Solved: ipv6,ipv4 mixed enviroment-scenario

sarahr202 · ‎09-05-2010

Hi every body

I have few questions

Scenario # 1

h1(ipv6/ipv4), h2(ipv4), h3(ipv6) , all are connected to hub.

Is it possible for h1 to have ipv4 and ipv6 addresses associated with the same NIC connected to hub?

will h1 use ipv4 address when it wants to talk to h2(ipv4) and use ipv6 address when it wants to talk to ipv6 host3?

Can we say h1 is dual stack host because it has both ipv4 and ipv6 configured on its port?

Scenario #2

h1( ipv4) and h2(ipv6) and router are connected to hub. Router is acting as a gateway. can router forward the ipv6 packets received from h2(ipv6) and ipv4 packets from h1(ipv4) on its port connected to hub?

Scenario #3

is it correct that we need dual stack some where to implement tunneling ?

For example:

H(ipv6)-------R--ipv4 network-----R-----H2(ipv6)

R stands for router. Here router will perform ipv6 to ipv4 tunneling so it should be dual stack correct?

H(ipv6/ipv4)---------( ipv4 network)------H(ipv6/ipv4)

Dual stack has to be implemented on Hosts to implement tunneling correct?

thanks and have a great weekend.

Giuseppe Larosa · ‎09-05-2010

Hello Sarah,

scenario1:

your understanding is correct and h1 is a dual stack host.

>> Is it possible for h1 to have ipv4 and ipv6 addresses associated with the same NIC connected to hub?

yes, the hub or L2 switch is agnostic of upper layers

>> will h1 use ipv4 address when it wants to talk to h2(ipv4) and use ipv6 address when it wants to talk to ipv6 host3?

yes

scenario2:

>> h1( ipv4) and h2(ipv6) and router are connected to hub. Router is acting as a gateway. can router forward the ipv6 packets received from h2(ipv6) and ipv4 packets from h1(ipv4) on its port connected to hub?

yes, there is no difference for hub L2 switch between an host NIC and a router NIC

notice that IPv6 has a different ethertype (0x86DD) then IPv4 (0x0800) so there is no risk of confusion for hosts.

scenario3:

yes your understanding is correct in first case R1 and R2 have to be dual stack, in second case are the hosts to be dual stack to send IPv6 packets into IPv4 packets over an IPv4 cloud.

Hope to help

Giuseppe

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Giuseppe Larosa · ‎09-05-2010