Subject: RE: [mobile-ip] MIPv6 v20 site-local addresses

From: "Greg O'Shea" <[email-masked]>
Date: Wed, 12 Feb 2003 20:37:43 -0000

Yes, that looks reasonable. I guess more thought on site local is
required. Multi-homed with multiple sites using same site-prefix is the
challenge.

>-----Original Message-----
>From: Ed Remmell [mailto:[email-masked]] 
>Sent: 12 February 2003 19:19
>To: Greg O'Shea; [email-masked]
>Subject: RE: [mobile-ip] MIPv6 v20 site-local addresses
>
>
>I have identified the following MN use case for site-local scope:
>
>"Access Internal System behind Corporate Firewall
>In some cases, the user wants to communicate with an internal 
>system behind the corporate firewall. The internal system in 
>this case has a site-local scope address. The user has 
>configured (either auto- or manually) a site-local scope 
>address with a matching prefix on their virtual home 
>interface. When they send to the site-local address of the 
>internal system, we will find a prefix match on the virtual 
>home interface, and because the address is site-local scope we 
>will always use the MN-to-HA tunnel to send to that 
>destination. Alternatively, if we don't find a prefix match 
>but if they specify a source address which is configured on 
>the virtual home interface, that will cause us to select the 
>virtual home interface as the outgoing interface, and then in 
>the virtual device send function on that interface we will see 
>that the destination address is site-local scope and so we 
>must send it using the HA tunnel in this case."
>
>So, I think that being able to participate in site-local scope 
>communication with nodes on its home network while the mobile 
>node is on a foreign link is a potentially useful feature that 
>should not be removed.
>
>BTW, "virtual home interface" is what we use to 
>store/configure the MN's home addresses on when it is attached 
>to a foreign link. This is associated a virtual device driver, 
>which uses the MN-to-HA tunnel to tunnel packets sent to 
>site-local destination addresses that originate on that 
>interface. We use the source IP address of the packet in our 
>routing decision to select the correct outgoing interface, 
>when mobile node functionality is enabled. Probably more than 
>you wanted to know ;-)
>
>Thanks.
>- Ed Remmell
>Elmic Systems, USA
>http://www.elmic.com
>
>-----Original Message-----
>From: [email-masked]
>[mailto:[email-masked]]On Behalf Of Greg O'Shea
>Sent: Wednesday, February 12, 2003 11:05 AM
>To: [email-masked]
>Subject: [mobile-ip] MIPv6 v20 site-local addresses
>
>
>Packets addressed to the mobile node's site-local address 
>SHOULD NOT be tunneled to the mobile node by default, but this 
>behavior MUST be configurable to enable it; [10.4.2] Why is it 
>a good idea for site-local to be configurable? Text elsewhere 
>states that we don't know how to deal with site-local in MIPv6 
>[4.6, 10.4.2] and I agree with that so for a change I won't 
>bother to point out examples of entanglement. How can we 
>specify configurable use of site-local when we can't specify 
>what could or should happen when it's enabled? Especially when 
>you're multi-homed. For now I think site-local should be out. 
>It can be reviewed e.g. at DS time or better still as a 
>separate doc when we understand what it means.
>
>

---

From: "Hesham Soliman (EAB)" <[email-masked]>
Date: Wed, 12 Feb 2003 21:49:37 +0100

Greg, 

>Packets addressed to the mobile node's site-local address SHOULD NOT be tunneled to the >>>>mobile node by default, but this behavior MUST be configurable to enable it; [10.4.2]
>Why is it a good idea for site-local to be configurable? Text elsewhere states that we >>>>don't know how to deal with site-local in MIPv6 [4.6, 10.4.2] and I agree with that so for a >change I won't bother to point out examples of entanglement. How can we specify >>configurable use of site-local when we can't specify what could or should happen when it's >>enabled? Especially when you're multi-homed. For now I think site-local should be out. It >can be reviewed e.g. at DS time or better still as a separate doc when we understand what >>it means. 

=> What is the operational problem with the text above? We had a long 
discussion on SLs and this was the conclusion, is something going to break
because of this text?

Hesham

PS: Any chance you can turn off html?

---

From: "Greg O'Shea" <[email-masked]>
Date: Thu, 13 Feb 2003 18:44:16 -0000

Okay with me.

>From: Jari Arkko [mailto:[email-masked]] 
>Sent: 13 February 2003 17:50
>To: Ed Remmell
>Cc: Greg O'Shea; [email-masked]
>Subject: Re: [mobile-ip] MIPv6 v20 site-local addresses
>
>
>Ed Remmell wrote:
>
>>>Personally I hate to see something as loose as the current text in a 
>>>spec, but I guess you had better leave things as they are until the 
>>>adventurous have more to report.
>> 
>> 
>> This is my opinion too, although the current looseness w/ regards to 
>> site-local doesn't bother me as much.
>
>Yeah. So why don't we stick to SHOULD NOTs in the places that
>I suggested... that leaves the spec pretty clear and still 
>allows folks to go do their site local stuff if they really 
>need and they understand what they are doing?
>
>Jari
>
>