After finishing this chapter you are responsible for being able to describe, define, and compare these concepts:

1. Engineering Problem Goal: Devise a set of protocols to handle large amounts of digital data

> Speed : How soon will it get there? How much bandwidth is required?
> Accuracy : Will it arrive error free? How much work must be done to fix errors?
> Power : How many watts are needed to get the job done over a given distance?
> Reliability : How robust is the network to damage?
> Security: How safe is the data from unwanted inspection or tampering?
> Implementation Cost : Hardware and coding issues translate into both time and energy.
> Operating Cost: Long-term costs that must be covered and exceeded by the income generated by the network.

4. General Knowledge Required:

a. All network designs should be optimized to take into account the trade-offs between the demands listed above.

b. Cost reduction has historically been a major driving force in the development of high speed data networks.

c. Relay nodes help reduce transmission costs. Routers, switches, and hubs are used together to optimize speed and the quality of service ("QOS") in a network of connected nodes.

d. Routers are crucial for store-and-forward systems such as the Postal Service or the Internet.

e. Switches are used for faster connections between relay points; voice circuits use this pathway to maintain a constant connection. Data packets can also be switched: this is a cheaper and faster option when a router isn't needed. Switches are more intelligent than hubs and allow for dedicated (instead of shared) segments for each node.

f.  Implementations of how the data is to be addressed, compressed, sent, transmitted, and received are called protocols. This prearrangement is required for the data networks to function properly. See specific protocols you must know in Item #4 below.
        > Know the 7 layers needed to obey the universal open system interconnection (OSI) model.

The 7 layers of the OSI Protocol Stack are, from the top where the user interacts, down to the hardware at the bottom:

Layer 7. Application: end user services such as email, ftp, telnet
Layer 6. Presentation: data problems, data compression and expansion
Layer 5. Session: authentication and authorization (e-commerce layer)
Layer 4. Transport: guarantee end-to-end delivery of packets (TCP)
Layer 3. Network: packet routing (IP & NAT)
Layer 2. Data Link: transmit and receive packets (MAC address)
Layer 1. Physical: The physical connection or cabling itself.

•  Be able to give an example of each layer in action. Layers 1-3 are the "transport set" while layers 4- 7 are the "application set"

7. TCP/IP controls are the current Internet protocols. Current specs use a 32 bit IP address (4 sets of 8 bits) and will be replaced by the new IPv6 (IP version 6) or IPng (IP next generation). In IPv6 addresses are 128 bits long and are represented in a different manner:
           > Values are in HEXADECIMAL format separated by a ':' (colon).
           > For example: FEDC:BA98:7654:3210:FEDD:BA22:3324:2122
           > This will allow for many more IP addresses, for just like with phone numbers in an area code, there is a finite
               supply of choices that are be consumed at an amazing rate. Universities and corporations are testing this
               protocol. More information can be found in the weblinks.
           > Be able to differentiate between IPv4 and IPv6 protocols and address construction 

8. Network Address Translation (NAT) protocol has been a necessity since networks, both for the home and business, have proliferated.
                   > Why was NAT invented?
                   > What does NAT do for St. Mark's computer network?
                   > What is a stub domain?
                   > What is a port (TCP or UDP)?

9. Packetizing data is a crucial aspect of digital networks. What sorts of information must be included in a data packet? See item #4 for identifying such information for different protocols.

10. Transmission protocols, and how data packets are sent over the Internet,  can be described as either "best effort delivery" (routed networks) and "guaranteed delivery" (switched networks).
            > You need to be able to use Traceroute utilities to trace a message packet from a given starting point to a given destination and explain the     
                routing table that is created. You may use web sites to visually trace your data packet

11. You are responsible for the vocabulary at the back of the Chapter. Being able to define, distinguish between, and give examples of each of these concepts will be crucial. In addition, be able to do the same for these concepts:
            > Layer 1 Network Topologies: packet switched vs. broadcast vs. Ethernet  or (ring) networks
            > The network hierarchy on the internet
            > Ports on firewalls/routers

5. Protocols to Boost Information Density in a channel:

  > Why  is it used in networks?  How does it work?

6. Math Required:

a. binary to hexadecimal (and back) conversions
b. geometry for network size layout
c. combinatorial math

    7. VAB Experiments

a. Design worksheet to utilize the IP packet transmit and/or receive VAB blocks for audio, images, and/or video

8. Exercises and problem solving for this Chapter:

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