or uplink ports on connected devices.
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| Information Continued Installation Practices
In order to meet the stringent requirements of the ISO/IEC 11801 and TIA/EIA-568-B specifications for Category 5 E and Category 6 wiring systems, it is essential that the following guidelines are adopted. This will ensure that the installation provides and efficient and reliable service throughout its lifetime.
- Cables should not be joined to increase length. If cables are found to be short they must not be re-routed by a less suitable path, but must be re-run.
- Cables must be secured so as to relieve any mechanical stress on the terminations.
- Cable ties must be finger tight only. Over tight ties deform the geometry of the cable and affect its link performance. They should not be so tight as to distort the outer sheath of the cable.
- Cable bundles should be limited to 50 cables to avoid crushing the lower cables in the bundle.
- Care must be taken to avoid kinks in the cable during cable pulling.
- Any cabling over suspended ceilings must be laid in standard cable trays and
supported every 1.2 to 1.5 metres to avoid any possible movement.
- The minimum bend radius during installation is 75mm and 25mm once installed.
- Do not use undue strain when cable pulling (Maximum 25lb).
- Avoid high temperature environments, power cable, lift shafts, switch gear and any other sources of interference.
- All cable runs should be concealed and cable routes e.g mini trunking, should run parallel or perpendicular to the walls.
- When cable routes pass through walls the holes must be sleeved and the cables exit and enter 90°to the wall.
- All cables must be free of tension along the entire route and cable supports should be used to distribute any strain.
- All metallic conduit and trunking must be earth bonded in accordance with IEE wiring regulations.
- All cable exits must be bushed or sleeved so as not to cause damage to the cable's outer sheath.
- Space should be left to allow for additional cables to be run in the existing cable routes. It is recommended that conduit and trays should not be filled to more than 80% fill capacity therefore leaving a minimum of 25% spare cable route capacity available for future system expansion.
Networking Basics
Network Topologies
There are fundamentally three different types of network topology. Topology refers to the "logical layout" of the network wiring.
Bus
A bus-based network uses a single piece of cable to connect all the devices together. Each end of the cable has a 50 W terminator which absorbs any signal that it receives. Without a terminator on either end, the network will fail. This is a Coax Cable network
Star
A star based network has a central hub that connects all the stations to one another. Twisted pair cable is used with this network
Ring
A token ring network is organised in the same way as a star network. Instead of a 'hub' a token ring network uses a device called a MultiStation Access Unit (MSAU).
A token ring network does not use CSMA/CD technology so it does not fall under the Ethernet umbrella of 802.3. A separate subcommittee with a firm lead from IBM developed IEEE 802.5 which describes the token-passing technique.
Ethernet and IEEE 802.3
The Ethernet cabling and signalling specifications were originally developed by Xerox in the 1970's. In 1980, Digital Equipment Corporation (DEC), Intel and Xerox began joint promotion of the Ethernet philosophy. This joint venture produced the successor to Ethernet, Ethernet version 1. This standard was later enhanced, in 1985, this enhancement was known as Ethernet version 2.
The IEEE (Institute of Electrical and Electronic Engineers) project 802 decided to use Ethernet version 2 as the basis for its new CSMA/CD network standard. By enhancing the DEC, Intel and Xerox Ethernet 2 design, they produced the IEEE 802.3 specification, which is now the standard format for Ethernet based systems.
The IEEE 802.3 specification describes Ethernet based networks. As we have already discussed, there are four types of cable that are traditionally used on Ethernet; 10base5, 10base2, 10baseF, 10baseT and 100BaseT cable.
The name 10Base indicates a signalling speed of 10 million bits per second (about a thousand times faster than a 9600-baud serial interface) with a baseband signalling scheme. The number, or letter, that follows usually indicates the maximum length of the cable in metres. Consequently 10base5 cabling can have a maximum length of 500 metres, whilst 10base2 cabling can have a maximum cable length of 200 metres. 10BaseF cabling signifies fibre optic cabling which can have a maximum length of 2,000 metres. 10baseT cabling stands 'twisted pair' which has a maximum cable length of 185 metres.
