3. Networking and Communication Basics Flashcards
is defined as two or more objects sharing resources and
information,
computer network
A network can be classified into two major geographic categories:
local area network
LAN) and wide area network (WAN
is a small area networked with a series of cables or wireless access points that allow computers to share information and devices
on the same network.
local area network (LAN)
These are the least expensive to install, and they are much faster than WAN because of their smaller size
local area network (LAN)
has the fastest communication technology because less equipment and fewer resources are needed to complete the network
local area network (LAN)
The picture archival and communication system (PACS) workstations in a radiology reading room would be considered a ____
LAN
Generally the larger networks are composed of several LANs interconnected to
create the ____
WANs
is a network that spans a large area: city, state, nation, continent, or the world
wide area network (WAN)
It is used to connect computers that are not physically attached through conventional network cables but are rather connected through other means, such as telephone lines, satellite links, or other types of communication cable
Wide Area Network (WAN)
each computer on the network is considered equal; no computer has ultimate control over another. Each computer controls its own information and operation and can function either as a client or as a server depending
on the needs of the other computers on the network.
Peer-to-Peer Network
is most popular in small office or home network configuration because it is the least expensive and most simple to set up
Peer-to-Peer Network
has a limited scope because the maximum number of peers that should be connected is 10. More than 10 causes bottlenecks and collisions on the network.
Peer-to-Peer Network
there is a centralized computer that controls the operations, files, and sometimes the programs of the computers (the clients) attached to the network.
Server-Based Network
is similar to a server-based network in that there is a
centralized computer that controls the operations of the network
client-based network
rather than sending the entire original resource to the client for processing, the server processes the resource as requested by the client and returns only the results back to the
client
client-based network
is a computer that manages resources for other computers, servers, and
networked devices
server
It may also house applications, provide storage for files, or manage various other networked tasks.
server
is most often dedicated to one task for the
network and is usually the most robust computer on the network.
server
is a device that is found on a network that requests services and
resources from a server
thin-client
may be another computer, a printer, or any other networkable device that needs a server to complete its tasks
thin-client
Almost any personal
computer (PC) can be a ____, as long as it can be attached to the network.
client
is a computer that can work independently of the network and
process and manage its own files
thick-client
is networked so that it can share resources such as printing and take advantage of the additional security available on
networks through dedicated servers
thick-client
is generally a high-end computer
that does high-level processing for specific purposes
thick-client
In health care, specialty application workstations (____) are most often found in cross-sectional imaging
modalities for which three-dimensional imaging is used to aid diagnosis.
thick-client
is similar to the wiring used for the cable television
that is run into a house
Coaxial cable
This type of cable consists of a center conducting wire surrounded by insulation and then a grounded shield of braided wire.
Coaxial cable
is the sturdiest wire
used and is often found in the network infrastructure throughout a building.
Coaxial cable
It is often connected to another type of communication medium before it meets the device
interface.
Coaxial cable
is similar to telephone wire, but whereas telephone wire has only four wires, it usually consists of four twisted pairs
of copper wire that are insulated and bundled together with an RJ-45 termination
Twisted-pair wire
comes in various levels of quality and capacity
Twisted-pair wire
It is the most commonly used
connection medium in LANs
Twisted-pair wire
The minimum standard of twister-pair wire is
Cat 5 (category 5) cable
uses glass threads to transmit data on the network
Fiberoptic cable
It consists of a fiberoptic core that is surrounded by a plastic protective covering
Fiberoptic cable
It is much faster than its metal counterparts, but it is more expensive and much more fragile. It can easily be damaged by kinking and twisting the cable
Fiberoptic cable
It is
most often used in the infrastructure of the network, in network closets, and in large
archive/computer rooms
Fiberoptic cable
are becoming more commonplace as technology continues to improve
Wireless connections
The connection is made by using either infrared or radio
frequencies as its means of communication
Wireless connections
There is no physical cabling needed, but
each device must contain the appropriate wireless transmitter/receiver
Wireless connections
The biggest
advantage of wireless connections is ____ and _____, but it has a ____ range.
mobility,
convenience,
limited
Devices other than computers can also be found on a _______, such as printers, scanners, and barcode readers.
network
provides the interface between the
computer and the network medium; it provides the physical connection between the network and computer.
network interface card (NIC)
works with networking software to establish and manage the data, to chop up the data into packets, and to handle addressing issues.
network interface card (NIC)
is the simplest device that can be used to connect several pieces of
equipment together for network communication purposes
Network Hub
It has several wiring ports
available on it to receive and transmit data to the various connected pieces of equipment.
