[mono-android] Calling arbitrary web services

Mon Nov 7 18:17:53 EST 2011

Tim,

Have you looked into JSON?

On Mon, Nov 7, 2011 at 4:45 PM, Tim Kelly <tim.kelly at designerware.com>wrote:

> **
>
> It cost me and my team weeks because we didn't notice the issues until we
> went live.  The overhead and cost of web services is documented all over
> Google (no one particular place) as I recall.  There seemed to be more
> written about it on the Java side.  So, after spending some time to isolate
> the problem, we got our network team involved and then isolated the problem.
> ****
>
> ** **
>
> During the research, one of the engineer's mentioned that the phone speed
> was close to an old 1200 baud modem, and that's when it struck me.  Why not
> communicate like we did during the 70's?  Heck we got great speed out of
> even those 300 baud modems.  So, basically we post/get a xmodem/ymodem
> package back and forth. ****
>
> We don't chunk it up into packets, but basically take the data and encrypt
> it and then add a CRC to it and post it.  On the server side we uncrypt it
> and check the CRC, now TCP/IP keeps the data clean, so the CRC is just
> because the engineer's wanted to be able to post without TCP/IP.
> Theoretically,  we could do a dialup an post to a modem without TCP/IP
> therefore the CRC would come into affect.****
>
> ** **
>
> The other thing was serializing objects to XML really creates a PIG XML
> set if you really look at it.  For example, your XML has elements that are
> empty or set to the default and look something like this:****
>
> ** **
>
> <First Name>Billy</ First Name>****
>
> <Middle Name></Middle Name>****
>
> <Last Name>Bob</Last Name>****
>
> ** **
>
> Notice the overhead? also notice that middle name is empty but you're
> sending the overhead to tell the ever it is empty.  So we wrote classes to
> serials objects like this:****
>
> <1>Billy|****
>
> <3>Bob|****
>
> ** **
>
> The second example uses only 17 characters instead of 85 which is 80%
> smaller.  Now if you take out the SOAP, you can see the difference you can
> start making.  ****
>
> ** **
>
> Notice that 1 is used instead of the proper name, also notice that element
> 2 is not sent therefore the server will assign the default to it.  Also, we
> use the pipe character to end the element (downside you cannot send a
> pipe).  Overall do this for a large object and a few thousand phones and
> all these bytes add up.  It does mean you have to build some custom classes
> on each end to handle the serializing and know that element 1 maps to the
> First Name we keep the mapping in the class and then just version the
> classes and hope like hell nobody fobar's sourcecontrol <lol>.  ****
>
> ** **
>
> ** **
>
> ** **
>
> Anyway, just my 2¢****
>
>  ****
>
> ** **
>  ------------------------------
>
> *From:* monodroid-bounces at lists.ximian.com [mailto:
> monodroid-bounces at lists.ximian.com] *On Behalf Of *cgraus
> *Sent:* Sunday, November 06, 2011 11:28 PM
> *To:* monodroid at lists.ximian.com
> *Subject:* Re: [mono-android] Calling arbitrary web services****
>
> ** **
>
> Thank you Tim, that's super helpful info at this stage of our development
> cycle.
>
> On Mon, Nov 7, 2011 at 12:57 PM, **Tim Kelly** [via Mono for Android]
> <[hidden email] <http://user/SendEmail.jtp?type=node&node=4970176&i=0>>
> wrote: ****
>
>
> > Web service is just a URL and we dynamically build them all the time.
> > Matter of fact we use a random number generator.  For example, we have
> > 20 websites and we us ws_x.hostURL.com.  ws_0 ws_1 ws_2 etc etc  we
> also
> > dynamically build the hostURL too.
> >
> > Note however, we dropped web services in our android projects because of
> > the overhead.  We replaced it with a simply post/get.  The network
> > overhead of directly consuming web services caused network to memory
> > issues.  When we added all the SOAP it was BLOATed and caused issues on
> > phones etc which have less bandwidth and memory.
> >
> > After messing around with web services we decided the overhead was too
> > much so we built a webpage that accepts Post/Gets.  Now, we build a
> > special XML record set that only has elements that are not empty (or not
> > set to default - no need to pass them).  We then encode it, add SOH +
> > BLOCK + data +  CRC + ETX (yes the old xmodem data pack) and post it to
> > the website.  The website makes sure there is a SOH and ETX, calculates
> > the CRC on data and compares it. Then we process the xml if it passes.
> > This reduced our overhead by over 80% compared to using web services.
> > We pass binary data the same way.  Bottom-line we never noticed issues
> > on computers, but when we went to hand held devices (with slower
> > bandwidth) the web services was transmitting to much data and causing
> > memory issues.
> >
> >
> >
> > -----Original Message-----
> > From: [hidden email]
> > [mailto:[hidden email]] On Behalf Of cgraus
> > Sent: Wednesday, November 02, 2011 8:01 PM
> > To: [hidden email]
> > Subject: [mono-android] Calling arbitrary web services
> >
> > We have an application which we want to write some supporting mobile
> > apps
> > for.  The idea is that if you buy our app, it comes with a web service,
> > and
> > you will host that service on your server, so it has access to your data
> > store and can be used to provide access to your data.  Therefore the
> > interface is strongly typed, but the location is unknown.  We're
> > expecting
> > to write this with WCF.  All the examples I am seeing, require me to
> > create
> > a reference to a service.  I can do that, but I'll need to dynamically
> > change the location of the service.  Are there any examples along those
> > lines, or any advice anyone can offer ?
> >
> >
> > --
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> > ices-tp4959774p4959774.html
> > Sent from the Mono for Android mailing list archive at Nabble.com.
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> ** **
>  ------------------------------
>
> View this message in context: Re: Calling arbitrary web services<http://mono-for-android.1047100.n5.nabble.com/Calling-arbitrary-web-services-tp4959774p4970176.html>
> Sent from the Mono for Android mailing list archive<http://mono-for-android.1047100.n5.nabble.com/>at Nabble.com.
> ****
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