Networking Basics and Performance

Networking Terminology

• The primary goal is to understand networking terms.
• The Internet constitutes a network of networks.
• A protocol in networking refers to a standardized set of rules governing communication.
• HTTP exemplifies a network application.
• Packet switches are responsible for forwarding packets.
• Fiber optic communication utilizes glass fibers as its transmission medium.
• Routers forward packets between different networks.
• Bandwidth denotes the measure of data transmission speed.
• Circuit switching is characterized by reserving resources, unlike packet switching.
• The IETF is responsible for creating Internet standards.

Network Performance Metrics

• Queuing delay measures the waiting time of a packet at a router.
• DSL has a maximum transmission rate of 24 Mbps.
• A bottleneck signifies a point of congestion.
• Throughput indicates the rate of successful message delivery.
• Nodal processing typically causes a delay of less than 1 millisecond.
• DSL typically supports an upstream transmission rate of 2.5 Mbps.
• Transmission delay is typically L/R seconds.
• Propagation delay is typically d/s seconds.

Protocols and Layers

• TCP is responsible for providing reliable data transfer.
• The physical layer transfers bits over a physical medium.
• DNS translates domain names into IP addresses.
• RFCs are documents detailing Internet standards.
• The transport layer is responsible for reliable data transmission.
• The application layer supports network applications.

Network Types and Technologies

• Cable modems commonly offer a transmission rate of 30 Mbps.
• Ethernet provides transmission rates that includes 10 Mbps, 100 Mbps, and 1 Gbps.
• A "mesh" network is characterized by interconnected devices.
• Fiber optic cables offer the advantage of high-speed transmission.
• HFC networks combine fiber and coaxial cables.
• Wireless networks are characterized by their flexibility and mobility.

Network Security

• A DoS attack is an attempt to make resources unavailable.
• IP spoofing involves sending packets with a false source address.
• Firewalls filter network traffic.
• The main goal of network security is to protect against attacks.

Switching Methods

• Packet switching enables resource sharing.
• In packet switching, "store-and-forward" means the entire packet must arrive before forwarding.
• Excessive congestion is a primary disadvantage of packet switching.
• Circuit-switched networks reserve resources for a call.

Network Components and Functions

• Network switches connect multiple devices within a network.
• Content provider networks bring content closer to end users.
• The Internet backbone provides high-speed connections between ISPs.
• Network protocols define message formats and actions.
• A NIC provides a physical connection to a network.
• A modem modulates and demodulates signals.

Network Analysis and Management

• Traceroute programs measure delay from source to destination.
• Network monitoring tools analyze network performance.

Physical Characteristics

• Typical propagation speed of a signal in a physical medium is 2 x 10^8 m/sec.

Access Networks

• Shared access networks involve users sharing the same bandwidth.