2 – Infrastructure Flashcards
What is UTP?
Unshielded Twisted Pair • The most common type of copper cabling
In the context of cables, what is STP?
Shielded Twisted Pair • Provides additional shielding to protect against interference. • Requires the cable to be grounded, so a grounding wire is added to the groups of twisted pairs.
What is the standard and distance supported by this cable category? Cat 3
10BASE-T (10 Mb) 100 meters
What is the standard and distance supported by this cable category? Cat 5
100 Mb or 1000 Mb (100BASE-TX, 1000BASE-T) 100 meters
What is the standard and distance supported by this cable category? Cat 5e
100BASE-TX, 1000BASE-T (100 Mb or 1000 Mb) 100 meters
What is the standard and distance supported by this cable category? Cat 6
10GBASE-T 37-55 meters
What is the standard and distance supported by this cable category? Cat 6A
10GBASE-T 100 meters
What is the standard and distance supported by this cable category? Cat 7
10GBASE-T 100 meters
What is plenum-rated cable?
Meant for running through a plenum (a ceiling where airspace is circulating, which has fire-safety requirements). Typically not as flexible as regular PVC cable.
What types of Coaxial cables are there?
RG-6 • used in TV, digital cable, and high-speed internet over cable RG-59 • used as patch cables, not for long distances
What types of connectors are used with Coaxial cable?
BNC • Bayonet Neill-Concelman • Connector that you push in and twist to lock in place. • Often used in DS3 WAN links F-Connector • Often used with cable television / cable modem • Threaded connector, screws into place
What is a DB-25?
D-subminiature, or D-sub • “D” indicates shape of connector, B indicates size • 25 pins • DB-25 was one of the most popular serial connector types early on in computing. Not seen much today. • Often-color coded pink. • used for all kinds of different things: printing, modems, mice, networking.
What is a DB-9?
D-sub 9 • “D” indicates shape of connector, B indicates size • Technically, it’s properly a DE-9, since it is a size E D-sub rather than size B. • 9 pins • Can be color-coded green/teal. • Still seen today, often as a serial console interface for infrastructure devices
Single-mode vs. multimode fiber
Multimode • for short range, up to 2 km • uses an inexpensive light source, ex. LED • wider core, light disperses into multiple modes Single-mode • long range, up to 100 km • expensive light source; laser beams • narrow core, allows single mode of light
UPC vs. APC
UPC • Ultra-polished connector (or, Ultra-physical contact connector) • Ferrule end-face radius polished at 0 degree angle • high return loss (signal reflects back directly) APC • Angle-polished connector (or, Angled-physical contact connector) • Ferrule end-face radius polished at an 8 degree angle • Lower return loss (signal reflects back at angle, instead of back to source) • Higher insertion loss
What is an ST?
Straight Tip • Fiber connector • Round bayonet, push and twist to lock • long ferrule sticks out
What is an SC?
Subscriber Connector, or Standard Connector, or Square Connector • square shaped • round ferrule, but does not stick out as much as an ST conenctor • pushes into place, no lock
What is an LC?
Lucent Connector • aka Local Connector • “Little Connector” • smaller than SC, square shape, round ferrule that does not stick out much • locks into place with a tab like an RJ45
What is an MT-RJ?
Mechanical Transfer Registered Jack • smallest form of fiber connector • TX and RX fibers in the same form factor • Roughly same size as RJ45
When would you use a crossover cable?
When connecting “like” devices, such as switch-to-switch, or station-to-station. However, auto-MDX is enabled on most modern Ethernet devices. It examines the signal and automatically decides to use cross-over.
What is the order of colors for TIA/EIA 568A?
white / green green white / orange blue white / blue orange white / brown brown
What is the order of colors for TIA/EIA 568B?
white / orange orange white / green blue white / blue green white / brown brown
What is a 66 block?
• Type of patch panel • The left side is patched straight across to the right side • Often used in analog and voice connections, and old digital standards. • wires are punched into block
What is a 110 block?
