Summarizing - reverse engineer?

Crasam

Hi

Wondering if someone would be able to help. I'm currently studying for the ccna exam and Ive covered the majority of topics. If given a number of addresses I can summarize them fine.
Ive been doing some practice exams from various places and was wondering if there is a quicker way rather than writing out all the binary for each address, when presented with a question like below as it seems to take a while.
I know in this case its only needs to be done in the third octet as its a /21.

The networks connected to router R2 have been summarized as a 192.168.176.0/21 route and sent to R1. Which two packet
destination addresses will R1 forward to R2? (choose two)

192.168.194.160
192.168.183.41
192.168.159.2
192.168.183.255
192.168.179.4
192.168.184.45


Thanks for your help

vinbuck

The only thing that will really help you as far as speed is subnetting practice. There are various methods out there for subnetting in your head and most if not all of them are listed on this board. I just took the CCNA and it took me about 20 seconds to dissect the problem you listed because i've put a ton of work into subnetting. If you put the time in on subnet problems, you will start to see the patterns in subnetting that will help you achieve speed on the exam.

rogue2shadow

MississippiGuardsman wrote: »

The only thing that will really help you as far as speed is subnetting practice. There are various methods out there for subnetting in your head and most if not all of them are listed on this board. I just took the CCNA and it took me about 20 seconds to dissect the problem you listed because i've put a ton of work into subnetting. If you put the time in on subnet problems, you will start to see the patterns in subnetting that will help you achieve speed on the exam.

+1. The Cisco binary game will also serve you well