"Segment" is a PDU (Protocol Data Unit) of Transport layer of OSI model. It is the data unit of transport layer. Network layer. DNS uses both TCP or UDP or both. UDP can handle only 512bytes. If data size is withing 512 bytes UDP is used, otherwise, TCP is used. IPSec is "Internet Protocol Security". It is a suite of protocols for securing Internet Protocol(IP) communications. Telnet = 23 and DNS = 53 ftp(data) = 20 and ftp=21 ARP stands for Address Resolution Protocol. It helps to find the hardware address or MAC address when IP address is known. Transport layer. To communicate several networks, routers are used. Routers have both broadcast domain and collision domain. RARP stands for Reverse Address Resolution Protocol. It helps to find the IP address when physical or hardware or MAC address is known. OSI model is a reference model containing 7 layers such as physical layer, data link layer, network layer, transport layer, session layer, presentation layer and application layer. TCP/IP model is an implementation of OSI reference model. It has five layers. They are: Network layer, Internet layer, Transport layer and Application layer. Important differences are: OSI is a reference model and TCP/IP is an implementation of OSI model. OSI has 7 layers whereas TCP/IP has only 4 layers The upper 3 layers of the OSI model is combined on the TCP/IP model. OSI has: physical layer, data link layer, network layer, transport layer, session layer, presentation layer and application layer TCP/IP has : Network layer, Internet layer, transport layer and application layer. All of them are devices and are used in network. Their differences are: Switch operates on which layer of OSI model? Normal switch operates at Layer 2 i.e. data link layer and Intelligent switch operates at Layer 3 i.e. network layer. DNS, FTP, Telnet, http ARP sents the request in broadcast, response is unicast Layer 4 MAC sublayer and LLC sublayer IP layer PDU is "packet". So, data is send as packet. 5 layers: Network layer, Internet layer, Transport layer and Application layer. In fact, Data Link layer has 2 sublayes: MAC sublayer & LLC sublayer.
What is the PDU of "Network layer" and "Data link layer".
DNS uses which protocol? Why?
Differentiate between forward lookup and reverse lookup in DNS?
What is IPSec?
What is the difference between flow control and error control?
What is the responsibilities of Network Layer?
Data link layer is sub-divide into how many groups?
What is the port number of Telnet and DNS?
What is the port number of ftp(data) and ftp?
ARP resolves what? MAC Address or IP?
Which layer of OSI is responsible for end-to-end communication?
Why we have to use router?
RARP resolves what? Address or IP?
What is OSI model?
What is TCP/IP model?
What is the full form of OSI and TCP/IP model?
What are the differences between OSI and TCP/IP model?
What are the differences among router, switch, bridge and hub?
How does ARP response the request?
Error control is down in which layer?
Name the 2 sublayers of data link layer.
How is data send by IP layer?
TCP/IP has how many layers?
What are the differences of MAC sublayer and LLC sublayer?
Can I determine remote machines MAC Address
The concept of MTU/fragmentation (not required, but nice if they know it)
The address resolution process at layer 3 (DNS)
The determination of local vs. non-local addresses (subnet masks/what are subnets/when to use a default gateway)
The address resolution process at layer 2 (ARP)
At least a vague understanding of layer 1 and associated issues
What is the difference between TCP and UDP? When would you use each of them?
What is a traceroute, and how does it work?
What is IPv6, and how does it differ from IPv4?
What is QoS? How does it work? Where would you apply it? When is it enforced?
What I'm looking for: knowledge of traffic prioritization schemes, at least a vague understanding of classification levels at the header level, understanding of judicious application to time and latency sensitive protocols, and knowledge of contention vs. non-contention
What is an MX record? An A record? A PTR?
Quick notes on TCP/IP that I seem forgetting all the time.
Common Terms -
What is "Segment"?
PDU for Network Layer aka IP is: "Packet" and PDU for Data Link Layer aka Ethernet is :"Frame"
PDU for TCP is segments and for UDP is datagram.
*** TCP is a stream protocol and so do not see data as packets. IP layer beneath it combines the fragmented packets.
You have one IP: 192.168.10.29. In which layer this IP works?
Which layer is closer to the user?
Layer 7 or Application layer is closer to the user.
What are the difference between TCP and UDP?
Name 4 example of application layer?
No, You need access to execute command on remote machine like psexec. You can try using trace route to see the last gw host.
Explain in detail the process of sending a piece of information from a host on subnet A to a host on subnet B.
Some knowledge of the OSI model
The concept of layers, layer units, and encapsulation.
What I'm looking for: someone who not only parrots the "connectionless vs. connection-oriented" idea, but can demonstrate they understand the reasons you might choose one or the other.
What I'm looking for: understanding of ICMP, TTL, and routing hops. Bonus points if they also know UDP trace routing.
What I'm looking for: basic understanding of the IPv6 address structure, differences such as ARP v. ND, and any associated knowledge of current IPv6 'state of the internet'.
What is NAT? Where would you use it? How does it work? What are some limitations?