WWDC2004 Session 504

Transcript

Kind: captions
Language: en
ladies and gentlemen enough
introduce our first presenter and that
would be architect dr. Stuart chess Eyre
okay I want to thank you all for coming
it's great to see such a full room on a
Friday morning last day of the
conference and I'd like to believe that
it's because you're here to see me but I
know it's really because you've all
experienced firsthand the frustration of
trying to set up network devices and
apples not the first company to realize
the importance of this but I believe
we're the first companies to succeed
with a solution that really works I'd
like to start with a show of hands how
many people in the room now are our IT
administrators network administrators ok
that's a good turnout so we have a lot
of new stuff in rendezvous this year
this has been the biggest year for
rendezvous and we've got more stuff to
announce this year than last year or the
year before so I'm going to get right
into it we've got so much new stuff we
should be calling it rendezvous two or
super rendezvous or something so there
are three big areas where we've gone
beyond Panther in three different
dimensions we've gone beyond the local
lamp in Jaguar and Panther rendezvous
was focused at the area of IP networking
that's least well served which is a
small network just plugging things
together but in tiger we now expand that
beyond the local lan using standard
unicast queries and updates people have
raised this criticism before I rendevouz
only for local networks it doesn't scale
to the enterprise well we've left the
enterprise behind because we're built on
dns dns is a worldwide database it's the
biggest distributed database in the
world and because of that in Tiger you
can browse any domain that's advertising
services anywhere on the planet from
anywhere on the planet so
what we now scale for the whole planet
we go beyond the old rendezvous in
another very important way which is
while we always had the Darwin code
which ran on a variety of different
platforms it was a little bit
inaccessible what we have today just
announced this week is a rendezvous
system service demon running in the
background just like it does on OS 10
running on linux freebsd solaris other
unix systems and of course windows how
many people in the audience developed
for windows nearly half exactly exactly
as we expected and the good news now you
can go to the apple developer website
and download our technology preview for
windows run the installer and you get
the exact same dns underscore sdh API
that's provided on Panther the same API
that's provided on linux and freebsd
insularis in the unix platforms so the
same c code you write is now portable
across all of those platforms and the
other way we go beyond the old
rendezvous is beyond CA p is the current
AP is our see header files we now have a
fully supported java class library that
provides you the full functionality
when ancestor as a talk at javaone this
week and got a big enthusiastic reaction
there as well Java people have been
waiting for this a long time so you have
the full suite of rendezvous facilities
available to you but with
object-oriented Java style api's and the
other area where we go beyond rendezvous
is not just Java but we go beyond C to C
sharp visual basics and all of the
dotnet languages on windows as well so
you can now write visual basic programs
using rendezvous so an outline of what
we're going to talk about today I'm
going to recap what rendezvous is about
because most Mac users and developers
know about it but I want to make sure
that we're not leaving anybody behind
we're going to talk about the wide area
reserved discovery in advertising we're
going to show you rendezvous running on
Windows and on the unix platforms we're
going to tell you about the java api and
the api that we have in panther proved
to be very good we didn't have any bugs
or missions to fix but we have added a
couple of new helper functions which
I'll tell you about and you may have
seen a setting up here we just had a
whole suitcase full of stuff we had the
rendezvous plugfest at the apple campus
last night and we told people that they
brought cool stuff then we try to show
it and we've got a whole suitcase of
stuff so if it weren't for rendezvous it
would be insane to try to set up 20
different devices in 15 minutes to do a
demo but because the rendezvous will
we'll see if this works and we we hope
to have time for Q&A at the end so quick
recap what is rendezvous first and most
important is it's a philosophy it's an
attitude it's the attitude that you
should be able to just plug things in
and have them work without fussing with
addresses and subnet masks and nonsense
configuration and that's what's most
important and I always say that first
because people forget that rendezvous is
not about technology rendezvous is about
the goal of making products that just
work if you think about plugging
USB device you don't have to type
addresses to configure it you just plug
it in and there's no reason ethernet
should be any different or wireless so
that's the most important thing but
there are underlying technologies that
will enable us to reach that version and
those are addressing naming and
discovery now I'm not going to go into
these in the same detail I have a
previous talks but just to recap you're
not going to do much IP addressing
without an address dhcp is great but if
there isn't dhcp server on the network
all of these rendezvous devices will
pick their own address second thing
having a bunch of random IP addresses is
certainly a first step but it's not
sufficient because if you don't ought
all the IP addresses are you're not a
lot better off so the second step is
naming a normal usage model for internet
software is DNS hostnames DNS is great
if you have a DNS server but if you
don't then we need a safety net and the
safety net is multicast DNS where you
send a standard format DNS query you
multicast it to everybody on the local
network and each device has its little
multicast DNS responder and when it sees
a query for its name it says that's me
and it answers so this doesn't replace
your compete with global scale wide area
DNS but it's the safety net when you
have just two devices on a cable or
three or four devices in the hub and you
don't have a DNS server setup and the
third leg is discovering because using
host names is better than using
addresses but you still need to know
what name to use and discovery lets you
browse the network like be faithful old
appletalk user and see what's out there
and click on it without having to know
in advance what the name is and why do
you care as product developers well you
care because if the user can't use your
product then they're going to call you
they're going to run up support costs
and ultimately they may return it I
witnessed something as a start-up a few
years ago in here in California in
Silicon Valley at the heart of the
computer and three they bought a $1,500