- 10Base2 10Mbs Ethernet running over thin, 50 Ohm coaxial cable.
- 10Base5 10Mbs Ethernet running over thick, 50 Ohm coaxial cable.
- 10BaseF 10Mbs Ethernet running over fibre optic cable.
- 10BaseT 10Mbs Ethernet running over twisted pair cable.
- 100BaseT 100Mbs Ethernet running over twisted pair cable.
Other 802.x standards
The IEEE committee are also responsible for other 802 networking specifications:
- 802.1, this group produced an overview of the work of the project and defined the LAN reference model.
- 802.2, this describes the logical link control services used in all IEEE specified LANs.
- 802.3, describes Ethernet based networks.
- 802.3z, describes the Gigabit Ethernet format.
- 802.4, describes networks using a token-passing bus.
- 802.5, describes networks using a token-passing ring.
- 802.6, specifications for a metropolitan area network.
- 802.7, this group advised other working groups on issues relating to broadband transmission.
- 802.8, this group are the technical advisory group for FDDI and fibre optic.
- 802.9, this group explores integrated data and voice networks.
- 802.10,
- 802.11b, Wireless Ethernet 11Mbps in the 2.4GHz Band
- 802.11a, Wireless Ethernet approx 50Mbps in the 5GHz Band
- 802.12, Group working on the implementation of 100VG-AnyLAN.
10Base5
A 10base5 cable segment may be up to 500 metres long and may carry up to 200 interface points (transceivers). If you are using 10base5 cabling there must be a distance of 2.5 metres between individual transceivers.
10Base2
Thin Ethernet (Cheapernet). 10base2 is thinner and more flexible than 10base5 which makes it easier to install than the thicker 10base5 cabling. Although the maximum cable length and number of interface points is less than half of 10base5, it usually isn't an issue as 10base2 networks are generally smaller than 10base5 networks.
10BaseF
Fibre optic cabling, 10BaseF, is generally used to connect one building to another. It is possible to connect your office based network via 10BaseF cabling, however, as the cost would be prohibitively high, it could only be recommend for the most specialised environments.
10BaseT
10baseT (also known as twisted pair). Distances of up to 30 metres between the connected stations and a junction box may be bridged using two-wire circuits. The stations are arranged in a star shape around each junction box or hub.
100BaseT
The 'next generation' of 10BaseT networking. This version runs at ten times the speed of 10Mbit Ethernet, therefore data transfer is theoretically ten times faster. Most manufacturers are now marketing 10/100Mbit Ethernet adapters. This means that the card can function on both a 10BaseT and 100BaseT network. Most manufacturers still market conventional 10Mbit technology as their 10Mbit technology usually has a 10BaseT and 10Base2 connector. The 100Mbit technology usually only has a single connection that can be used on both 10BaseT and 100BaseT networks.
Gigabit Ethernet
As more bandwidth hungry applications appear on the market, for example, video conferencing, large colour documents, then the industry has decided that there should be an even faster networking standard. One of the solutions is known as 1Gigabit Ethernet. Gigabit Ethernet employs the same CSMA/CD protocol as its predecessors. This means that for the majority of users, the investment required to upgrade to Gigabit Ethernet is minimal. Because of these attributes, Gigabit Ethernet will be an ideal backbone interconnecting 10/100Base-T switches or as a connection to high performance servers.
Ethernet and CSMA/CD
Ethernet uses the Carrier Sense Multiple Access with Collision Detect (CSMA/CD). In simple terms: before a station sends a packet, it checks to see if any other station is already active (carrier sense). If it is, it waits until the cable is free, otherwise it transmits immediately. When the inevitable happens, when two or more stations simultaneously start to transmit on an idle cable and the transmissions collide, the adapters are able to detect the collisions. The adapters can detect collisions because of the higher electrical signal level that simultaneous transmissions produce. When they detect a collision, the network adapter cards begin transmitting a jam signal to ensure that all the conflicting stations notice the collision. After this each adapter stops transmitting and goes into a "back-off" period. This back-off period ensures that the stations don't continue to send out colliding signals every time the cable grows quiet.
