Tuesday, 26 February 2013

Cables Part 2

Posted by Puneet Sharma on 17:45 Networking No comments

Co-Axial Cable:

It carries signals of higher frequency ranges than those in twisted pair cable.
Data is transferred in the form of electrical signals.
BNC(British Novel Connector) connector is used to join two co-axial cables.
It consist of central core conductor enclosed in an insulating sheath than outer conductor(shield) which is also enclosed in an insulating sheath and then whole cable is protected by a Plastic cover.
It was widely used in analog telephone networks where a single coaxial network could carry 10,000 voice signals.
Types: Thick-net(10Base5 where speed is 10Mbps and segment length with range of 5000m with Baseband) & Thin-net(10Base2 where speed is 10Mbps and segment length with range of 185m with Baseband)
Categories:

Fiber-Optic Cable:

A fiber-optic cable is made of glass or plastic and transmit signals in the form of light signals.
Transfer Rate is very high about 10Gbps.
Segment Length is in KMs.
It consist of outer jacket made of PVC or TEFLON. Inside the jacket are Kevlar(used in the fabrication of bulletproof vests) strands to strengthen the Cable.
Fiber is at the center of the cable & it consists of cladding and core.
Fiber-optic cable is often found in backbone networks because its wide bandwidth is cost-effective.
Some cable TV companies use a hybrid combination of optical fiber and coaxial cable.
LANs such as 100Base-FX network(Fast Ethernet) & 1000Base-X also use fiber-optic cable.
Fiber Types:

50/125 : Core(50.0μm), Cladding(125μm),Mode= Multi-mode,graded Index.

62.5/125 :Core(62.5μm), Cladding(125μm),Mode= Multi-mode,graded Index.

100/125 :Core(100.0μm), Cladding(125μm),Mode= Multi-mode,graded Index.

7/125 :Core(7.0μm), Cladding(125μm),Mode= Single mode.

Propagation modes:

Single Mode:

It uses step-index fiber and a highly focused source of light that limits beams to a small range of angles,all close to the Horizontal.
Only one glass rod is used.
Data is sent in Half Duplex Mode.
Propagation of beam is almost Horizontal.

Multi-Mode:

Multiple glass rod is used.
Data is sent in Full Duplex Mode.
In Multi-mode step index fiber, the density of the core remains constant from the center to the edges.
In Multi-mode graded-index fiber, decreases the distortion of the signal through the cable.

Connectors:

Three types of connectors for fiber-optic cables:-

Subscriber Channel(SC) connector: It is used for cable TV & uses a push/pull locking system.
Straight-Tip(ST) Connector: It is used for connecting cable to networking devices & it uses a bayonet locking system & is more reliable than SC.
MT-RJ: It is a connector i.e the same size as RJ45.

Advantages:

Disadvantages:

Rollover Cable:

It is used in configuration i.e for configure Firewalls etc.
It can't be connected in LAN card.
It is connected in COM 9 of PC to Console Part of Router/Switch/Firewall.

Made By: P & V