HCIF Test Revision Flashcards
Explain the following terms:
a. Store and forward switching
b. Cut through switching
c. Symmetric switching
d. Asymmetric switching
a. Store and forward switching is a method of switching data packets by the switching device that receives the data frame and then checks for errors before forwarding the packets. It supports the efficient transmission of non-corrupted frames. It is generally used in telecommunication networks
b. Cut-through switching is a method for packet switching systems, wherein the switch starts forwarding a frame (or packet) before the whole frame has been received, normally as soon as the destination address and outgoing interface is determined. Compared to store and forward, this technique reduces latency through the switch and relies on the destination devices for error handling
c. Symmetric switching provides evenly distributed bandwidth to each port on the switch. A symmetric LAN switch provides switched connections between ports with the same bandwidth, such as all FastEthernet ports, for example. Symmetric switching is therefore optimized for a reasonably distributed traffic load, such as one found in a peer-to-peer environment
d. Asymmetric switching enables more bandwidth to be dedicated to a server switch port to prevent a bottleneck. This allows smoother traffic flows where multiple clients are communicating with a server at the same time. Memory buffering is required on an asymmetric switch
IP addressing – Class A, B, C networks and subnetting
Class A : 1 - 126 /8
Class B : 128 - 191 /16
Class C : 192 - 223 /24
Class D : 224 - 239 /Reserved for multicasting
Class E : 240 - 254 /Experimental
Define the terms: Hub, repeater
A hub is a network device that connects multiple devices together and allows them to communicate with each other. It is essentially a multi-port repeater, which means that it receives data from one device and then sends it to all other connected devices. Hubs cannot filter data, so all data packets are sent to all connected devices
A repeater is a network device that regenerates and amplifies signals to extend the length of a network. It operates at the physical layer and its job is to regenerate the signal over the same network before it becomes too weak or corrupted. An important point to note about repeaters is that they not only amplify the signal but also regenerate it. When the signal becomes weak, they copy it bit by bit and regenerate it at its original strength
Define Router and Switch
A router is a device that connects multiple networks together and directs traffic between them. It also allows networked devices to access the Internet.
A switch is a device that connects multiple devices within a network and facilitates the sharing of resources between them.
Write the protocols used for the following services in the data network (i) web and (ii)
email.
(i) HTTP
(ii) POP3, SMTP, IMAP
POP3 (Post Office Protocol version 3)
SMTP (Simple Mail Transfer Protocol)
IMAP (Internet Message Access Protocol)
Define the terms: HL7, DICOM, EMR
- Health Level 7
- Digital Imaging Communications in Medicine
- Electronic Medical Record
List the differences between LAN and WAN.
- LAN has small coverage while WAN has wide coverage
- LAN has higher data transfer rate than WAN
- WAN costs more than LAN
- LANs have lower latency and experience less data transmission faults than WANs
List the possible causes for the network connectivity problems in hospital networks.
Outdated network infrastructure
Bandwidth and capacity demands (A lot of devices, slow)
Security risks (data needs to be secure so measures may interfere with connection)
Procedure to identify the fault in the network that causes connectivity problems (7)
- Check Hardware
- Use ipconfig
- Use ping and tracert
- DNS check
- Contact ISP
- Check virus protection
- Review database logs
Routers:
a. Definition
b. Use of router in a data network
c. List the Interfaces and types of network connections
d. Information in the Startup config file
a. A router is a device that connects multiple networks together and directs traffic between them. It also allows networked devices to access the Internet.
b. Manage network traffic and allow multiple devices to use the same Internet
c. Can be used for physical (copper wire, wireless) and network layer connections
d. contains CISCO IOS software commands to customize functionality of device
What is DSSS (Direct Sequence Spead Spectrum)
This is a modulation technique designed to spread a signal over a larger frequency band. (Prevent interception in WW2)
What is FHSS (Frequency-Hopping Spread Spectrum)
This relies on spread spectrum methods to communicate. It transmits radio signals by rapidly switching a carrier signal among many frequency channels. Sender and receiver must know what channel to jump to. (walkie talkie)
What is OFDM (Orthogonal Frequency-Division Multiplexing)
This is a subset of frequency division multiplexing in which a single channel uses multiple sub-channels on adjacent frequencies.