high-end HP LaserJet printer double
sided stapling in
corners very very beautiful fancy
machine plug it into the network
appletalk auto configured the mac users
were printing on it right away they
could not get IP setup like these were
guys with masters and PhDs from Stanford
during the dot-com startup they could
not make it work after two days they put
it back in the styrofoam took you back
to frys and returned it and that's just
a tragic story which is why today every
major printer vendor has rendezvous in
their printers because they don't want
they don't want the printers being
returned but what is more exciting to me
it's not just taking the current stuff
and making it easier but the fact that
when you don't have to configure it
entirely new product categories have
become possible and and that's where I
think we're going to see a lot of the
exciting things you will all have seen
the announcement for our Airport Express
this has no screen this has no keyboard
but it shows up in a pop-up menu in
itunes for you to play your music that
wouldn't be possible if you had to type
in addresses and netmask and things that
this products wouldn't exist so that's
where i think we're going to see the
excitement in the next couple of years
so to summarize rendezvous has grown
both in bretts and in depth it's grown
in breath in terms of reaching more
platforms and more languages and it's
grown also in the it now skills beyond
the local link geographically it's grown
to scale to the whole world
so don't even try to read this I'm not
here to talk to you today about upnp but
when we have whenever we meet with
developers it's a question that comes up
what about you pnp and the upnp forum
loves to proclaim how many hundreds of
companies they have signed up for their
forum but they only have one credible
product today after all those years of
work and i'm being generous by even
calling it credible that's it that's the
upnp home gateway protocol and it really
doesn't even work very well but that's
the only thing that they can kind of
point to is that their success well
nevermind the forum and the hundreds of
companies we have hundreds of products
this is from the list of registered
rendezvous service types from the dns
service discovery website and this is
just the first page and it goes on and i
won't go page after page after page
we're on to the letter I here we're only
on the 9th letters of alphabet every one
of these registered services this is not
a product this is a protocol for every
one of these there are one or more
service advertising that there are one
or more clients browsing for that if
it's a network game it may be serving a
client from the same company in the case
of protocols like ssh telnet FTP there
are of course dozens of servicing
clients advertising that so we have this
huge adoption this quite revolution
going on that people almost aren't aware
of and the daily this list of registered
rendezvous services gets longer and
longer so on that note I'd like to
invite Curren a car up on stage to tell
you all about wide area around
Thank You Stuart so glad to see all of
you out here I know the morning after a
beer bash can be tough but I'm very
excited to be here and tell you about
what we're doing here my name is Kiran
sacar and I've been involved with the
rendezvous team at Apple for almost two
years now and for Tiger I'm focusing
specifically on our wide area
initiatives now Stuart mentioned when we
started off with local rendezvous a few
years back we aimed squarely on the
local network because that was the area
that was least served by IP networking
and the most amazing thing happened once
everyone tried it the first thing they
asked invariably was how can we get this
beyond the local network suddenly the
area that had the worst user experience
became the model for how we're going to
move forward now we have this viable
solution on all these platforms for the
local network and we are ready to move
forward and we have a very clear vision
as to how we're going to do so the first
and the most sweeping of these goals is
to bring the zero configuration ease of
use everywhere from the local networks
where we started to enterprises and
education all the way to the internet
and in doing so we're going to bring
reach ability to everybody reach ability
isn't something that you should have to
have a static IP address for and have
the savvy to set it up and even if you
do have these things well once you go
mobile your reach ability goes out the
door imagine you move between your home
your office and an internet cafe short
of actually getting on the phone and
calling up your friends and telling them
your IP address reaching you is like
finding a needle in the haystack now in
pursuing this vision we're going to have
a very broad reaching impact on all of
you take for instance this doesn't use
rendezvous
take for instance a network game all of
a sudden you can collaborate with
another game player across the internet
with just a couple API calls it's that
easy it provides a great user experience
and it's easy for you to allowing you to
focus on your core competencies which is
creating great applications not messing
around with this networking stuff if you
manage a network environment like in an
enterprise you might have found yourself
choosing between a network that's easy
for you to administer and a network
that's easy for your your users to
interact with and with wide area
rendezvous you get both and of course
life local rendezvous has done wide area
rendezvous will add a competitive
advantage to your hardware products
making them better for your customers to
interact with and ultimately lowering
your support toss now as Stuart
explained when we set about solving the
local problem we focused on a few core
pieces of functionality and moving
forward with wide area rendezvous we're
doing the exact same thing first we give
every machine a dynamic dns hostname
this is much like the link local name on
local rendezvous but now the name is
globally unique meaning it can be looked
up an access from anywhere and this name
is persistent meaning as you move
between your home and your cafe and your
office the name stays the same even as
your IP address changes this is the
first big step towards reach ability
this alone brings us so much
functionality but we go ahead and take
it a step further first of all we don't
want to have to remember these names and
even more importantly we want to learn
about new machines that we didn't know
about before but they're providing some
service that's of interest to us so we
take the DNS service discovery and
registration that we have on the local
network and publish this into a global
name space where these services can be
accessed potentially from anywhere now
it's
easiest to explain the architecture to
the solutions of this functionality in
the framework of local rendezvous that
we all know local rendezvous of course
starts with dynamic dns our pardon to
the dns service discovery on the top and
