Networking ch3 Flashcards
Coax Cable
composed of 2 conductors an inner insulated conductor and another inner isolated conductor inside the first. the second is occasionally made of metallic foil or woven wire.
Twisted-Pair Cable
individually twisted copper strands and intertwined within. the 2 categories are Shield Twisted Pair (STP) and Unshielded Twisted Pair (UTP)
Shield Twisted Pair Cable (STP)
defined by the IEEE 802.ID standard, it allows a network to have redundant layer 2 connections, while logical preventing a loop, which could lead to symptoms such as a broadcast storms and MAC address table corruption
Unshielded Twisted Pair Cable (UTP)
blocks EMI from the copper strands making up a twisted pair cable by twisting the strands more tightly (that is more twists per cm) by wrapping these strands around each other, the insulate each other from EMI
Electromagnetic Interface (EMI)
an electromagnetic wave form that can be received by network cable (possibly corrupt data traveling on the cable) or radiate from the network cable (possibly interfering with the data traveling to another cable)
Plenum
cabling that is fire retardant and minimizes toxic fumes released by network cabling if cabling were on fire. often required by local fire codes for cable In raised flooring or in an open air return duct
Multimode Fiber (MMF)
has a core with a diameter large enough to permit the injection of light into the core at multiple angles. the different paths (modes) the light travels can lead to multimode delay distortion, which causes bits to be received out of order
Single-Mode Fiber (SMF)
diameter is only large enough to permit a single path of light to pulse(only one mode of propagation) eliminates the concern of multimode delay distortion
66 Block
traditionally cross-connects phone system cabling in corporations. also cross connect cat 3 UTP cabling. do not support LAN speed over 10-mbs
110 Block
because 66 blocks are subject to too much crosstalk for higher speed LAN connections, this can be used to terminate a cable (such as a cat 5 cable) being used for those higher-speed LANs
Hub
older, used to interconnect network components like clients and servers. vary in number of available ports. do not preform any inspection of traffic, simply receives traffic in a port and repeats to all other ports
Switch
interconnects network components. vary in number of available ports. learns which devices reside out of which port. traffic is inspected and sent to appropriate port instead of all other ports
Router
a layer 3 device. makes forwarding decisions based on logical network addresses. most modern networks use IP addressing have greater feature sets and are capable of supporting more interface types than a multilayer switch
Multilayer Switch
can make traffic based decisions on layer 3 info. they more closely approach wire-speed throughput tan most routers.
Firewall
network security appliance. can protect a trusted network (EX. corporate LAN) from an untrusted network (EX. the internet) by allowing the trusted network to send traffic into the untrusted network and receive the return traffic for untrusted, while blocking traffic for sessions initiated by untrusted network
Domain Name System Server (DNS)
takes a domain name and resolves that name into a corresponding IP address
Dynamic Host Configuration Protocol (DHCP)
dynamically assigns IP address info (EX. IP address, subnet mask, DNS servers IP address, default gateways IP address) to network devices
Proxy Server
intercepts requests from client and forwards to intended destination. then it sends any return traffic back to client who initiated session. this provides address hiding for the client. some conserve WAN bandwidth by offering content catching function. some offer URL filtering (EX. block social media sites of users during work hours)
Content Engine
dedicated appliance whose roll is to logically cache content received from a remote network (EX. destination on internet) subsequent requests for that content can be served logically, from the content engine, reducing bandwidth demand on a WAN
Content Switch
load balance requests for content across a group of servers containing that content. if one server in a group needed maintenance preformed that server could be administratively removed from the group, maximizes up time when preforming service maintenance. minimizes load on individual serves by distributing its load across multiple identical servers. also allows a network to scale, because one or more servers could be added to the server group defined on the content switch, if the load on existing serves increases
Virtual Server
allows a single physical server to host multiple virtual instances of various operating systems. EX. a single physical server could host multiple Microsoft windows servers and multiple Linux servers
Virtual Switch
preforms layer 2 functions (EX. VLAN separation and filtering) between various server instances running on a single physical server
Virtual Desktop
allows a user to store data in a centralized data center, as opposed to a hard drive or local computer. with appropriate authentication a user can access the data from various remote devices. (EX. smart phone, other computer)
On-Site
In the context of virtualization technologies refers to hosting virtual devices on hardware physically located in a corporate data canter
Off-Site
in the context of virtualization technologies refers to hosting virtual devices on hardware physically located in a service providers data center
Network as a Service (NaaS)
a service provider offering were clients can purchase data services (EX. email, LDAP and DNS services) traditionally hosted in a corporate data canter
Virtual PBX
usually a VoIP telephony solution hosted by a service provider, which interconnects with the company’s existing telephone system
Session Initiation Protocol (SIP)
a VoIP protocol used to set up, maintain and tear down VoIP phone calls
Real-Time Transport Protocol (RTP)
a layer 4 protocol that carries voice (and interactive video)