• Designed to replace the 66 block • supports higher speed networks, Cat 5 and 6 cables • wires are punched into block, then connecting block is added on top of it, and additional wires are punched into connecting block • may have RJ45 connectors on the other side
What is a fiber distribution panel?
• Permanent fiber installation, with patch panels at both ends. • provides room for fiber to gentle loop around inside, since fiber does not have a tight bend radius.
What is a transceiver?
A device that is both a transmitter and a receiver, usually in a single component In networking, it usually refers to a modular interface. You can add whatever transceiver is needed into a slot on a switch.
What is a BiDi transceiver?
A Bi-Directional Transceiver • Supports traffic in both directions (TX and RX) within a single fiber, by using two different wavelengths.
What is a GBIC?
Gigabit Interface Converter • An early transceiver standard. • Commonly used on Gigabit and fibre channel networks. • both copper and fiber support • relatively large compared to newer standards of transceivers • effectively replaced by SFPs
What is an SFP?
Small Form-factor Pluggable • Commonly used to provide 1 Gbit/s fiber. Also available for copper (RJ45) • about 1/3 the size of the GBIC
What is SFP+?
Enhanced Small Form-factor Pluggable • Exactly the same form factor as SFPs • Supports data rates up to 16 Gbit/s • Common with 10 Gigabit Ethernet
What is a QSFP?
Quad Small Form-factor Pluggable • Effectively, 4 SFPs put into a single transceiver. • Only somewhat larger than one SFP. • 4-channel SFP = Four 1 Gbit/s = 4 Gbit/s • QSFP+ is 4-channel SFP+ = 40 Gbit/s • Also available to support BiDi on QSFP and QSFP+
What is a hub?
Operates at OSI layer 1, since no forwarding decisions are being made. • Operates at Half-duplex • Only at 10 Mb / 100 Mb speed • A hub is a “Multi-port repeater.” Any traffic going into one port is repeated to every other port.
What is this standard? 1000BASE-SX
Standard for Gigabit Ethernet over fiber • Uses NIR (Near infrared) wavelength • Usually multi-mode • Distance of 220 to 500 meters, depending on fiber type
What is this standard? 1000BASE-LX
Standard for Gigabit Ethernet over fiber • Uses long wavelength laser • Distance: - Multi-mode fiber for 550 meters - Single-mode fiber for 5 kilometers
Where are bridges still commonly found in networks today?
Wireless Access Points are bridges. They bridge wired Ethernet to wireless.
What is ASIC?
Application-Specific Integrated Circuit
What is a firewall?
At its most basic level, a firewall is a device that makes decisions on whether traffic is allowed or denied through the network based on Layer 4 information (such as a TCP or UDP port number). Though, modern firewalls can also make those decisions based on info as high as Layer 7. These may be referred to as “Next Generation” firewalls. Many firewalls can also function as a Layer 3 device (router) and as a VPN concentrator.
What is an AAA?
Authentication • Identify you, and prove you are who you say you are Authorization • Based on your identification and authentication, determine what access you are given Accounting • Record resources used, login time, data transmitted, etc. RADIUS is one of the more common AAA protocols.
What is RADIUS?
Remote Authentication Dial-In User Service • One of the more common AAA protocols. • Centralized authentication for users. • Can authenticate users to routers, switches, firewalls, etc. Can grant VPN access, server authentication, etc. • Available on almost any server OS.
What is UTM?
Unified Threat Management A device that performs several security services at the edge of a network. • URL filter / content inspection • malware inspection • spam filter • CSU / DSU It may also be a combined appliance that also provides: • firewall • VPN concentrator • router, swtich • IDS/IPS
What is an NGFW?
Next Generation Firewall Analyzes every packet and frame, and makes a security decision to allow or deny the traffic. Also called: • Layer 7 firewall • Application Layer Gateway • Stateful multilayer inspection • Deep Packet Inspection
What is the difference between a NAS and a SAN?
A NAS provides file-level access (if part of a file changes, the whole file must be saved and written. A SAN provides block-level access, very efficient with reading and writing.
What are Jumbo Frames?
