First, I would like to know what is the ideal broadcast domain size. I guess it is always to better to have more collision domains. But I have not been taught about the ideal broadcast domain size. So, I googled and figured out that the ideal braodcast domain size is usually is /22. In other words, 1024 - 2(Network ID + Broadcasting Address) hosts can be in one network. If /22 is the correct answer for my question, could you please explain to me why /22 is the ideal broadcast domain size?
For address resolution protocol, I see 0.0.0.0 or 255.255.255.255 as a target address in Wireshark. In packet tracer, the target address is always 0.0.0.0. Which one is right target address? I would appreciate if you can give me some explanations between 0.0.0.0 and 255.255.255.255 as the target address.
What happens if ARP cashe overflows? I asked people around me, but sadly none of them knows what actually happens if ARP cashe overflows. I am curious about the ARP cache overflow because static routing by outgoing interface in point to multipoint case could be really dangerous and ARP cache overflows could happen.
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I am literally new to the IT. I recently started to study network and programming(Python) from no computer or network background. So, probably my answers are not right, but I will give a shot.
I guess, if PCs and VoIP phones are sharing a same port(PCs or VoIP phones would get packets they don't want which leads to burning resources). In this case, I guess the best solution is to separate them using VLANs. If PCs and VoIP phones have their own port, I guess you don't need to separate them by VLANs, but you don't want the boradcast domain size too big because of broadcasting traffics.
For ARP one, I think ARP cache overflow could happen in router only if I configure my router by static routing + outgoing interface. So best solution I can think of at this point, using static routing + next hop address.
I am literally a newbie. Please let me know if my solutions are not correct.
I am a super newbie. But, I will take another shot. First, if they are not sharing the port, the vendor would definitely recommand bigger max network sizes. Because, if they are sharing the port, they are also sharing the bandwidth. Thus, if they are not sharing the port -> not sharing the port's bandwidth -> PCs and Phones can be more chatty -> More Boradcast Traffics can be allowed -> Broadcast Domain Size can be increased -> the vendor would definitely recommand bigger max network sizes.
For second question, I honestly am not sure what to do since I have never seen a ARP cache overflow! If I can manually change the ARP cache size, I would definitely increase it. But since I have never heard about the increasing ARP cache size, I guess this solution probably won't work. The best solution I can think of at this point is to check which interface is point to multipoint. Then, I would check the routing table. If the point to multipoint interface is configured using the outgoing interface, I would fix it to the next hop. If that still doesn't fix the problem, I would call the CISCO :)