Imagine the scenario: Station A and Station B both want to send a message over the network cabling. When station A checks to see if the cable is busy, it finds that everything is OK and starts to send the data.
As station A is sending the data Station B listens to the network cable to see if it can send its data, as the data from Station A has not yet reached Station B, it decides that the network cable is quiet and therefore starts to send its information.
Two stations sending data to one another will ultimately cause a collision.
When the data collision occurs both stations stop sending data and start to send a jam signal through the cabling to inform another other network devices that there has been a data collision.
Once all stations have received the jam signals they all then go into a back-off period. Each network card must wait a random amount of time before it attempts to start sending data again. The length of time that cards sit in this back-off period must be different for each network device, if they were not different then the network cards would start to send data at the same time, which would cause another data collision.
Now when Station A starts to send data it manages to send all its information before Station B attempts to communicate.
Layout of an Ethernet frame
In the Ethernet protocol, messages are sent between workstations in the form of "packets", or frames. Each packet measures 72 to 1,526 bytes long and contains six fields, five of which are fixed length.
The 8-byte preamble is split into two sections. The first 62 bits are a series of binary 1's and 0's - the last 2 bits represent the frame delimiter. The preamble field allows the receiving station to synchronise with the transmitted message. The destination and source address fields contain the network ID of the nodes receiving and initiating the message; the type field indicates the type of data in the data field which contains the actual data; the CRC field helps the receiving node perform a cyclic redundancy check.
Preamble Destination Source
Address Address
(8 bytes) (6 bytes) (6 bytes)
Type Data CRC
Field Field
(2 bytes) (46-1,500 bytes) (4 bytes)
If the data to be sent over the network is less than 46 bytes it will be padded out to the minimum 46-byte length.
Network Operating Systems
As well as different cabling types and speeds, people also have to decide which network operating system they are going to use. There are several choices:
Novell Netware
Novell have been involved in networking for many years, like all software manufacturers their product has slowly evolved. Their current release is Intranet Ware version 4.11. This version allows the administrator to build a WWW and FTP server.
Novell file servers run on dedicated computers that can not be used for any other purpose, you can't run Windows on a Netware fileserver, you can't shell out to a DOS prompt, a Netware fileserver does only one thing.
Netware 3.x systems do not have something called NDS (Netware directory services), when Novell introduced Netware 4, NDS support was provided. When Novell introduced Netware 4.11 Intranetware they included software to create WWW and FTP servers.
A Netware network is known as a client server network as the Netware fileserver forms the heart of the network, without it the client computers would not be able to send mail, print or share data with their colleagues.
The disadvantage of Netware is that it is not the easiest piece of software in the world to use. However, Novell have produced graphical management systems that are easier to use that previous releases.
Microsoft Windows NT
NT is Microsoft's network operating system. Their current release is version 4 (NT 4). An NT 4 server is different to a Novell server in that, if you wanted to, you could install Word, Excel, etc… onto the server and run those applications at the same time as handling all network requests, however, this isn't really a sensible thing to do.
NT 4 is much easier to use as it has the familiar Windows 95 look and feel. NT 3.5 and NT 3.51 has the look and feel of Windows 3.1 and 3.11.
One of the problems of NT is its maturity, it does not have the pedigree of Netware file servers, consequently Microsoft are forever producing Service Packs for their software. These service packs fix bugs, and generally also add to the functionality of the product.
Just like a Netware fileserver, Windows NT is know as a client server network. Without the NT server, you will not be able to e-mail, print or share data with colleagues.
LanManager
Lan Manager was a joint collaboration between Microsoft and IBM. There was a lot of excitement about Lan Manager when it was released, however, Microsoft decided to abandon the project in favour of Windows NT.
As with Netware and Windows NT systems, Lan Manager is a client server based network.
Windows 3.11 and Windows 95
It is possible to build a small network with both Windows 3.11 and Windows 95. This type of network is know as a peer to peer network.