that is the AP is that your application
is used to browse and register for
services and of course the resource
record format using standard DNS
messages to encode information about
your services now beneath this we have
multicast DNS the server lyst protocol
for registering and querying for these
DNS records on the local network with
wide area rendezvous we simply slide out
the multicast DNS layer and use unicast
Vienna communicating directly with a DNS
server now in the difference between
this architecture and our previous local
architecture what has stayed the same is
just as important if not more important
than what has changed and that's DNS
service discovery this means that our AP
is our one hundred percent unchanged the
exact API is that you've been using for
the last two years we'll give you all of
this new wide area functionality with
little to no modification in your
applications when we first did local
rendezvous many people ask why are we
using the DNS message format and back
then we did have some good reasons there
were a wealth of debugging tools
developers are already knew the message
format just to name a few but now is
where we see the really big win by
making that decision for local
rendezvous we're allowed to keep the
same protocol in the same API s and
instead communicate with the state with
these DNS servers that automatically
know how to understand our messages we
can look at some of the specific
advantages of DNS both on the discovery
using the DNS queries and the
registration side using dynamic updates
let's start looking with by looking at
registration
pardon me with discovery to discover a
service or to look up information about
a service we format a standard DNS query
like we would have done with local
rendezvous and instead of sending it out
on the network we send it directly to
our DNS server and get an answer it's
really that easy but along with it being
easy we inherit this huge wealth of
advantages that DNS has to offer DNS has
extensive caching DNS is distributed in
nature and perhaps most importantly DNS
is ubiquitous there are servers
everywhere now getting the information
off the server is pretty easy but how do
we get information to the server how do
we publish our services and register our
name after all dns was initially a
relatively made for a relatively static
data set when it did change it was
usually an administrator actually typing
in something in a text file
unfortunately that problem has been
solved for us as well with dynamic dns
update as you probably know dynamic
update allows the client to publish
resource records into a server and we
use this to publish our global globally
unique address record and this is one of
the more conventional uses for dynamic
update in addition we take our service
records the records like the pointer
record the txt record the SRV record
that convey information about the
services that we're offering and publish
those into the DNS as well now we have
this distributed system of databases
just ready to accept our services which
ones are we going to use well if you
manage an enterprise network chances are
you might set one up and we've gone
ahead and set one up too and it turns
out it's pretty big that's right dot Mac
now supports dynamic dns this is
included with a standard mac service and
each user gets their own name user
members maxcom within this domain they
can publish the names of
any number of machines that they own and
any number of services that they wish to
advertise the server was built from the
ground up to support wide area
rendezvous so the software is highly
tuned and unless you come from Virginia
Tech the rack of extras will make you
drool but it turns out if you're not
supporting half a million users you
don't need anything like that in fact a
standard DNS server will work just fine
and that's what we do with our tiger
server offering we use by nine the tried
and tested DNS server and include a UI
that makes setting up wide area
rendezvous even easier now when we're
registering into these servers and
potentially across the internet with Mac
this of course creates a whole new range
of possibilities for the visibility of
our services with dot Mac services are
truly globally visible when you publish
your name and your services anyone on
the internet can discover them but you
don't have to set your network up this
way if you are managing an enterprise
network you probably don't even want
that you probably want your services
registered securely behind a firewall
and DNS offers us that kind of
flexibility using techniques like what
namespaces you can do much as you do
with your website having your publicly
visible website as well as an internal
website that's only visible behind the
firewall this brings us to another
advantage of using the domain name
system not only there are there so many
technical advantages but we also get
this wealth of administrative expertise
there are already thousands of people
many of them are in this room who know
how to set up a DNS server and guess
what now you're also a wide area
rendezvous administrative expert now if
you're an administrator deciding how
you're going to set up your wide area
rendezvous network or you're an
application developer planning to
publish your services into the dot Mac
system it's worth thinking a bit about
what kind of visibility you
on and what's this visibility means for
you well let's take the extreme example
the dot Mac example when you publish
your services anyone can find them from
anywhere but that's where it stops at
discovery once someone discovers the
service they'll have to connect to your
service and it's up to you to have the
kind of access control and security
that's appropriate for your application
so what's the message secure your app
but as it turns out this discovery
mechanism doesn't actually introduce any
new vulnerabilities if a hacker wants to
if you're providing a service they could
find you even without this kind of
discovery what this does is it makes
just makes it easier for those with
legitimate reasons to find your services
and be able to interact with them now
one area that's particularly challenging
in terms of visibility is networks that
are behind nat gateways as you might
know and that allows a single public IP
address to be shared amongst a number of
private addresses for example an airport
base station plugged into a DSL line
often acts as an that now then that
detects outbound connections say one of
the machines talking to a web server and
it'll change the addresses in the
packets to make them look right and
it'll remember this outbound request so
when a reply comes it'll know which
miscue machine behind the gateway to
send it to unfortunately there's no way
for the nat to know when a machine
behind it is actually providing a
service and there's no way for machines
outside of the gateway to connect to
these machines with their private
addresses now the reality of networking
today is that machines are more and more
