WAN/PACS/DICOM

1. What are the wide area networks and what types of WAN are you familiar with?

Wide area networks are networks that provide long distance links to organizations. These networks belong to third party carriers and are generally used to link local area networks (LANs).  WANs connect multiple forms of traffic including data and imaging etc. through fixed lines or cloud services (Cowley, 2012).

Frame Relay is a type of WAN that uses a frame cloud to communicate data via frame cloud service. Frame relay unlike other WANs is a more affordable model that offers variable bandwidth to clients. Digital subscriber line (DSL) is a more popular WAN that uses multiple frequencies to relay data. Unlike similar leased line models this network is slower and has reduced data rates the further away it is from the central telephone exchange (Cowley, 2012).

2. Pick three types of WAN: describe, provide basic structure and/or configuration, explain potential use in healthcare settings.

 Frame relay is a virtual technology offered by a telephone company that allows you to transfer data through a centralized frame cloud. Frame relay is leased on a committed information rate (CIR) that allows you to purchase a specific bandwidth that you assume you would need to transfer data between facilitates. This model is unique in itself because it allows for your data to “burst” above CIR. This means that at any given time depending on the availability you are able to send data at much faster rates than negotiated at no additional cost. This type of WAN is on a shared network with others and is not distance sensitive which helps reduce costs that you see with similar WANs, such as , leased lines (Cutright & Girrard, 1996).

Frame relay uses a frame relay access device that encapsulates data at the source. This data is then transferred over a permanent virtual circuit (PVC) or switched virtual circuit (SVC) in order to transfer data via the frame relay cloud to its designated location (Cowley, 2012) Ideally this type of WAN will be more  beneficial to healthcare organization that have facilities in different states. The available bit rate (ABR) allowed by the frame relay model to allow for faster data speeds then negotiated is beneficial to organizations. Moreover, not having a cost for distance will save organizations money, especially those that operate across the country.

Asynchronous  transfer mode (ATM) is similar to frame relays virtual network. However, this network transfers data by use of switch and cell technology to transfer data. This type of network is used to transfer different sources of traffic. Particularly video conferencing and voice being sent via an ATM would see most benefits. Healthcare organizations that plan to implement telemedicine to provide access to rural communities with satellite offices may benefit from this type of WAN. The ATM allows for little latency thus increasing telemedicine capabilities, image sharing, and voice connection capabilities. ATM has standard bandwidths and do not offer the same flexibility as frame relay (Cowley, 2012).

Leased lines are also third party owned and have a standard bandwidth. These networks use a point to point link typically an integrated services digital network (ISDN) connection that uses traditional copper wired technology to connect facilities. This model is more expensive than both ATM and frame relay with charges for distance and set bandwidth. Organizations are limited to the bandwidth purchased and have set rates that do not fluctuate with usage. This model is more reliable then both ATM and frame relay, and can transfer vast amounts of data at any given time. The benefits of leased lines are that these networks are privately leased which offer more protection that public networks. This type of WAN can benefits organizations that need reliable connection and who can afford to pay for additional bandwidth that goes unused (Cowley, 2012).

3. What is cloud computing? What is its basic structure? What are its advantages and disadvantages? What is its potential use in healthcare, as well as challenges and strategic advantages?

Cloud computing is a service that offers information sharing over the internet and generally offered in three architectures including software as a service (SAAS), information as a service (IAAS), and platform as a service (PAAS). Cloud technology uses a pay for use model and the different architectures allow customers to leverage the models depending on need. Infrastructure as a service for example provides the hardware and infrastructure needed at a rental fee and has fast access to services (Cowley, 2012).

 Some of the benefits the cloud offers are reliable data transferring and flexible applications. This type of network has a pay for use model which is beneficial to organizations that have down time on data usage and are not required to pay a set rate such as leased line models. However, clouds also have disadvantages in that they rely on internet connectivity to transfer and share data across the network. If there is downtime this could potentially disrupt an organization communications (Cowley, 2012). Although cloud computing seems to be a phenomenal concept that has the potential to improve connectivity. There are many concerns about security. Primarily these concerns arise from third party owned data centers. The issue is since the data is not stored in-house; organizations have little say on how and where the data is stored (Hamlen, Kantarcioglu, Khan, & Thuraisingham, 2012).

Healthcare organizations can benefit from cloud computing due to flexibility and pay for use models. On a SAAS model organizations lease applications from third parties eliminating the need for central data centers and hardware acquisitions. With the vast amount of data being stored in healthcare organization can benefit from flexible payment models that charge by usage rather than charging a set fee. This decreases overhead costs of unused data (Cowley, 2012).

4. What is domain name system, what is its purpose, how does it work?

A domain name system (DNS) gives IP addresses a textual name that is easy for humans to memorize. Unlike IP addresses that are created in numerical format to allow computers to recognize other computers or websites. Domain names translate the IP numerical address into a textual format that is stored over a domain name server, which memorizes domain names attached to an IP address (Cowley, 2012).

The benefits and purpose of having a domain name system is to make it easier for humans to communicate with computers. Computers communicate in numerical format, and humans do not understand this language. Therefore, having a domain name attached to an IP makes it more efficient and easier for humans to communicate instructions to computers. DNS simplifies search engines and makes every day online activities possible such as shopping and searching the web (DNS Made Easy, 2012).

DNS is a multi-level querying system that stores associated domain names to IP addresses. The querying system works in separate tiers depending on where data is stored. The different tiers for example are DNS cache, DNS query, and root name servers. Once the search is complete the data is passed back to the main computer in a format that humans understand (Gonyea, 2010)

5. Describe the concepts of DICOM and PACS. What is the fundamental difference between these two terminologies?

Picture archiving and communication system (PACS) is an archiving system used to store images including MRI and CT, 2D and 3D images. This technology is used to make the retrieval of images easier for organizations to share, compare, and review images instantly. The images are shared over a common network making images easily accessible in digital format (Rouse, 2015).

Digital Imaging and communications in medicine (DICOM) is a protocol established to set the standard for storing, retrieving, and the sharing of images. According to Bidgood et al (1997) DICOM addresses five application areas that are important for managing the storage and sharing of images. The fundamental difference between DICOM and PACS is what they are used for. PACS is the actual system itself where as DICOM is an established set of rules on how medical images should be handled. 

References

Bidgood, W. D., Horii, S. C., Prior, F. W., & Van Syckle, D. E. (1997). Understanding and Using DICOM, the Data Interchange Standard for Biomedical Imaging. Journal of the American Medical Informatics Association, 4(3), 199–212. Retrieved from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC61235/

Cowley, J. (2012) Communications and Networking. Westmidlands, UK: Springer

Cutright, P. J., & Girrard, K. M. (1996). Frame relay. What does it mean?. Online, 20(3), 68. Retrieved from: http://search.ebscohost.com.proxy.cc.uic.edu/login.aspx?direct=true&db=f5h&AN=9605151252&site=ehost-live

DNS Made Easy. (February 27, 2012). DNS explained. Retrieved from: https://www.youtube.com/watch?v=72snZctFFtA

Gonyea, C. (2010). Dns: why its important & how it works. Retrieved from: http://dyn.com/blog/dns-why-its-important-how-it-works/

Hamlen, K., Kantarcioglu, M., Khan, L., & Thuraisingham, B. (2012). Security issues for cloud computing. Optimizing Information Security and Advancing Privacy Assurance: New Technologies: New Technologies, 150. doi: 10.4018/jisp.2010040103

Rouse, M. (2015). Pacs (picture archiving and communication system). Retrieved from: http://searchhealthit.techtarget.com/definition/picture-archiving-and-communication-system-PACS