Again couple of questions

Cypunk

Now i'm getting in the hot-time, one week untill the test.

Hope somebody can answer these questions:

1. Is zubnet-zero valid in the exam?
2. Is the whole address range of ClassD Multicast? Or is it just 240?
3. Do i have to know supernetting?

Thanks

seth223uk

subnet zero is classed as not valid in the 607 exam this and the broadcast address ie 172.30.0.1 isnt invalid technically but in the context of the CCNA exam it is deemed not useable as is 172.30.255.x ie the broadcast is definately not assignable as it is reserved for the broadcast to the subnet. The same 2n-2 applies for the useable host derivation ie useable hosts is 2n-2 n being the number of subnet bits.

CCNA does not focus on anything outside class AB and C but just knowing that D is multicast should suffice and class D is all multicast im pretty sure.

classless routing such as CIDR and supernetting is more of a focus in the new CCNA exam than the 607 but still to be sure you should learn and understand the underlying principles.

hope this helps post back if it helps u if anyone spots any errors here post 2 im a bit tired lol

Cypunk

Many thanks. That answers my questions

seth223uk

so which exam is it your taking? I presume the new one?

Webmaster

Just wanted to add that in all Cisco exams (I believe the 607 also) CIDR or subnet-zero is mentioned in the question, so you can know exactly what to do.... subtract the 2 from the subnets or not.

There are two different RFCs covering subnetting. The first is know as 'traditional' subnetting, in which case you need to subtract the 2, since many people are used to 'traditional' subnetting (when actually calculating subnets). For a lively discussion about this...:

www.techexams.net/forums/viewtopic.php?t=447