Network Hub
are commonly used in small office and home applications
Hubs
is similar to a hub, but it sends data only to those devices to which
the data are directed.
Network Switch
It will read the destination address from the data and select a
direct path to the intended target.
Network Switch
This reduces the network traffic, speeds up the
overall network connection, and makes the network more efficient.
Network Switch
is sometimes created so that larger networks can be segmented or
broken up into smaller networks to reduce traffic within that network.
Network Bridge
is a physical (wired) connection from
one network segment to another.
The bridge
It can recognize in which segment a particular destination address resides and send data to it.
The bridge
It can recognize in which segment a particular destination address resides and send data to it.
The bridge
is a more sophisticated device
Network Router
It can read portions of messages and
direct them to their intended target, even if the device is on a separate network and
uses a different network protocol.
Network Router
It also helps with segmenting the network to allow
access only for approved devices within that segment.
Network Router
Each computer on the network is assigned a ____ address.
unique
is a combination of a physical address from the computer’s hardware and a node address
given by the network.
The address
smaller exchange of information cuts down the load on the network and
allows more room for other requests
client-based network
One type of addressing is _________,
which is made up of four octets (groups of 8 bits) of numbers.
Internet protocol (IP) addressing
In the IP addressing, The numbers range
from __ to __
0 to 255
In the IP addressing, The first set of numbers indicates the _______, and the rest of the numbers tell other devices its _______.
network class,
exact location
The data travel along the network using an agreed-on set of rules known as a
network protocol
is a piece of the data with added information, such as the destination address, the source address, the sequence of the packets (e.g., 2 of 12), and whether there were any errors in transmission.
Packet
The protocol is delivered in layers of communication known as
protocol stacks
Typically a network communication model is explained using _____ layers (OSI
Model).
seven
Layer 4: The transport layer makes sure data packets are sequenced correctly
and that they do not contain errors. For example, the most common transportlayer protocol, the transmission control protocol (TCP), resides in layer 4
and manages the connection for the purpose of controlling the flow of the data
packets.
Layer 3: The network layer breaks up the data into frames and decides which
network path the frame will take to its destination. For example, the IP mentioned
above is concerned with sending the message to the correct address.
Layer 2: The data link layer packages the data so that they can be transmitted over
the physical layer. Ethernet is an example protocol that performs at layer 2 and
layer 1 levels.
Layer 1: The physical layer consists of the networking media and the components
required to pass on a signal from one end of the network to the other. This is the
layer that moves bits from one place to another.
We need to understand only the basic principles of network communication,
so we will simplify the model and concentrate on the bottom four layers.
is the physical (geometric) layout of the connected devices on a network.
Topology
is a network in which all devices are physically attached to and
listen for communication on a single wire
Bus
In a true bus network there is a single point
of failure, _______
the wire
is a full or standard computer which DOES not require processing from the server
Thick-client
is a lower processing power and heavily RELIES on the server
Thin-client
This type of topology does not need any switches or hubs
because the computers simply broadcast all the information down the single wire, and
all computers connected to that single wire receive the information
Bus
is a network in which the devices are connected in a circle
Ring
One type of ring topology is called a
token ring
The computers are connected in a
circle, and a token is transmitted around the ring
token ring
is a network that has the devices connected to a central hub or
switch
Star
can be thought of as a bus topology with the bus collapsed into
a central box: the hub or switch
Star
The data are sent through the hub out to the destination device
Star
This transmission of data may be through another hub or switch to an
adjacent network or directly to the device
Star
This is the most commonly used network
topology
Star
is a network that has multiple pathways interconnecting devices
and networks
Mesh
This type of network has redundancy built in with the multiple connections
Mesh
The Internet is based on this topology, and it is used most often to connect
networks to other networks
Mesh
DICOM
Digital Imaging and Communications in Medicine
has
become an almost universally accepted standard for exchanging medical images among
networked medical devices
DICOM
is layered on top of TCP/IP, the most common
network communication standard used, and it has multiple layers like TCP/IP
DICOM
DICOM was developed by the
American College of Radiology (ACR) and the
National Electrical Manufacturers Association (NEMA)
ACR
American College of Radiology
NEMA
National Electrical Manufacturers Association
The first version of DICOM was completed in ____, addressing only point-to-point connections between devices.
