Technologies You Should Know to Get a Networking Job - dummies

Technologies You Should Know to Get a Networking Job

By Peter H. Gregory, Bill Hughes

To get a networking job, you need to know the current technologies in use. As with any technology-related field, the tools of the trade are constantly changing as new technologies emerge and others become obsolete.

Wired telecom network technologies

Wired telecom networks connect homes, businesses, schools, and governments through technologies that use copper or fiber optic cabling to carry many types of signals. These signals include the following:

  • DS-1 (Digital Signal one), T-1, E-1: DS1 is a family of multiplexed telecommunications technologies that have carried voice and data for decades in the United States and Europe. In the United States, T1, which runs at 1.544Mbps, is the basic protocol. It’s often multiplexed into 24 64Kbps voice channels for use by ordinary phone and fax lines, often known as POTS (plain old telephone service). In Europe, E1 is the basic protocol, at 2.048bps, or 32 voice channels. Speeds higher than DS-1 are available, such as DS-3 (44.736Mbps), DS-4 (274.176Mbps), and DS-5 (400.352Mbps).

  • SONET (Synchronous Optical Networking): This new high-speed telecommunications backbone technology runs over fiber optic cables on land and in submarine cables. SONET runs at dizzying speeds, including OC-1 (48.960Mbps), OC-3 (150.336Mbps), OC-12 (601.344Mbps), OC-96 (4,810.752Mbps), and OC-192 (9,621.504Mbps).

  • DSL (Digital Subscriber Line): This family of protocols is delivered to homes and businesses over the same pairs of copper wires as telephone service but at a higher frequency.

  • DOCSIS (Data Over Cable Service Interface Specification): This family of technologies transports TCP/IP over cable television service to homes and businesses.

  • MPLS (MultiProtocol Label Switching): This packet-switched technology transports a variety of protocols such as TCP/IP, Ethernet, ATM, and VoIP over long distances. MPLS includes Quality of Service (QoS) settings to ensure that protocols such as voice and streaming video are transported without annoying interruption even when networks are congested.

  • Dark fiber: This option is not a technology but a telecommunications medium available to businesses. Businesses can connect their own telecom equipment to fiber optic cabling to connect their networks between buildings in a city or metropolitan area, using any protocol they want.

Older technologies you don’t need to be too concerned with anymore (unless you’re a technology history buff) include ISDN, ATM, frame relay, X.25, and PSTN.

Wireless telecom network technologies

Wireless telecom networks connect individuals, homes, and businesses through the use of several technologies, including the following:

  • GPRS (General Packet Radio Service): This technology is encapsulated in the GSM (Global System for Mobile communications, originally Groupe Spécial Mobile) cellular protocol.

  • LTE (Long Term Evolution): This wireless telecom standard provides voice and data service with speeds up to 300Mbps.

  • WiMAX (Worldwide Interoperability for Microwave Access): A wireless telecom standard that provides data rates up to 40Mbps for mobile stations and 1Gbps for fixed stations, WiMAX was developed as a wireless alternative to DSL and DOCSIS.

Other notable technologies include CDPD, CDMA, and packet radio.

Wired consumer and business network technologies

Although many standards have been used for wired network technologies, the long-term trend has been a general migration to TCP/IP on Ethernet over copper cabling or fiber optic cabling. The dominant technologies follow:

  • CAT-6 (Category 6) cabling: The darling of homes and businesses running wired networks over distances of up to 100 meters, CAT-6 cabling can run Ethernet speeds up to 10Gbps.

  • Fiber optics: Businesses often run fiber optics in larger buildings to connect networks from floor to floor, as well as from building to building. Fiber-optic cabling is made of glass and transmits signals as visible light, as opposed to CAT-6 and other metallic cabling, which transmit data as electrical signals.

Has-been cabling used in the past include Thinnet, Thicknet, Cat-3, and Cat-5.

Wireless consumer and business network technologies

Wireless network technologies are wildly popular in a number of typical settings. The technologies in use are

  • Wi-Fi: The IEEE 802.11 family of wireless protocols are widely used in small and large residences, businesses, retail stores, restaurants, government buildings, and even outdoors. A variety of security protocols are used on Wi-Fi, ranging from none (no encryption), WEP (Wired Equivalency Protocol, considered obsolete), WPA (Wireless Protected Access, which is just okay), and WPA2 (preferred by anyone thinking about security). The range of Wi-Fi is about 20 meters indoors and farther outdoors.

  • Bluetooth: This popular wireless protocol connects devices in close proximity. Wireless earsets and headsets were the first popular use of Bluetooth.

  • NFC (Near Field Communications): This very short-range (6 cm) wireless protocol was developed for use in contactless payment systems.

Runner-ups include iRDA (the infrared point-to-point technology, which has all but disappeared) and wireless USB (up and coming, and possibly a force in the future).

Software-defined networking (SDN)

Software-defined networking is an emerging technology that is simplifying network architectures and helping to reduce costs. Instead of purchasing a lot of separate specialized network devices such as load balancers, web application firewalls, intrusion prevention systems, routers, and switches, organizations can purchase a few OpenFlow-enabled switches and a centralized controller, and then build a network fabric that exists virtually in the switch, performing all those functions in harmony instead separately.

Currently, 90 percent of IT workers (including a lot of senior-level people) don’t understand SDN, so you should consider this a ground-floor opportunity. If you’re fortunate enough to get some SDN training or work alongside someone who is doing SDN, stay with it as long as you can.