IPv6 prefix interpretation

[a.mberdavey121]

I have a very basic question about IPv6 prefix. Taking a very simple example about prefix notation:

"2001:db8:abcd:0012::0/64"

My question is: Do we call the whole thing under quote as prefix or just the value after back slash?

In general term, I understand that prefix is a way to tell how many bits of the IPv6 address is actually the network part. In above example, it is clearly that first 64 bits (8 octets) are Network address and remaining 64 bits(8 octets) will be Host Identifier. But, to be precise, when we talk about prefix, do we end up calling that number after back slash(i.e 64 in above example) as prefix or the whole thing (entire thing under double quotes)as prefix ? I would like to get 100% clear about the terminology and its interpretation? Please share your kind response.

[balaji.bandi]

2001:db8:abcd:0012::0   - This is IPV6 address

/64  - Prefex Length

[Harold Ritter]

Hi @a.mberdavey121 ,

When we say prefix we refer strictly to the network portion of the address and the host portion (referred to interface identifier in the ipv6 world) is set to zero. Here's a few example:

::/0 (default route)

2001:db8::/32

2001:db8:1000::/36

2001:db8:1200::/40

2001:db8:12f0::/44

2001:db8:12ff::/48

2001:db8:12ff:1000::/52

2001:db8:12ff:1100/56

2001:db8:12ff:1110/60

2001:db8:12ff:1111/64

etc ...

For more information refer to to the following document:

https://en.wikipedia.org/wiki/IPv6_address

Regards,