finding themselves behind these mat
gateways and it's simply not acceptable
to force them into this cloud of
isolation if they're in this kind of a
network configuration that's why we've
created a natural versatile protocol
it's a very simple protocol that allows
the machine behind that gateway to learn
public IP address and to request the
public port that it can then maintain
with a lease life and a refresh much
like dhb p and this effectively allows
machines behind the net gateway to be
able to accept connections incoming
connections from outside of that gateway
I'm glad to hear that you're all
enthusiastic about this and of course
following in the rendezvous tradition
this is an open specification which is
now available in a preliminary form on
our websites and if you're interested in
using this in your products by all means
come talk to us now this promotion this
protocol is a highly complementary to
wide area rendezvous but it turns out
that the rendezvous stack is also the
ideal place to implement it in white
area rendezvous we use the protocol to
find what our public IP address is so
that when we register our names in the
DNS we're registering a public address
that can be reached from anywhere when
an application registers the service
using our service registration api's
we'll go ahead and take care of the NAT
mapping for them will maintain the
leases and the refreshes and all this is
completely hidden from the client you
don't even have to worry about it now if
for some reason you don't want this if
you don't want a port map for you just
register your service in the local
domain only and we won't do any kind of
wide area registration for you we won't
create any nap mappings for you but your
service will continue to work on the
local network now this protocol gives us
huge flexibility in terms of the range
of visibility and all of a sudden we can
have a person registering a service on
one side of the globe and someone
discovering it on the other and as the
physical distance increases we clearly
need some kind of authentication
mechanism for publishing our services
take for instance the dot Mac service if
we had this without any kind of
authentication someone could register
something say a photo share in my domain
other people will discover it think it's
mine and when they resolve it they will
actually get directed to this Impostors
machine and who knows we might end up
finding pictures that I just don't want
my grandmother to see fortunately DNS
standards provide us with an easy
solution for this we use the transaction
signature resource record also known as
a tea cig and what this is is a
cryptographic hash of the dynamic
updates which includes all of the
messages pardon me all the records and
the services that will be publishing as
well as a shared secret known by my
machine and the server and this
effectively allows the server to
determine that I do in fact have the
authorization to publish records in a
given domain now all of this is
available with why area rendezvous and
in the dot Mac case it just works
seamlessly but it's not required as part
of the protocol if you're setting on up
the network that's behind a firewall
with a relatively small number of users
you might decide that you don't even
need authentication you got by with
Apple talk for years without it and you
trust your employees you don't have to
have it you have that kind of
flexibility now looking at all these
different pieces the authentication than
that traversal the dynamic updates the
queries we get a more detailed
architecture of the white area
rendezvous system and what this really
is is a novel combination of existing
technologies in a way that provides a
very valuable and powerful experience
but if you look at this long enough and
believe me we did eventually you'll find
some holes let's look under the
discovery sign
with local rendezvous we have this
notion of a long-lived query when we
start a browse say in ichat you get all
the answers that are available on the
network and your list immediately
populates but this browse this query
maintains for the length of time you
have that window open so as new services
become available or old services go away
your list maintained it your list is
updated and it's live it's snappy and it
provides that great experience that we
all like unfortunately there's no
equivalent with unicast DNS we have a
couple options here we could deal with
failed data you could maybe add a
refresh button to your application and
if you've ever heard Stewart talk before
you know you're more likely to see a big
flat your powerbook or we could pull the
server very rapidly and find out about
changes that way now that would make us
fall back into the chattiness that
plagued appletalk and it would
completely preclude this kind of
scalability that we need for a half a
million users in dot mac so it looks
like the DNS standards got us pretty
close but they stopped a little bit
short of giving us a solution that we
need as it turns out dns actually comes
through by offering its own extension
mechanism this is called edn s0 and it's
a standard way of enhancing the DNS
protocol to provide new functionality as
it becomes necessary we use this
extension mechanism to create long-lived
queries this is a special kind of query
where we ask the server to give us all
of the answers that it knows and then to
continue to tell us as new answers
become available or answers that it
previously gave us becoming valid this
provides the same kind of browsing
experience that we have on the local
network while still being high
performance and highly scalable
similarly on the registration side we've
got a piece missing under dynamic update
with dynamic update we published a
resource record into the database and it
stays there until we d register it which
works fine some of the time but imagine
i plug my laptop in within to the
ethernet jack and i register a bunch of
services and then i unplug the cable
well guess what those services stay up
there on the dns even though my machine
is no longer reachable and they'll stay
there indefinitely for this prob we end
up with the same stale data problem and
we address this too with the ed and s0
extension mechanism we add a least life
to resource records so that we tell the
server to publish them and hold them for
a certain amount of time which we can
periodically refresh if we need to and
then if the Machine becomes disconnected
from the network where the power goes
out or what have you before too long the
server will realize that the machine
isn't there anymore the lease is expired
and it will actually go ahead and remove
those records from its database now
these extensions are done with DNS
native extension mechanism but they
clearly require some kind of
modification to the server and there are
a couple ways we can make this happen in
the dot Mac servers because they were
designed specifically for wide-area
rendezvous these extensions are
supported natively it can do long live