• Six times the size of payload as a normal Ethernet Frame. • Normal Ethernet frames can support 1500 bytes of payload. • Jumbo frames can carry up to 9216 bytes of payload, but 9000 is the accepted norm since its more compatible with the 1500 size, as a multiple. • Using Jumbo frames increases transfer efficiency per packet size, since there are fewer packets to switch and route. • But for it to work, ALL devices on your network between you and the storage device must support Jumbo frames. The devices usually have an option that needs to be turned on.
What is FC?
Fiber Channel • A high-speed topology specifically built for Storage Area Networks (SANs). • Connects servers directly to storage devices, so they appear and operate as local disks. • Supports rates of 2, 4, 8, and 16 Gb/s • Supported over both fiber and copper • Requires an FC switch, and the server (initiator) needs a FC interface.
What is FCoE?
Fiber Channel over Ethernet • Use FC over an existing Ethernet network. • FC switch is not required. • Allows you to use the Ethernet card in a device, rather than an FC adapter/interface. • Since it is done at the Ethernet frame level, the traffic is not routable.
What is FCIP?
Fiber Channel over IP • Tunnels / Encapsulates FC data within IP packets. • Allows it to be routed to different IP subnets.
What is iSCSI?
Internet Small Computer Systems Interface • A type of SAN • Allows a remote disk to appear as, and operate as, a local disk. • Send SCSI commands over an IP network. • Not proprietary, no special hardware or interfaces needed, widely supported in software and many operating systems. • Since it uses IP, it is easily routable.
What is InfiniBand?
• A high-speed switching technology, and type of SAN • Designed for high speeds with low latency, common in research environments and supercomputers. • 100 Gb/s and 200 Gb/s are common. And, those links can then be aggregated together in 4x, 8x, and 12x links. • An alternative to Fiber Channel. • Uses its own specialized switches and adapter cards. • Allows connection to SAN using either copper or fiber, using QSFP connectors.
What types of SAN topologies exist?
Fiber Channel FCoE and FCIP iSCSI Infiniband
What is a CPE?
Customer Premises equipment The device that you connect to your side of the demarcation point. If its a tradition T1 or T3 connection, your CPE may be a CSU or DSU.
What is Split horizon?
Split horizon is a method of preventing a routing loop in a network. • It follows this basic principle: Information about the routing for a particular packet is never sent back in the direction from which it was received. • Split-horizon route advertisement is a method of preventing routing loops in distance-vector routing protocols by prohibiting a router from advertising a route back onto the interface from which it was learned.
What is Persistent MAC learning?
Persistent MAC learning, also known as Sticky MAC, is a port security feature that enables an interface to retain dynamically learned MAC addresses when the switch is restarted or if the interface goes down and is brought back online. This can be used to prevent someone from unplugging their office computer and connecting their own laptop to the network jack without permission, since the switch port connected would only allow the computer with the original MAC address to gain connectivity.
What is Sticky MAC?
Persistent MAC learning, also known as Sticky MAC, is a port security feature that enables an interface to retain dynamically learned MAC addresses when the switch is restarted or if the interface goes down and is brought back online. This can be used to prevent someone from unplugging their office computer and connecting their own laptop to the network jack without permission, since the switch port connected would only allow the computer with the original MAC address to gain connectivity.
What is: SCADA
Supervisory Control and Data Acquisition
What is: ICS
Industrial Control System or, possibly, Internet Connection Sharing
What is: IS-IS
Intermediate System to Intermediate System
What would this type of network be used for? SCADA/ICS
SCADA/ICS is used in industrial control systems, such as an assembly-line network.
What is: DWDM
Dense Wavelength-Division Multiplexing • a high-speed optical network type commonly used in MANs (metropolitan area networks). • DWDM uses as many as 32 light wavelengths on a single fiber, where each wavelength can support as many as 160 simultaneous connections.
What types of connectors are used with Twister Pair cables?
RJ-45 RJ-11 DB-9 DB-25
What are the pros and cons of fiber, when compared to copper?
