Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: [802.21] HLSI



On Wed, Sep 07, 2005 at 05:33:09AM -0700, Gupta, Vivek G wrote:
> 
> -----Original Message-----
> From: stds-802-21@LISTSERV.IEEE.ORG
> [mailto:stds-802-21@LISTSERV.IEEE.ORG] On Behalf Of Yoshihiro Ohba
> Sent: Tuesday, September 06, 2005 9:42 AM
> To: Subir Das
> Cc: STDS-802-21@LISTSERV.IEEE.ORG
> Subject: Re: [802.21] HLSI
> 
> The currently defined Cipher Suites and Authentication Method are too
> 802.11 specific, and not useful information for other media.  I think
> what we actually need in basic set is more generic security and qos
> suites like Jesse Walker prensented a couple of meetings before (is
> there updated information about Jesse's work?).  We can have
> placeholder Security and QoS IEs at this moment, and continue the work
> of defining their contents for a few months.
> 
> Besides that we should also discuss whether media-specific security
> parameters should be defined in basic set or extended set.  I think
> they should be defined in extended set in order to avoid definition of
> tons of media-specific TLVs in the 802.21 specification.
> 
> [Vivek G Gupta] 
> 
> The network technology independent IEs are quite few. Based on current
> discussions we are left with:
> { Operator (that provides access to IS),  List of Networks Supported }

I think Cost, List Of Roaming Partners, IP_Version, HLSI capabilities
are media-independent.  Data_Rates and Neighbor_Maps can be
media-independent if they are specified in a generic way.

> 
> The values of most of other IEs are network technology dependent:
> { Operator,
>   Cipher_Suites, 
>   Authentication_Methods, 
>   Cost (free/not free), 
>   List Of Roaming Partners (Agreements),
>   IP_Version, 
>   Data_Rates (range), 
>   QoS Supported, 
>   Neighbor_Maps,
>   HLSI capabilities 
> }
> 
> In a very generic scenario the steps in querying information can be as
> follows:

> Step 1: Query the list of networks in an area
> Step 2: Query set of properties (listed above) for each network.

I have some doubt about the usefulness of Step 2.  Does Step 2 assume
that all PoAs of a given type of network have the same set of
properties?  I don't think so.  If there are multiple neighboring
802.11 networks each operated by a different roaming partner, we
should not assume these networks have the same set of properties.


> Step 3: Query specific neighbor reports and any other extended detailed
> information

I think Step 3 is more important than other steps to make an efficient
handover decision.  I believe this is where schema-based query is
really needed based on a consistent format across different types of
networks and using a standard, flexible query language.

> 
> From a basic set perspective we just identify the key IEs that need to
> be supported by different network technologies. Their values are likely
> to be technology specific and hence it probably is not such a good idea
> to club them together etc. Clients could query these IEs for specific
> networks using common query mechanism and expect results in consistent
> format across different networks. The individual network standards could
> be amended so tat the 802.21 Info server (however it is deployed) could
> easily obtain the above parameters from different access networks.
> Other IEs that need to be supported could be vendor/operator/ or network
> technology specific and we could just make a provision for their
> transport.
> 
> So not sure if we really need to get into basic/extended schema set type
> discussions and also of trying to collate values of different IEs across
> different network technologies.

Please see my comment above on why schema is needed.  Also, without a
schema and a schema-based query language, it is not possible to make
the following types of queries in an efficient way:

- "Give me a list of 802.11g supported neighboring access points
operated by an operator that has a roaming agreement with operator X."

- "Tell me a list of 802.11 access points or 802.16 base stations
within one-mile of the point of attachment to which I am currently
associated."

- "Tell me the IP address and prefix of the access router on the same
IP link as a given point of attachment."

Regards,
Yoshihiro Ohba

> 
> Best Regards
> -Vivek