I came across a quizz as below:
Which of the following IPv4 addresses could potentially be assigned to a laptop’s NIC card? (Select two answers)
169.254.200.1
126.99.99.255
127.45.22.1
169.200.1.1
The answers are: 2 and 4, I guess they makes sense because 2 and 4 are belonged to class-A and class-B respectively, while 3 is the loopback address.
May I ask why the answer 1 (169.254.200.1) is not the case? I believe 1 is actually also belonged to the class-B address range, from 128.x.x.x.x to 191.x.x.x.x.
Any address starting with 169.254.x.x is technically called an APIPA address (Automatic Private IP Address). The local TCP/IP stack within a device will give itself this address if DHCP fails (no DHCP Offer is received) and it technically is only meant to allow sending/receiving of packets on the local link (should not be routed).
That’s why 169.254.200.1 is an incorrect answer. Because one would never intentionally configure this address (manually) on a NIC card…and a DHCP server will never offer this address via the DHCP process.
Regardless the IP class, there are a few IP blocks that are reserved for special purposes. APIPA, Loopback etc are examples for that. If the system is not able to fetch an IP from the DHCP server, then the NIC gets assigned with an APIPA IP ( range 169.254.0.0/16).
Thanks Keith, I must have missed something in your lecture, I’m pretty sure that I took note of all important points haha :’)…, but I got it now, I’ll be more careful with the reserved IP addresses, really appreciate your time.
Hi Jaa, I really forgot the reserved IP addresses …, :’), thanks a lot for reminding me! Hope to see your support with my noob’s questions in the future, thanks for your time.