queries and it can handle Leafs life's
just like it can standard queries and
standard dynamic updates but we design
these extensions so that they can also
be implemented as a side process running
next to a stock unmodified name server
this is what we do with our tiger
offering we use by nine which is tried
and tested and it works great and next
to it we will have a process that
understands long-lived queries
understand the Leafs lives and
essentially acts as a broker between the
clients and the servers and
specifications pulmonary preliminary
specifications for these extensions are
posted on the website and you're welcome
to take a look at them and implement
them in your servers if you so choose
now looking at implementation it's worth
taking a look at what kind of
application implementation and what kind
of application changes need to be made
to take advantage of this in our
discovery ap is you might have wondered
why we have this domain parameter after
all it's always just been local well now
you see why in fact we have encouraged
you as developers to not explicitly
specify a domain when you make your
registration calls and when you make
your browser calls just pass the empty
string and let us pick you something for
you and up until now that's always just
been local but now that we have this new
capability we can make intelligent
choices for you about where to browse
and where to publish services for
example a default browser registration
call might take place both on the local
network and in a user's Mac domain now
of course if you have explicit needs by
all means pass an explicit domain if
your service really only makes sense in
the context of the local network than
just past local likewise if you want to
be looking in a specific dot Mac members
domain perhaps for some kind of a
collaborative application or a game then
just pass that members domain if you
want to we have calls that will provide
a list of available domains that you can
browse and register in and you can
actually let your client pick one in a
graphical user interface these
enumeration calls have been around all
the time and up until now they've only
returned local but now they'll return
local as well as one or more dot Mac
domains and possibly even other domains
that we learn about from our network
environment well enough of hearing me
talk let's take a look at how some real
applications use this stuff can we go to
the demo please
early demo three thank you here we have
a tiger machine thank you here we have a
tiger machine and as you can see I'm in
the dot maxpreps pain and there's this
new tab called domain this allows us to
turn on the dot mac dns service I've
checked it on here and you can see the
name of my computer portable Kieran
members matcom Kieran members mac com is
my personal domain where I can register
in and portable is the name of this
machine that I've sat in our sharing
press Spain now this is a standard DNS
name you can use it in the connect to
dialogue you can use them the terminal
anything that takes a dns name but we
can also use rendezvous for browsing of
course we don't have to use this name
explicitly we can take a look in safari
in the rendezvous tab and sure enough
i'm actually not seeing anything I'm not
seeing any rendezvous shares here let's
see if we can't figure out why that's
happening I have a machine at home and I
want to be able to see its website and I
thought it was publishing in the dot mac
and i know i have apple remote desktop
turned on there so let's see if i can't
actually get into it and see what's
happening now here too i could enter
that the name of my home machine but i
don't have to here we have an unmodified
application apple remote desktop that
does rendezvous browsing and doesn't
specify an explicit domain so the system
goes ahead and publishes both locally
and in my dot math domain and here we
can see my desktop machine with its IP
address here which is not on our local
network and i can go ahead and add it
and here we see the difference between
discovery and actual access anyone can
discover that i have apple remote
desktop but you still need to correct
zation to access a machine and now I can
connect to it here too we can see that I
have dot Mac turned on Mac domains
turned on and that's why I was able to
see it from here in the conference room
and you can see its name desktop in my
same in my same personal domain now
let's take a look at why web sharing
wasn't working well that would explain
it it's not turned on so we can look
back in our safari browser here and
Safari has a long-lived query
established with the server which means
that it's asked for all the answers and
in fact there weren't any but the server
will continue to tell it as new answers
come about so if i go ahead and turn on
web sharing here it'll fire up apache
register my services both on my local
network at home and in my dot mac domain
go ahead and turn it on takes a few
seconds for Safari to launch and there
it is
it's amazing to think about how many
things happens have to happen there the
registration has to send the records to
the dns server the dns has to notice
this change and send the notification to
my machine here and it's still just as
snappy as it is on the local network you
can see it disappear and reappear it
actually takes longer for Safari to lots
for Apache to fire up than it does for
the registration to take place and we
can go ahead and double click on it and
resolve the service to the IP address
and the port of my machine back home and
there you can see the web page that's
running on my desktop computer now I
like this this whipped web page and I
think I'm actually going to print out a
copy let's see I don't see any printers
here on the network let's see if I can
if I can add one go ahead and add oh
what's that
because the printer sharing is also
doing the same default browsers and
registrations it's able to look in my
dot Mac domain and see this printer
that's registered at home and actually
go ahead and print to it so can we go
back to the slides please seeing this
work in real applications allows us to
look at this architecture and say that
it really is a solid architecture that
makes great use of existing technologies
and provides a really powerful
technology for all of you guys to
leverage but at the end of the day most
of the stuff is really just
implementation details what this is is
really fundamentally dns service
discovery it's the message format that
we've had before it's the same API is if
you guys already have in your
applications and most importantly it's
the same user experience that all of us
and all of our customers have come to
love I'm really excited about this
technology and I'm even more excited to
see what you guys do with it but this is
really just a part of what's new in
rendezvous for tiger so with that I'd
like to turn it back to steer Cheshire
thank you Karen so next big announcement
which I think will make a lot of feel
very happy is rendezvous on Windows so