Unlike a client server network, data is stored on individuals PCs, printing is controlled by individual PCs. If a PC is switched off, then only the data stored on the PC will unavailable, any other 'shares' will still be accessible by other users.
Peer to peer networks have their place, in small office environments they offer simple file and printer sharing. However, they are not designed to compete with environments where there are many users.
Apple Macintosh Systems
The Macintosh is a nice piece of software and hardware, unlike the PC, it has been designed to be used straight away. PCs users have had to fight with DIP switches, interrupts, base addresses, ISA, PCI, for years. Macintosh users, on the other hand, haven't had to worry about this. They just got on with their jobs and used their machine.
The trouble with the Macintosh is that not enough people bought them. Whilst everyone was cloning PCs, no one, was able to clone the Mac. In the end, the PC became too popular and the PC with DOS and Windows won the battle.
Because there are relatively few Macintoshes in relation to PC servers running Netware or NT. The Mac environment is ignored by many organisations. Desktop publishing people now use Macintoshes, they are not used extensively as fileservers.
Unix Systems
Windows NT and Netware are fine for small to medium sized organisations and are becoming more powerful year by year, however, they are regarded by some as mid-range solutions that are prone to crashing and not fast enough for their daily activity.
Unix systems run on a variety of platforms, Sun Sparc stations, HP servers etc… These servers are generally equipped with massive amounts of memory and hard disc space. Databases are measured in terabytes and physical memory is measured in hundreds of megabytes. In short, they are seriously powerful.
Usually they're running the TCP/IP protocol and are ideally suited to be WWW and FTP servers. What Windows NT and Netware have now, Unix systems have had for years!
Useful Terms
UTP Cable:
Unshielded Twisted Pair cable is the standard cable used for typical installations that do not need any special requirements. Consists of 4 pairs (8 wires)
STP/FTP Cable:
Shielded or Screened/ Foiled Twisted Pair Cable is used mainly in industrial environments to reduce electrical interference. Consists of 4 pairs (8 wires), foil screen and drain wire.
RJ45 Plugs
These are 8 pin industry standard connectors. Originally derived from the RJ11 & RJ12 telecom connector.
Voice/PBX converters
Converter from RJ45 to BT style telephone plug complete with ringing circuit.
Patch Panel/Distribution Panel
Patch Panel/Distribution Panel. Usually a 19 inch rack/cabinet mounted, RJ45 outlet panel with IDC termination points at the back. Available at competitive prices from Cable Monkey as 16, 24HD, 32, or 48 ports
Testing Optical fibre
Testing Optical Fibres requires the use of either an O.L.T.S. (Optical Loss Test Set) or and O.T.D.R. (Optical Time Domain Reflectometer).
The most accurate way of testing Optical Fibre is to inject a known level of light in one end and measure the level as it comes out the other end. Light sources and power metres (O.L.T.S.) are the main instruments recommended by the IEC to measure insertion loss.
Cable
Length is defined as the physical or sheath length of the cable. It should correspond to the length derived from the length markings commonly found on the outside jacket of the cable. Physical length is in contrast to electrical or helical length, which is the length of the copper conductors. Physical length will always be slightly less than electrical length, due to the twisting of the conductors.
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When current flows in a wire, an electromagnetic field is created which can interfere with signals on adjacent wires. As frequency increases, this effect becomes stronger. Each pair is twisted because this allows opposing fields in the wire pair to cancel each other. The tighter the twist, the more effective the cancellation and the higher the data rate supported by the cable.
FEXT
Far End Crosstalk is similar to NEXT, except that the signal is sent from a local end and Crosstalk is measured at the far end. Because of ATTENUATION, signals that induce FEXT can be much weaker, especially for longer cable lengths. This effect means that for a given quality of cabling, more FEXT will be seen on a short link than a long link. For this reason, FEXT results are not meaningful without an indication of the corresponding attenuation on the link. Thus, FEXT is measured but rarely reported. FEXT results are used to derive Equal Level Far End Crosstalk (ELFEXT).
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