Pros: • much higher bandwidth • much longer distances • immune to EMI • better security, more difficult to tap Cons: • significantly more expensive • more difficult to install
What is DOCSIS?
Data Over Cable Service Interface Specification A standard that permits the addition of high-bandwidth data transfer to an existing cable television system. Most people today call these ‘cable modems’, but technically they are DOCSIS modems.
What is DSL?
Digital Subscriber Line High-bandwidth data connection over ordinary copper telephone lines.
What is PSTN?
Public Switched Telephone Network The world’s collection of interconnected voice-oriented public telephone networks
What is this? RG-59
A type of coaxial cable. Used as patch cables. Not designed for long distances.
What is this? RG-6
A type of coaxial cable. Used in TV, digital cable, and high-speed internet over cable. Longer distances than an RG-59.
What connectors are possible for Fiber cables?
ST SC LC MT-RJ
What is: MPLS
A type of data-carrying technique that enables use of different types of network protocols on the same network is known as Multiprotocol LabelSwitching (MPLS)
What is: Smart Jack
A device providing remote line diagnostics capability placed at the joining point between an ISP’s line and customer’s premises wiring is known as smart jack.
a straight-through cable is used to:
connect a host to a switch or hub,
or a router to a switch or hub
A crossover cable is used to connect the following:
Switch to switch
hub to hub
hub to switch
host to host
router direct to host
a rollover cable is used for:
a host to interface with a router or switch’s console COM port
A MDF is:
- Main disribution frame, a wiring point that is primarily used as a reference point when it comes to telephone line.
- it can also be considered a Wan termination point.
- It is installed in the building during the prewiring phase and all the internal lines are then connected to it.
What would happen regarding the difference in length of wire pairs for UTP
As the number of twisted pairs goes up, the possible length of the wire shortens due to signal degradation. Because of this, cables that have fewer twists can extend father, and high-twist cables need to be repeated sooner.
Advantages and disadvantages of F/UTP:
Foiled/unshielded twisted pair is an enhanced version of cable that has a metal foil rolled into hte design. This enables it to completely resist RFI and EMI interference, as well as blocking the ability to catch signal leakage from the cable and eavesdrop on the network.
what is topology?
A network topology, like a topological map, displays the physical configuration of the network, such as where hosts and switches are placed and the connections between them.
Star Network:
in a star network, each node is connected to a central point, with direct connections between the host and the switch or hub. In this way, if a node fails it can be easily fixed, but if the hub or switch fails, it will take down the network
a bus topology
a contiguous wire that is terminated at each end with each node plugged into the wire
a ring topology
a network where each node is connected to the next node, forming a circular network
Difference hub vs switch:
hub: capable of connectng network segments and host to the rest of network
replicate data to its port,causing collision if two computer sending traffic the same time
Switch: individual collision domain for each port, negating this issue
First thing to do when designing an office LAN network
Documenting and enumerating all devices to be connected
It is important to know what devices are going to be connected to the network so that you understand what the needs of the network will be. Without this understanding, it is possible to configure a network that is inadequate and prone to failure in certain environments. Furthermore, without proper planning and documenting of said planning, troubleshooting, repairing and replacing the network in the future becomes much more difficult.
Maximum length of a UTP cable:
100 meters.
STP characteristic
Shielded twisted pair has foil intertwined with twisted pairs of wire. It is this foil that provides the ability to block EMI from the environment and actually makes it an excellent wire for EMI-prone offices.
What is EMI
Electromagnetic Interference (EMI). Insulation protects a cable from mechanical abrasion, environmental moisture and spills.
Crimping tool
a crimping tool is used after the wires are inserted into a wire jack such as an RJ45 connector. the crimper tool pushes the metal contact into the wire and sets it permanently
tools used for making UTP cables
Strippers and crimpers. Strippers are used to cut twisted pair wire and attach it to the intended connector.
hoAn RJ 45 modular plug has how many pins?
An RJ 45 modular pulg has 8 pins. Following the T565B standard
Wavelength of multimode fiber
850nm tand 1300 nm
fiber architecture
Fiber architecture is currently designed to provide architecture such as :
fiber to the curb,business, home.