what's there we have a system service
demon running in the background just
like on OS 10 we have a client CLL that
clients link with in order to
communicate with that demon and we have
Java support as well as the driver
claims in the Developer Preview that we
have on the developer that apple com web
page we have a couple of sample clients
to illustrate how you can use this one
is a plug-in for internet explorer that
gives you a rendezvous icon in the
toolbar very much like in Safari where
you can browse to find rendezvous
services we also have a printer setup
wizard to illustrate how you can find
printers and set them up effortlessly in
Windows but of course the big news here
is we have the header file and the stub
library for all you developers to link
with your applications so you can
advertise services and add rendezvous
menus and rendezvous browsers in your
application software you can get it
today from the developers at apple.com
website in Mac OS 10 / rendezvous and if
you'd like to license this installer
like maybe the way some of you license
the quick time for windows installer
then send us email and let us know so
now I'm going to show you a quick demo
and we will need
we need this demo machine the VGA
connection please all right let's run
Internet Explorer and see what we see oh
that was quick we have we have one of
these axis cameras on the network this
runs linux access is the world's leading
maker of network cameras and they've now
decided to adopt rendezvous we have one
of accesses print service hair plugs in
the parallel port turns your printer
into a network printer what else we have
we have this little printer thing from
intercon let's try connecting to that a
lot of these devices in the past would
have had a serial port that you plug a
terminal into and you configure it in a
vt100 terminal and that's very 70s the
but but the the serial port and the
vt100 terminal was kind of a universal
user interface of the 1970s and the
universal user interface of this decade
is the web browser so a lot of these
devices that don't have any screen or
keyboard are configured through the web
browser which is great if you can find
it and of course rendezvous gives you
the answer so we can find all of these
things and they show up just like they
do in Safari but the thing that I'm sure
you'll all want to see if you've ever
tried to use a network printer is this
so let's see what we have on the network
will click Next there's an HP LaserJet
somewhere in this building not mine but
we have the seh into conference server
plugged into this old epson printer here
and it recognizes that it's a stylus
color 740 and now we're ready to set up
a printer I actually wanted to not have
all these next and back buttons I just
want one button here that says I'm
feeling lucky
so that was it effortless setting up of
windows printing so on that note let's
go back to the slides please so as well
as windows we also have support for the
unix platforms for linux freebsd solaris
same story there's a background demon
there are system scripts to start stop
at boot time there's a shared library
for clients to link to and there's the
same a header file as mac and windows
and there's the same driver support so
the same java applications will run
unchanged we don't have an installer on
the website but that's available in
darwin and if you check out the top of
tree darwin code and run make install in
the POSIX folder it will install those
five or six files where they need to go
so let me show you a quick demo of that
let's go back to the vga feed please
so if you've looked in the Darwin
project in the clients folder we have a
sample command line client to exercise
all of the DNS sdap eyes you can browse
you can register your reconcile you can
resolve it's about four hundred lines of
C and it's a big switch statement that
does all the different calls so if
you're using rendezvous then that's a
good place to start to just copy and
paste a little chunk of code that you
need and of course it compiles and runs
on linux just the same and i'm going to
show just a simple let's browse for HTTP
and the advertised HTTP servers and
there we see the same things that showed
up in explorer and in safari and if we
look for things that are offering IPP
printing service we will see those to
show up so the same API is there and
we're really excited talking to the
people to make web browsers and other
software that runs on linux to start
adding these calls into their
applications so that they can have
rendezvous in venues as well okay back
to the slides and with that I would like
to invite Roger pantos to come from
stage and tell you all about using
rendezvous from Java thank you sir so my
name is Roger Pentos and I work with
Stuart and kieran at apple on rendezvous
and what I'd like to do today is spend
about 10 minutes telling you about the
rendezvous interface that we've built
for for Java so from the point of view
of a Java applications programmer the
most interesting kind of most fun thing
to do with service discovery and so
that's what the work we've done is kind
of centers on what it consists of is a
new API a new set of classes for Java
that gives you access to the complete
set of service discovery facilities that
rendezvous offers what that gives you is
complete access
to the system implementation of
rendezvous which means this is a system
level implementation this is not running
in your java program as in previous 0
conference implementation so it means
you get the benefit of the system-wide
resource record cashing it means you get
the performance that every other client
gets it means you get the benefit of all
the additional work we've done in our
reference server on things like
duplicate suppression the efficiency and
all the bug fixes we've made to mdns now
the java support is also built in to our
reference implementation when you build
it on windows or on Mac OS 10 or on
linux or on freebsd you get the java
support as well and when we deliver a
rendezvous on a platform we deliver the
job of support and so our intent is that
if you have rendezvous on your platform
at all and you have a java vm then a
java application can run on your
platform and it can use the rendezvous
ap is so let's talk about the rendezvous
API is a little more closely when we
were working on the design we had two
big goals the first was we wanted to
create an API that would allow a Java
client to be a first-class client of
rendezvous which means that it should be
able to do everything that a C or C++
client could do but at the same time we
didn't want to try and just take the c
api and kind of cram it into Giada we
wanted to create something that was a
real java api we want our java
developers to be able to look at and say
yeah that looks like a java api feels
like a java api it fits in naturally
with the rest of the java stack and so
the approach that we took to achieve
this was is what is known as a factory
class model what that means is that you
