[comp.protocols.iso] ESIS multicast

mckellar@pinocchio.encore.com (Steve McKellar) (07/06/90)

Help!

I'm working on a tp4 implementation, and the ESIS multicast addresses defaults
are: 

es address (destination for ISH's) = 09002B000004
		&
is address (destination for ESH's) = 09002B000005

The problem: our uk customer insists that uk gosip specifies the reverse
(es address = 09002B000005, is address = 09002B000004), although our osi 
supplier claims uk gosip conformance using the defaults. 

Can anyone out there shed any light on this for me?


Thanks in advance,

Steve McKellar

dougm@WARTHOG.NCSL.NIST.GOV (Doug Montgomery) (07/06/90)

 
The NIST OIW agreements cite for 802.3 and 802.4:
	ALL_ESs = 0900 2B00 0004
	ALL_ISs = 0900 2B00 0005

and for 802.5:
	ALL_ESs = C000 0000 4000
	ALL_ISs = C000 0000 8000


Note: maybe you and your UK customer are justing getting
your meanings crossed.  ISs "use" the ALL_ESs address
when sending ISHs and ESs "use" the ALL_ISs address. 

dougm

sch@sequent.UUCP (Steve Hemminger) (07/06/90)

Unfortunately, some early OSI documents had typo's for these addresses
and some equipment has them backwards.

The values assigned by the NIST Stable Implementation Agreements are:

On 802.3 networks:
	all ES:	09 00 2B 00 00 04
	all IS:	09 00 2B 00 00 05

On 802.5 networks:
	all ES: C000 0000 4000
	all IS: C000 0000 8000

tozz@hpindda.HP.COM (Bob Tausworthe) (07/08/90)

> / hpindda:comp.protocols.iso / mckellar@pinocchio.encore.com (Steve McKellar) / 12:11 pm  Jul  5, 1990 /
> Help!
> 
> I'm working on a tp4 implementation, and the ESIS multicast addresses defaults
> are: 
> 
> es address (destination for ISH's) = 09002B000004
> 		&
> is address (destination for ESH's) = 09002B000005
> 
> The problem: our uk customer insists that uk gosip specifies the reverse
> (es address = 09002B000005, is address = 09002B000004), although our osi 
> supplier claims uk gosip conformance using the defaults. 
> 
> Can anyone out there shed any light on this for me?
> 
> 
> Thanks in advance,
> 
> Steve McKellar
> ----------

According to the UK GOSIP Spec. Version 3.1, published Jan 31, 1990,
section 4.7.5.5 ES-IS Protocol:

   two multicast addresses are required for use in conjunction with the
   ES-IS protocol and shall be LOCALLY CONFIGURABLE. A default value for
   these addresses is:

   All_ISN = 09 00 2b 00 00 04
   All_ESN = 09 00 2b 00 00 05


So yes, your worst nightmares have come true. 

The problem arises because the first edition of NIST implementor's 
agreements specified the incorrect values (those above, thanks guys),
and everybody went along (MAP 3.0, UK GOSIP, EN/ENV 41 102 . . .),
then later in the latest version of NIST, they were 
changed to the right values. All profiles except UK GOSIP have
ammended themselves to use the new values.

IS THERE SOMEBODY OUT THERE CONNECTED WITH UK GOSIP WHO CAN EXPLAIN TO US
WHY THE 1/90 VERSION OF UK GOSIP WAS NOT UPDATED TO REFLECT THE NEW VALUES??

Even though the multicast addresses are supposed to be locally configurable
in most profiles (MAP 3.0, UK GOSIP. . .), many vendors have hardwired them,
and this is going to lead to some nasty interoperability problems in
the future.

So my answer to you is:
  1) your uk customer is correct from their profile point of view
  2) make sure your implementation allows the multicast addresses
     to be configurable so you are conformant, and interoperable.

		      Bob Tausworthe
		      Hewlett Packard
------------------------------------------------------------------------------
These opinions are my own, unfortunately, not my employers.

crhodes@se-sd.SanDiego.NCR.COM (Chris Rhodes) (07/12/90)

Under what circumstances are multicast addresses used?

Is it for Network Entity traffic only, or can multicast addresses
be used as SNPA addresses? 

The advantage of using multicast addresses as SNPA addresses being 
that configuration changes would not be required whenever a 
network card is replaced in an ES or IS. A possible problem 
however, if multiple ISs exist on the one LAN, which IS does the 
routing?

If this is simply an implementation issue, does anyone have
any thoughts of pros and cons of whether or not to use multicast
addresses this way?

Regards,
-- 
*  Chris Rhodes, Communication Network Systems, NCR, SE-San Diego *
*  Email Chris.Rhodes@SanDiego.NCR.COM                            *
*  Phone (619) 693 5511   Fax (619) 693 5494                      *

tozz@hpindda.HP.COM (Bob Tausworthe) (07/14/90)

> / hpindda:comp.protocols.iso / crhodes@se-sd.SanDiego.NCR.COM (Chris Rhodes) /  4:26 pm  Jul 11, 1990 /
> 
> Under what circumstances are multicast addresses used?
> 
> Is it for Network Entity traffic only, or can multicast addresses
> be used as SNPA addresses? 
> 
> The advantage of using multicast addresses as SNPA addresses being 
> that configuration changes would not be required whenever a 
> network card is replaced in an ES or IS. A possible problem 
> however, if multiple ISs exist on the one LAN, which IS does the 
> routing?
> 
> If this is simply an implementation issue, does anyone have
> any thoughts of pros and cons of whether or not to use multicast
> addresses this way?
> 
> Regards,
> -- 
> *  Chris Rhodes, Communication Network Systems, NCR, SE-San Diego *
> *  Email Chris.Rhodes@SanDiego.NCR.COM                            *
> *  Phone (619) 693 5511   Fax (619) 693 5494                      *
> ----------

Multicast addresses are used by the ES-IS protocol for the following
functionality: Report Configuration, Query Configuration.

The multicast addresses are SNPA addresses, not Internet Addresses.

If multiple IS exist on a LAN, the ES-IS protocol states that ANY of
them do the routing. If an ES sends to an IS, and that IS decides that
another IS on the LAN is better suited to route the packet, the IS will
forward the packet to that IS and then send a Route Redirect message
to the sending ES telling it where to send subsequent packets FOR that
route.

		      Bob Tausworthe
		      Hewlett Packard
-------------------------------------------------------------------------------
These opinions are my own, unfortunately, not my employer's