9.3.1 Structure and function

• What is the Internet primarily based on in terms of communication protocols?

  TCP/IP
• The Internet is a global network of interconnected computers and servers that communicate using standardized protocols
• When you access a website, your device connects to a server to retrieve the webpage.
• Match the Internet tier with its description:

  Tier 1 ↔️ Large backbone networks

  Tier 2 ↔️ Regional networks

  Tier 3 ↔️ Local networks/ISPs
• Tier 1 networks form the core of the Internet.
• Tier 3 networks, such as ISPs, connect end-users to the Internet via Tier 2
• What is an example of a Tier 1 network?

  Level 3
• Tier 2 networks serve specific regions or countries.
• Which tier of the Internet includes local Internet Service Providers (ISPs)?

  Tier 3
• When you access a website, your local ISP connects to a regional network, which in turn connects to a Tier 1
• Internet Service Providers (ISPs) provide Internet access to individuals and businesses.
• What is the primary function of a router in a network?

  Direct data packets
• Routers use IP addresses to direct data between networks.
• Switches forward packets based on their MAC
• What do Internet Service Providers (ISPs) provide access to?

  The Internet
• Comcast and Verizon are examples of ISPs
• Routers and switches are essential devices in network communication.
• What do routers use to direct data packets between different networks?

  IP addresses
• Switches forward data packets within a local network based on MAC addresses.
• In a home network, a switch allows devices to communicate with each other locally.
• What is the primary function of DNS servers?

  Translate domain names to IP addresses
• The DNS process starts with the local DNS server checking its cache.
• Steps in the DNS resolution process:

  1️⃣ Local DNS server checks cache

  2️⃣ Root DNS server is consulted

  3️⃣ Top-level domain (TLD) server is queried

  4️⃣ Authoritative name server returns IP address
• Match the DNS term with its description:

  Domain name ↔️ Human-readable website address

  IP address ↔️ Numerical address of a server

  DNS server ↔️ Translates domain names into IP addresses
• What is the Internet primarily based on?

  TCP/IP protocols
• The Internet's hierarchical structure includes three tiers: Tier 1, Tier 2, and Tier 3.
• What type of networks are Tier 1 networks in the Internet's hierarchy?

  Core backbone networks
• ISPs manage network infrastructure to connect users to the Internet.
• ISPs offer services such as broadband, email, and web hosting.
• What do routers use to direct data packets between different networks?

  IP addresses
• Switches manage data flow within a local network based on MAC addresses.
• Match the network device with its function:

  Router ↔️ Connects different networks

  Switch ↔️ Manages intra-network traffic
• DNS servers translate domain names into IP addresses.
• Steps in the DNS lookup process:

  1️⃣ Local DNS server checks cache

  2️⃣ Root DNS server is consulted

  3️⃣ Top-level domain (TLD) server is queried

  4️⃣ Authoritative name server returns IP address
• What do domain names correspond to?

  Unique IP addresses
• What does the DNS system convert domain names into?

  IP addresses
• Order the steps involved in the DNS lookup process.

  1️⃣ Local DNS server queries

  2️⃣ Root DNS server directs to TLD server

  3️⃣ TLD server directs to authoritative name server

  4️⃣ Authoritative name server provides IP address
• The DNS server provided by your ISP is called a local DNS server.
• The root DNS server directs queries to the TLD servers.
• What type of domain does a Top-Level Domain (TLD) server manage?

  .com, .org, .net