IP Network Services

Question 1

TCP vs UDP?

Answer 1

TCP: Sequenced, Reliable, Connection-oriented, ACKs, Windowing flow control, high overhead

UDP: Unsequenced, Unreliable, Connectionless, no ACKs, no Windowing flow control, low overhead

Question 2

What are some Application Layer Protocols?

Answer 2

1. Telnet/SSH
2. FTP
3. TFTP
4. SNMP
5. HTTP/HTTPS
6. NTP
7. DNS
8. DHCP/BootP

Question 3

What is a socket?

Answer 3

Processes are assigned unique port numbers.

Question 4

Types of Port Numbers and what they are for?

Answer 4

20/21: FTP(TCP)
22: SSH(TCP)
23: Telnet(TCP)
25: SMTP(TCP)
53: DNS(UDP/TCP)
67/68:DHCP(UDP/TCP)
69:TFT(UDP)
80: HTTP(TCP)
443: HTTPS(TCP)
123: NTP(UDP/TCP)
161/162: SNMP(UDP)

Question 5

What is telnet for?

Answer 5

Remote login
Cleartext
No Security

Question 6

What is SSH for?

Answer 6

Remote login

Secure

Question 7

What is FTP for?

Answer 7

Cleartext communication

Not secure

Question 8

What is TFTP for?

Answer 8

Simple file download
Cisco devices transfer configuration file or ios image
Security not a concern

Question 9

What is SNMP for?

Answer 9

Collects and manipulate valuable network info

Question 10

What is HTTP for?

Answer 10

Communication between web server and web client for file and other information exchange

Question 11

What is NTP for?

Answer 11

Provides time to devices connected to internet

Question 12

What is DNS for?

Answer 12

Resolves hostnames (specifically internet names)

Question 13

What is the DHCP Client Four-step Process?

Answer 13

1. Discovery
2. Offer
3. Request
4. Acknowledgment