1985
DICOM (3.0) was better than its predecessors for several reasons:
-It required a communications protocol that runs on top of TCP/IP (or other standardized protocol stack), permitting the devices to make use of commercial hardware and software.
-It required strict contents of the image “header” and the structure of the pixel data itself for each type of modality, therefore improving INTEROPERABILITY.
-It required a conformance system, so that a user could determine from the vendor’s documentation whether the devices would operate together.
-It embraced an open standard of development between the vendors and users to
come to consensus on the direction of the standards
is maintained on a continuous basis and is published periodically
The standard (DICOM)
defines so-called service classes or functions that a device
can perform on a defined information object (like a CT image)
DICOM standard
is made up of 16 different parts ranging from image display to media storage
DICOM standard
known as RJ-45 jack
Twisted-pair wire
are commonly referred to as roles
SCU and SCP
SCU
Service Class User
SCP
Service Class Provider
The most common service classes
seen in modalities and PACS are:
- Image storage
- Query/retrieval
- Modality worklist
- Modality performed procedure
- Storage commitment
- Interchange media storage
The 16 parts of the DICOM Standard 3.1 (2004)
Part 1 Introduction and overview
Part 2 Conformance
Part 3 Information object definitions
Part 4 Service class specifications
Part 5 Data structures and encoding
Part 6 Data dictionary
Part 7 Message exchange
Part 8 Network communication support for message exchange
Part 9 Media storage and file format for media interchange
Part 10 Media storage application profiles
Part 11 Media formats and physical media for media interchange
Part 12 Grayscale standard display function
Part 13 Security and system management profiles
Part 14 Content mapping resource
Part 15 Explanatory information
Part 16 Web access to DICOM-persistent objects (WADO)
uses unique identifiers (UIDs) to globally identify each
image set, so that if the images are sent to multiple systems, the identifying number
will remain unique and not get confused with those images on other systems
DICOM
also provides a framework for the use of compression technologies on
image data
DICOM
is an American National Standards Institute (ANSI)–accredited Standards Developing Organization (SDO)
HL-7
It is used in most health care applications such as medical devices, imaging, insurance, and pharmacy
HL-7
oversees most clinical and administrative
data such as demographics, reports, claims, and orders
HL-7
As with DICOM, ____ is
composed of many parts and is used at many levels within various hospital systems
HL-7
It is the standard generally used in communication between the hospital information
system (HIS) and the radiology information system (RIS)
HL-7
holds the
patient’s full medical information, from hospital billing to the inpatient ordering system
hospital information
system (HIS)
holds all radiology-specific patient data, from the patient scheduling
information to the radiologist’s dictated and transcribed report
radiology information system (RIS)
is either a part of the HIS or runs along with it and contains all of the patient’s
record, including lab results, radiology reports, pathology results, and nurses’ and doctors’ notes
electronic medical record (EMR)
has recently come to the forefront of information technology.
electronic medical record (EMR)
interfaces with most of the ancillary service systems to retrieve
reports so that they can be viewed in this one common format.
EMR
Most modalities manufacture today are
DICOM conformant
When it receives data from a device, it generally sends those data to all devices connected to it. It does not know what the data are, nor to which device they
should go, so it simply forwards the bits.
Network Hub
computers, terminals, and servers that are interconnected by communication channels sharing data and program resources
computer network
MAN
Metropolitan Area Network
TAN
Tiny Area Network
CAN
Controller Area Network
Wireless connections that are costly and have the highest speed equipment
WAN
