RE: Q on Ver.-05 of draft-ietf-radext-ipv6-access after IETF81 radext session

Hello Leaf,

The different attributes proposed in this draft for the pools name have all the same format (a string), but semantically they are different, as they coved different scenarios.

As you also summarized in your email below,

Framed-Pool was designed for the IPv4 address pool;

Framed-IPv6-Pool was designed for the IPv6 SLAAC prefix pool;

Delegated-IPv6-Prefix-Pool is designed for DHCPv6-PD prefix pool;

Stateful-IPv6-Address-Pool is designed for DHCPv6 address pool;

So each attribute covers a different use-case/scenario and they can appear in the same RADIUS packet at the same time.

If you want to use a single pool name use to cover all the 4 use cases listed above, you would also need to define a standard format/syntax for the pool name that allows the NAS to be able to disambiguate among the different scenarios and in order to do that the NAS would need to have an extra logic to infer the semantic of that specific attribute from the assigned name.

Instead if you have a specific attribute for each specific scenario, the semantic is mapped to the attribute name, thus the NAS does not need an extra logic to discovery the purpose of that pool and the pool name can be any string, no limitation or special syntax is forced for the pool name.

Thanks,

Regards,

Roberta

From: owner-radiusext@ops.ietf.org [mailto:owner-radiusext@ops.ietf.org] On Behalf Of Leaf yeh
Sent: lunedì 25 luglio 2011 18.23
To: draft-ietf-radext-ipv6-access@tools.ietf.org; radiusext@ops.ietf.org
Cc: fine_sz@huawei.com; Qiujin; Wangshuxiang
Subject: Q on Ver.-05 of draft-ietf-radext-ipv6-access after IETF81 radext session

Question for clarification:

We already have the following Radius Attributes for the address/prefix pools:

Framed-Pool (88, section 5.18 of RFC2869),

Framed-IPv6-Pool (100, section 2.6 of RFC3162).

http://www.iana.org/assignments/radius-types/radius-types.xml

The foramt are the same as follows:

0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | String...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

draft-ietf-radext-ipv6-access-05 is proposing 2 new attributes for address/prefix pools:

Delegated-IPv6-Prefix-Pool,
Stateful-IPv6-Address-Pool,

the fomat of these 2 attributes are the same as the above one.

Supposed the above attributes could be explained as follows:

Framed-Pool was designed for the IPv4 address pool;

Framed-IPv6-Pool was designed for the IPv6 SLAAC prefix pool;

Delegated-IPv6-Prefix-Pool is designed for DHCPv6-PD prefix pool;

Stateful-IPv6-Address-Pool is designed for DHCPv6 address pool;

All above attributes are only used to provide the name of the address/prefix pools in a 'string'. I doubt the necessity to make so many 'name' or 'string' attributes for the different address/prefix pools to prevent the ambiguity. I guess 1 attribute for the name of the address/prefix pools might be enough. In fact, the NAS take the role to interpret the meaning of the pook name, right?

I think Framed-Pool can be re-used for the design purpose of Stateful-IPv6-Address-Pool. Do we have any limitation on the usage of Framed-Pool for IPv6?

I think Framed-IPv6-Pool can be re-used for the design purpose of Delegated-IPv6-Prefix-Pool to indicate a pool of IPv6 prefix pool. I could even think Framed-Pool can replace Framed-IPv6-Pool to indicate the name of a IPv6 prefix/address pool per the same logic. Am I right?

Best Regards,

Leaf