[comp.protocols.misc] osf-ncs vs. sun-rpc

mishkin@apollo.HP.COM (Nathaniel Mishkin) (07/06/90)

In article <404@bischeops.UUCP>, nick@bischeops.UUCP (Nick Bender) writes:
|> In article <1720010@hpbbi4.HP.COM>, markl@hpbbi4.HP.COM (#Mark Lufkin) writes:
|> ...
|> Stuff about NCS and Local Location Broker (LLB) and Global LB (GLB) deleted
|> ...
|> > 
|> > 	SUN RPC has something similar to the GLB called the portmapper. ...
|> 
|> Well, I haven't used NCS but I have used RPC (a lot). I think portmapper is
|> more analogous to LLB in that it is where services provided by a host are
|> registered. 

Exactly right.  The closest analogy is LLB<->Portmapper and GLB<->YP.  See
my other posting(s) in comp.protocols.misc for more details.

|> You can in fact get dynamic program numbers - that's the whole point of the
|> transient port numbers. HP even includes a little function called gettransient
|> which will return a newly bound transient port number. See the above manual
|> for the source.

I believe you're confused.  I don't see what transient port numbers have
to do with program numbers.  An application that wants to make a remote
call to a particular procedure in a particular interface needs to know
the ID (program number or UUID) of the interface a priori.  The ID is
embedded in the client's executable image.  In general, there is no way
to query anything for it.  The ID is the key, not the value, of lookups.
It is important that it be possible to easily get new unique IDs out
of the keyspace to ensure that two people don't accidently pick the same
one.  Sun RPC does not address this problem (unless you count calling up
Sun and asking for a program number as addressing the problem).

                    -- Nat Mishkin
                       Cooperative Object Computing Operation
                       Hewlett-Packard Company
                       mishkin@apollo.hp.com
                    -- Nat Mishkin
                       Cooperative Object Computing Operation
                       Hewlett-Packard Company
                       mishkin@apollo.hp.com