9 Network Practice and Troubleshooting Free Online FlashCards

What does the OSI Transport layer provide?

The Transport layer provides process-to-process delivery and uses ports; it supports reliable delivery with TCP or datagrams with UDP.

How do TCP/IP layers roughly map to OSI layers?

TCP/IP application functions commonly span OSI layers 5–7. TCP/IP transport roughly corresponds to layer 4, Internet to layer 3, and link to layers 1–2.

How is a browser request encapsulated for transmission?

A browser request is application data; TCP may carry it in a segment, IP in a packet, and Ethernet or Wi-Fi in a local-link frame. The receiver processes the layers in reverse.

Which port and transports does DNS commonly use?

DNS commonly uses port 53 over both TCP and UDP.

How do TCP and UDP differ in delivery?

TCP provides a reliable, ordered byte stream. UDP sends datagrams without TCP’s delivery guarantees.

What is the difference between an IP address and a MAC address?

An IP address identifies a network-layer interface for traffic across networks; a MAC address supports delivery on a local link.

Which IPv4 ranges are reserved for private networks?

The private IPv4 ranges are 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16. They are not globally routed as public Internet addresses.

What are the network, broadcast, and usable host addresses for 192.168.10.77/26?

For 192.168.10.77/26, the network address is 192.168.10.64 and the broadcast address is 192.168.10.127. Usable host addresses range from 192.168.10.65 to 192.168.10.126.

How do a switch and a router differ?

A switch commonly forwards local-network Ethernet frames using MAC addresses. A router connects IP networks and forwards packets using IP routes.

A website works by IP address but not by domain name. What should you check?

Investigate DNS name resolution: test the configured DNS server and the name lookup. Reaching the server by IP does not establish that name resolution works.

Does ping use a TCP or UDP port?

Ping uses ICMP, which does not use TCP or UDP ports.

What is a default gateway?

A default gateway is the router a host uses to reach destinations outside its local subnet.