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I'm starting studying IPv6 and I'm having some troubles understanding some aspects.

Let's clarify if I'm getting this right! A single host may have: - a unicast global address - a link local address Then it joins multicast groups, solicited node group for example, one for each unicast address.

My first question is: If a host needs to send a packet, which is its source address? the link-local one or the global one?

Now, let's move to ARP. I've read ARP no longer exists. If I need to send a packet towards a host which is on my same link I'll use neighbor-solicitation to obtain its local-link address. First of all...is this the real goal of this procedure? To obtain the local-link address?

Then...I suppose the IPv6 packet will be encapsulated within an Ethernet frame...which is its destination address considering braodcast is no longer an option and we don't know the MAC of the other host?

I've read, the IPv6 packet is sent to the multicast group "solicited-node", whose last 24 bits are obtained from the address of the target...but how can I create it if the address of the target is what i want to obtain?

Hope you can help go through this fog :) thanks in advance!

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The protocols commonly used to assign global addresses depend on the host already having a link-local address. So in most cases link-local is mandatory rather than optional.

A host can have multiple local and multiple global addresses assigned to each interface.

Source IP must be in the proper scope for the destination address a packet is send to. So sending to a link-local address will use link-local source. And sending to a global address will use a global source. If a packet is send to a global address through an interface which doesn't have a global address the host might use a global address from a different interface.

ARP isn't used for IPv6. But when running IPv6 on Ethernet a replacement is needed. That is ND which is more or less just ARP encapsulated in ICMPv6 packets.

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