However, it has not gotten to the point where fiber optical cable goes directly to workstations. Typically, it’s connected to the larger location as a whole, such as the home or business, then UTP,STP or wireless connections are used to connect to the fiber endpoint.
WAN link
a connection for a network to forward data over long distance
NaaS
Network as a Service is used when having an on-premise network and staff is not feasible for a company. Cisco offer a service called OpenStack, which is a cloud service that provides virtualization of network resources.
HaaS
a Hardware as a Service, in which leasable hardware components are utilized
SaaS
software as a Service, in which a company offers software such Microsoft Office as a service in the cloud
PaaS
Platform as a Service, in which providers enable developers to launch code and use computing platforms such as web servers or deployment points.
IaaS
Infrastructure as a Service is where the provider makes a hardware platform or data center available to a customer. The customer is the nable to install their own operating system and applicaitons
CO
a central office is a telephone company’s phone switching equipment location
Access point
an access point is used in wireless networks and provides a point for wireless clients to connect to
Patch panel
a wiring closed will have one or more patch panels into which cables come and terminate into a familiar RJ 45 female jack. With many cables being run throughout the are. This makes it much easier to label, control and roubleshoot.
A
to map a hostname to an IPV4 address, an (A)address record is used
AAAA
an address record AAAA is the IPV6 version used to map an IPV6 address to a hostname
SOA
A start of authority SOA record provides authoritative information about a DNS zone
MX
A mail exchange record is used to map a domain name for use in an email server
CNAME
a CNAME record is used to add hostnames to already established www hostnames. For example, adding an “ftp.company.com” domain name to “www.company.com”
DHCP lease,scope,reservation,option
A DHCP lease is a temporary assignment of IP address information to a DHCP client. DHCP scope is the pool of IP addresses used by a DHCP server to assign IP addresses to DHCP clients. A DHCP reservation is tying a specific IP address to a specific MAC address. A DHCP option is used to assign IP address parameters.
ST
SC / LC . ST / MT-RJ
eight-pin connector used most often in Ethernet networks
RJ-45, The RJ-45 connector is the most ubiquitous connection for Ethernet, especially in the home. Store-bought Ethernet cables come with the connector, though it is possible to make your own when purchasing the cable and connectors in bulk
RJ-45 used in:
Ethernet, nearly all computers laptops and desktops
serial port
RJ-11
the primary connector to te phone and to the wall
ISDN
integrated Service Digital Network is a point-to-point WAN technology that is an example of circuit switched WAN technologies
ATM
Asynchronous Transfer Mode, considered a cell switched technology.
Packet switching
a method of grouping data that is transmitted over a digital network into packets which are made of a header and a payload
Frame relay
packet switch technology
Circuit switch example
ISDN
ISDN circuits are classified as:
BRI basic rate interface circuit or PRI, primary rate interface.
BRI contains:
two 64kbs B channels and one 16 kbps D channel.
PRI contains:
PRI builds on T1 or E1 circuit
NT1
a device that connects a 4-wire ISDN circuit with a 2-wire ISDN circut
TA
A terminal adapter used in ISDN networks for clients to connect to the network
TE1
a device natively support ISDN
CSU/DSU
When using a dedicated leased line, the connection that comes into the location will be terminated on a device called the channel service unit/data service unit(CSU/DSU), Leased lines commonly use the layer 2 protocol, point to point protocol(PPP).
CSU/DSU usually use ___ connector
RJ-48C
PPP
a data link layer protocol that can be used over asynchronous serial(dial-up) or synchronous serial(ISDN), It’s a non-proprietary protocol and is primarily designed to transport Layer 3 packets over the data link layer.
T3
like t1, example of leased line network. ISDN is circuit switched
OC 1,3,12,48,192 speed
OC1 51.84M
OC3,155.52M
OC-12 622.08M
OC48 2.488G
OC-192-9.953G
smart jack
a type of network interface device that adds circuitry, this circuitry adds such features as converting between framing formats on a digital circuit (t1), supporting remote diagnostics and regenerating a digital signal
Demarcation point
the point a telephone network where the maintenance responsibility passes from a telephone company to the subscriber.