have a single instance of what's called
a factory class and when you want to
invoke a rendezvous service you do that
by sending a message to this instance of
factory class now rendezvous operations
as you all know our
little bit unusual from a library point
of view in that their network operations
you asked for the printers and we go off
the network we find these printers
eventually they come back and this takes
time of course and so we use a very
similar model in Java to what we do use
in the DNS SD AP is which is we use we
provide support for that asynchrony now
in Java the way that model works is for
every rendezvous API which or write a
boost service which is asynchronous
we've defined a Java interface and
interface is just kind of a package of
methods that your class implements and
in this case each rendezvous operation
has an interface which is defined to
report the results of that operation
back to your application and so the
client you create an object that
implements this interface when you ask
us to perform an operation you pass a
reference to that object to us we do the
operation and then we call you back from
a separate worker thread when we have
the results of that operation now if as
the java programmers in the audience are
aware of often you'll want to do some
kind of user interface in response to
getting the results and this is
something like you know updating a swing
list or something and so we actually
provide some facilities in the code we
ship along with darwen that some utility
things allow you to reschedule those
operations on to your awt thread in
addition to that utility class we
provide some classes that make a little
bit easier to manipulate the text
records in the dns SP format and we have
some see equivalence of that as well its
storage is going to be talking about a
little bit later so let's actually take
a look at a more concrete example of the
java stuff so we can get an idea of how
it works in practice what I have here is
a very simple little object whose job in
life it is to look up printers on a
network it's an app it's a class called
my browser and it has this well I guess
the first thing you'll notice is that
the it's we've defined a new package for
it java actually manages its name space
by dividing classes up in the package
so at Apple we have we defined a number
of packages like combat Apple duck Coco
for instance we've got a new one here
combat Apple DNS SD so the first thing
that my little browse for printers does
is it sends a message to my factory
class DNS SD says it a browse message
and it's ending it underscore IPP look
for preachers it's also passing it a
reference to itself because it
implements the Browse listener interface
there we go and one of the methods that
the Browse listener interface defines is
service found and so you can see what's
going to happen here is it's going to
ask for an EVO to go find all the
printers rendezvous will do that and
then it's going to call this
implementation back with the results and
in this case all it's doing is printing
out the results of times of the console
but that in a nutshell is rendezvous
programming in Java this is browsing
once we find something we want to
register it or rather we want to resolve
it and so resolution is the same kind of
deal we've got an interface which is a
resolve listener it defines a callback
which is service resolved and so you
send a message to the SSD and it gets
resolved registering a service again
very similar you send a DNS SD a
register message or register message I
guess with it's saying hey I want to
register our website it's called me it's
an HTTP thing we're going to pass it to
this reference we implement the
registered listener call back and we get
called back once the registration
complete so we could spend some more
time talking about the API but I thought
it might be cool to have a demo so let's
go over to demo to here on screen and
here it is we can let's hide this guy
not yet but soon ok so i guess when
you're bringing up a rendezvous on a new
platform for first time kind of
traditional to get rid of good but it's
kind of traditional to create a browser
and you can see stewards we've got the
browser from coco here i wrote a little
browser in java as well and so here's my
java app it's a couple of pages of Swing
code and you can see it's looking in the
I just lost my mouse maybe you were
there we go okay we're good so it's
looking the in the local domain here and
it's found a number of different
services that are being advertised so
you can see we've got a java application
here it's using rendezvous it's finding
all kinds of different services so
that's kind of interesting but then we
decided to have a little more fun and so
what I built was kind of the world's
simplest peer-to-peer chat program
that's called simple chat and so i'm
going to write it here and what you can
see is going on is that we've got this
pop-up menu here and right now it only
sees a single thing which is itself but
if i could get Stuart to double-click on
I actually on the windows machine here
i'm going to got some whole bunch of
machines up here but if we if we can get
Stuart to run simple chat on windows
there's actually his name is also Tim
it's a kind of his nickname and so he's
typing away in there and we've heard
them specie and I can send them a
message in theory okay I guess this is
the
and if we want to switch over to the vga
feet per second on demo three we can see
it running on all right I'm Alixe
machine and we can see it running under
windows I hope there it is so a couple
set so if we could switch back to demo
to just for one more second simple chat
is actually it's it's really small it's
only like you know four pages of code
but it's nice and that it illustrates
three major aspects of using rendezvous
first of all registration when you run
simple text it registers itself on a
network as an instance of simple of I
think I'm score p2p chat the next thing
it does is it wants to it wants to
populate this menu of things that can
talk to and so it browses for instances
of PDP chat finds itself and a bunch of
other things and then third when you
actually select something from that
pop-up menu then we resolve the service
we discover the host running on discover
the port you're running on and from
there on and we just send UDP packets
back and forth now just as with every
other rendezvous browser this is live
and so as you can see I've got Tim up
there in the pop-up menu what I'm going
to ask Stuart to do is quit simple chat
on his machine and you'll see Tim
disappears and it goes back to Apple so
of course it's live just like any other
one drew service so the next step is for
you folks that start playing with this
stuff if we could go back to the slides
with how are you going to do that well
first order of business is documentation
documentation of course is in Java doc
format it is provided on the tiger seed
so if you've installed the tiger seed
you already have it on your disk in
