OBJ 1.2 X Flashcards
Mesh
each device has (in theory) a point-to-point connection with every other device (fully connected);
Star/hub and spoke
STAR Most popular physical LAN topology
▪ Devices connect to a single point
▪ Commonly used with Ethernet cabling, but wireless or fiber is also used
▪ If the central device fails, the entire network fails
HUB AND SPOKE
▪ Used for connecting multiple sites
▪ Similar to Star but with WAN links instead of LAN connections
▪ Not redundant, if central office (hub) fails, the whole network can fail
Bus
Uses a cable running through area that required network connectivity
▪ Each device “taps” into the cable using either a T connector or vampire
tap
▪ Old technology, not commonly used anymore
▪ Devices on cable form single collision domain
Ring
▪ Uses a cable running in a circular loop
▪ Each device connects to the ring, but data travels in a singular direction
▪ FDDI (Fiber networks) used two counter-rotating rings for redundancy
▪ On token ring networks, devices wait for a turn to communicate on ring
by passing a token
Hybrid
Partial-Mesh Topology
▪ Hybrid of the full-mesh and the hub-and-spoke topologies
▪ Provides optimal routes between some sites, while avoiding the expense
of connecting every site
▪ Must consider network traffic patterns to design it effectively
Peer-to-peer
Peers (PCs) share resources (files/printers) with each other directly
Administration and backup are more difficult since resources are located on a many PCs which adds to the administrative burden
Benefits of Peer-to-Peer
▪ Lower cost
▪ No dedicated resources required
▪ No specialized operating system required
Drawbacks of Peer-to-Peer
▪ Decentralized management
▪ Inefficient for large networks
▪ Poor scalability
Client-server
▪ Uses dedicated server to provide access to files, scanners, printers, and other resources
Administration and backup are easier since
resources are located on a few key servers
Benefits of Client/Server
▪ Centralized administration
▪ Easier management
▪ Better scalability
Drawbacks of Client/Server
▪ Higher cost
▪ Requires dedicated resources
▪ Requires network operating system
LAN
▪ Connects components in a limited distance
▪ Each segment is limited to short distances, such as 100 meters with CAT 5 cabling
▪ Consists of Ethernet (IEEE 802.3) or WiFi networks (IEEE 802.11)
● Internal wired or wireless networks
MAN
Connects scattered locations across a city
▪ Larger than a CAN, but smaller than a WAN
▪ Covers up to a 25-mile radius in larger cities
▪ Examples:
● City departments like the police department
● Community college with campuses spread across a county
WAN
▪ Connects geographically disparate internal networks
▪ Consists of leased lines or Virtual Private Networks tunneled over the
Internet
▪ Covers distances around the country or around the world
Examples:
● The Internet (largest WAN)
● Connecting two private corporate networks from New York to
Seattle
WLAN
▪ Smallest type of wired or
wireless network
▪ Covers the least amount
of area (few meters)
▪ Examples:
● Bluetooth cellphone to car
● USB hard drive to laptop
● Firewire video camera to
computer
PAN
▪ Smallest type of wired or
wireless network
▪ Covers the least amount
of area (few meters)
▪ Examples:
● Bluetooth cellphone to car
● USB hard drive to laptop
● Firewire video camera to
computer
CAN
Connects building-centric LANs across a university, industrial park, or
business park
▪ Covers many square miles and buildings
▪ Examples:
● College campus
● Business Parks
● Military bases
SAN
● Specialized LAN designed for data transfer/storage
● Transfers data at block level with special protocol
SDWAN
Software-Defined Wide Area Network (SDWAN)
▪ A virtual WAN architecture that allows enterprises to leverage any
combination of transport services to securely connect users to their
applications
▪ Uses a centralized control function to securely and intelligently redirect the traffic across the WAN
▪ Enable cloud-first enterprises to deliver quality experiences to their users
▪ Allows your WAN environment to be more dynamic and efficient
▪ Reduces bottlenecks caused by your traditional, centralized WAN
architecture
MPLS
“Layer 2.5” network protocol used by service providers to implement WAN access links and virtual private networks with traffic engineering (congestion control), Class of Service, and Quality of Service.
mGRE
Multipoint generic routing encapsulation. A protocol that can be used to enable one node to communicate with many other nodes, essentially creating a point to multipoint link
▪ NOT limited to point to point connections
▪ Usually combined with the Dynamic Multipoint VPN, or DMVPN,
protocol, as well, for security
Demarcation point
The entrance facilities where you WAN connection will enter your building.
vSwitch
Overcomes the problem of
all virtual servers being on
one broadcast domain
▪ Layer 2 control provides
VLANs and trunking
▪ Provides Quality of Service
and security
Satellite provider link
o Used for remote areas
o Flying and Shipboard use
o Expensive in comparison to cellular, cable, or fiber
connections
DSL (Digital Subscriber Line) provider link
Asymmetric DSL (ADSL)
● Maximum distance to DSLAM: 18,000 feet
● Voice and Data on same line
● Downstream: Up to 8 Mbps
● Upstream: Up to 1.544 Mbps
▪ Symmetric DSL (SDSL)
● Maximum distance to DSLAM: 12,000 feet
● No simultaneous voice and data on same line
● Downstream: 1.168 Mbps
● Upstream: 1.168 Mbps
▪ Very High Bit-Rate DSL (VDSL)
● Maximum distance to DSLAM: 4,000 feet
● Downstream: Up to 52 Mbps
● Upstream: Up to 12 Mbps
Leased line provider link
▪ Logical connection that connects two sites through a service provider’s
facility or telephone company’s central office
▪ More expensive than other WAN technologies because a customer
doesn’t share bandwidth with other customers