NID
network interface device, a box mounted outside customer’s building for Demarc
tip and ring wires
red and green wires found in an RJ-11 wall jack, which carry voice ,ringing voltage and signaling information between an analog device
E1
European version of the T11 connection and operates at 2.048 Mbps using thirty-two 64kbs channels, with tirty avalable for data , voice, or video
E3
European version of t3, 34.368, whereas T3, hs 44.736.
T3 has 28T1 connections, E3 has only 16 E1.
DOCSIS
The Data-Over-Cable Service Interface Specification identifies the frequencies dedicated to data transmission and handling.
TDM
ime division multiplexing is a technology that enables multiple transmissions to share the same medium.
HFC
A hybrid fiber-coaxial network is how cable companies provide high-speed transmission to specific locations before it is broken down into a slower speed coaxial configuration.
DSLAM
A DSL access multiplexer is a device that terminates multiple DSL connections from customers.
DLCI
A Data link Connection Identifier is used in a frame relay network to distinguish between virtual circuits. Many DLCIs can be associated with one frame relay interface. It is this property that enables frame relay configurations to save over individual leased lines because it can break the connections into multiple circuits.
PAP
password authentication protocol, is the least secure option when it comes to PPP authenticatin methods. With PAP, the credentials are passed in clear text between the client and the remote node, which makes it rather easy to eavesdrop.
CHAP
Challenge Handshake Authentication Protocol(CHAP) is more secure because it provides secure authentication via a one-way hash mechanism.
ATP
The asynchronous Transfer Mode is a high-speed communications protocol that can handle real-time voice and video transmissions. The AATM protocol breaks up data into 53-byte cells. Though packets and frames can vary in size. ATM’s cells are always 53 bytes with 48 bytes of payload data.
payload data size of ATM
48 bytes
What do you use to connect the smart jack to CPE
Demarc extension, a demarc extension is the transmission path originating from the interface of the access provider’s side of a telecommunications circuit demarcation point within the premises and ending at the termination point prior to the interface of the edge of the Customer Premises Equipment(CPE).
The term Asmmetric DPS means:
it means the download speeds and uploads speeds are different. This provides higher downstream speed with the sacrifice of upstream speed. The typical consumer perceives it as a huge boost in speed due to the fast download rates.
speed of T1 T3
T1 and E1 : 1.544 and 2.048
T3 and E3: 44.7 and 34.368
banthwave capacity of T4:
274.176M
size of MPLS
32
XDSL with highest bandwidth:
VDSL, 52m downstream and 12M upstream
best option for remote locations that have limited WAN connectivity choices?
Some location might be able to connect the internet, or to a remote office using satellite communications, where a transmission is bounced off of a satellite, received by a satellite ground station, and then sent to its destination using either another satellite hop or a wired WAN connection
Cable modems are usually connected viaL
an F-Connector attached to an RG-6 coaxial line
Network connection via UTP
ISDN DSL and dial-up modem, typically with an RJ-11
WiMAX
Worldwide interoperability for Microwave Access provides wireless broadband acess to fixed locations(as an alternative to technologies such as DSL) and mobile devices, WiMAX could cover the entire city
HSPA+
a technology offering wireless broadband service. The maximum data rate for HSPA+ is 84M. The highest data rates come form LONG TERM EVOLUTION(LTE) with reliable speeds and compatibility with WIMAX and 3G
The frequencies dedicated to data transmission are specified by?
DOCSIS
Virtual private branch exchange:
usually a voice over internet protocol solution, where voice is encapsulated inside data packets for transmission across a data network.
Where a SaaS solution application locates at
offsite
EDNS
Extension Mechanisms for DNS, supports features not supported in the original version of DNS while maintaining backward compatibility with the original version of DNS. Rather than using new flags in the header, which would impact backward compatibility, EDNS sends optional pseudo-resource records between deveices uspporting EDNS.