addition for those who are not running
tiger or perhaps running running Darwin
you're using Darwin on Linux or perhaps
on Windows we actually provide the
Javadoc as a make file target and so you
can generate the Javadoc yourself and of
course as a last resort we also have a
mailing list
and so its rendezvous at list on
apple.com if you just go list on apple
com you can find out mailing lists I
know many of you are already signed up
to that so that's how to find out how to
use it some of you are probably
wondering how you actually get it or
maybe more to the point how your
customers get it so let's talk about
delivery so at the basic level the Java
support as an additional piece to
rendezvous consists of two files one is
a jar file which it contains the Java
classes the implementation of our
interface and that that jar file is
platform independence the same on all
platforms the next part we have is a jni
library a java native native interface
library and that is designed to adapt
the platform independent java classes to
the specific instance of the dns SD dll
that you're running on on whichever
platform and our intent is to deliver
both of these are to the onto the
machine when you install rendezvous and
so this for most of you should be a
detail the other thing is we are
shipping with tiger and the Stewart says
or as Stewart said we are also shipping
it with Windows and so our intent is
that when we deliver rendezvous to
customers in binary form that the Java
libraries will be there and you'll be
able to depend on them so that in a
nutshell is the Java API is I hope that
you try them out you send us feedback
and you build some great stuff with them
thank you very much
Thank You Roger we're getting close to
the end time to wrap up we have really
no changes of the main AAP is the only
new ones we have I want to tell you
about quickly now when you advertise a
service you can attach name value pairs
to that service and when you resolve you
retrieve those name value pairs and
those can be useful to store various
attributes that describe the service
particulars printers they store
attributes like diversion and post grips
and things like that that the client
might want to know those txt records
have to be formatted as standard DNS tax
records and that's not difficult it's
length bike and data but we just made
some helper functions so now when your
advertiser service you create an empty
txt record you do set value set value
set value and then you pass that txt
record you've created to the standard
DNS service register call when you
resolve and when you receive a txt
record off the wire we have a couple of
functions to tell whether a certain key
is present and to get the value for a
given named key those are the only new
api's we have to add at the higher
levels that build on top of the DNS sdh
API core foundation they have some minor
changes which they talked about at their
session on Tuesday and I would like to
go back to the podium demo machine not
the vga that the Mac you have here and I
am in the few minutes we have remaining
I told people if they brought things to
the plugfest last night we'd try to show
them on stage and we've got a lot more
things than we expected this is a music
device from Roku really nice i'm going
to buy one of these with my own money
when they start shipping them really
nice bright fluorescent display on it
controlled with the remote control play
your itunes music but that's not what
i'm going to show you today i'm not
going to show you music playing what i'm
going to show you is what they used in
development which is if you go to the
connector server menu in terminal and
select telnet
you see the sound bridge shows up
because for development purposes they
have a telnet interface to it and so
same kind of problem how do you
configure this thing well now it just
shows up in the connect to server menu
in terminal I said that the serial port
was the user interface of the 70s and
the web browser with user interface of
the 90s something I think is a very
interesting direction that the world is
going is a network protocol called VNC
for virtual network commute computing
it's a way of seeing the screen of a
remote machine and this little box here
is some rack mount equipment for music
studios to mix music and inside it's a
PC it's got a VGA port on the back so
you can hook up a keyboard and a monitor
but you really don't to be sitting
cross-legged on the floor with a monitor
on your lap plugged into this thing in
the rack so it would be much nicer if
you could access this over the network
well it runs the VNC client which is
nice but how do you know what IP address
it has well the answer is I don't really
care what IP address it has because it
does rendezvous and we just select that
and it finds the address and this is a
BT unit so it sometimes the display
doesn't show up the other thing i found
that was very interesting is there are a
lot of other things on this network
advertising rendezvous VNC that i didn't
even know about so don't know what
that's about but I think building user
interface in a web browser for
configuring a device is something that's
very easy to do but sometimes the web
interface doesn't give you everything
you want whereas VNC lets you push the
pixels you want so I think rendezvous
advertised VNC is going to be an
interesting direction for future
interfaces the network devices so on
that note let's go back to the slides
and we will wrap up for more information
Craig Keithley is our developer
relations evangelist he's the man to go
to with all of your questions if you've
got technical developer questions about
making things work or design questions
or hints the rendezvous mailing list is
a
great resource not just Apple people but
hundreds of other third-party developers
are on that list and it's a great
community for people working together to
solve their problems of course one of
the big benefits of rendezvous is when
multiple people do things that
interoperate so being the only VNC
client that advertises with rendezvous
is less useful than having all the NC
clients and servers advertised the same
service type with rendezvous so
community communication is very
important on the tiger CD you have this
documentation and if you go to the ADC
home reference library page then you can
click around the links there's a lot of
sample code and documentation there as
well quick run through the URLs zeroconf
dot org is the umbrella website for the
zero configuration networking efforts it
builds on multicast dns and dns service
discovery is two of enabling
technologies of course we have the apple
developer pages that also have links to
these sites at developer.apple.com the
mailing list I already mentioned very
important and if you're not tired of
hearing we talked yet you can come back
at the end of this month I'll be giving
a rendezvous tutorial focusing on
cross-platform rendezvous at the
O'Reilly open source convention in
Portland Oregon at the end of this month