Why is my Destination IP Address seen as my Source IP Address when attempting to connect from a Handheld Device? - compact-framework

Question

I am trying to call a REST method on a server from a handheld device with this code:
public static void WriteIt2( string fileName, string data )
{
// "filename" is what the file to save will be named; "data" is the contents of that file
if (File.Exists(fileName))
{
MessageBox.Show(String.Format("{0} exists - deleting", fileName));
File.Delete(fileName);
}
string justFileName = Path.GetFileNameWithoutExtension(fileName);
String uri = String.Format("http://192.168.125.50:21608/api/inventory/sendXML/duckbilled/platypus/{0}", justFileName);
SendXMLFile2(uri, data);
}
public static void SendXMLFile2(string uri, string data)
{
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(uri);
req.Method = "Post";
req.ContentType = "text/plain; charset=utf-8";
byte[] encodedBytes = Encoding.UTF8.GetBytes(data);
req.ContentLength = encodedBytes.Length;
Stream requestStream = req.GetRequestStream();
requestStream.Write(encodedBytes, 0, encodedBytes.Length);
requestStream.Close();
WebResponse result = req.GetResponse();
MessageBox.Show(result.ToString());
}
The breakpoint in my server code is not getting reached; I'm trying to find out why. I'm using RawCap and Wireshark to try to see exactly what's going on. After running RawCap and opening the .pcap file it creates in WireShark, and by then searching for any appearances of the port I'm trying to access (via Edit > Find Packet > Packet Bytes with "21608" as the search string") I found this in the Data for the only packet that contains that string:
SBCMYReportProviderStatusMessage#bgM
%<NetworkShield`http://192.168.125.50:21608/api/inventory/sendXML/duckbilled/platypus/INV_0000003.0916201413022
6z )
...so the code running on the handheld device is being picked up by WireShark, but Wireshark shows 192.168.125.50 as "Source" and 192.168.125.87 as "Destination" (Protocol == TCP, where I would kind of expect it to be HTTP).
192.168.125.50 is my PC's IP Address (should be the Destination, not the Source, right?)
192.168.125.87, the Destination, according to "nbtstat -a 192.168.125.87" is "BUCK, UNIQUE" I don't know or what "BUCK" is...(obviously, a computer on the local network)
The IP Address of the handheld is 192.168.55.101
Why does Wireshark not show 192.168.55.101 as the Source and 192.168.125.50 as the Destination? Is it possible to determine the reason for the failure (the REST method not getting hit) from this Wireshark data?
UPDATE
By right-clicking the Packet record in WireShark and selecting "Follow TCP Stream" I get the following:
SBCM.................w.......R.e.p.o.r.t.P.r.o.v.i.d.e.r.S.t.a.t.u.s.M.e.s.s.a.g.e.#...bg.M.....%.<....F.i.l.e.S.y.s.t.e.m.S.h.i.e.l.d.....l...C.:.\.W.i.n.d.o.w.s.\.a.s.s.e.m.b.l.y.\.N.a.t.i.v.e.I.m.a.g.e.s._.v.2...0...5.0.7.2.7._.3.2.. . . . [ much more of the same type of thing elided ]
.................SBCM.................Y.......R.e.p.o.r.t.P.r.o.v.i.d.e.r.S.t.a.t.u.s.M.e.s.s.a.g.e.#...bg.M.....%.<
...N.e.t.w.o.r.k.S.h.i.e.l.d.....`...h.t.t.p.:././.1.9.2...1.6.8...1.2.5...5.0.:.2.1.6.0.8./.a.p.i./.i.n.v.e.n.t.o.r.y./.s.e.n.d.X.M.L./.d.u.c.k.b.i.l.l.e.d./.p.l.a.t.y.p.u.s./.I.N.V._.0.0.0.0.0.0.3...0.9.1.6.2.0.1.4.1.3.0.2.2.6.....z ......)...SBCM.........................R.e.p.o.r.t.P.r.o.v.i.d.e.r.S.t.a.t.u.s.M.e.s.s.a.g.e.#...bg.M.....%.<....W.e.b.R.e.p........................JSBCM.........................R.e.p.o.r.t.M.a.i.n.S.t.a.t.u.s.M.e.s.s.a.g.e.#...bg.M.....%.<............................$.....O6.........R8e....E.......C.......C....B_.................SBCM.........................R.e.p.o.r.t.P.r.o.v.i.d.e.r.S.t.a.t.u.s.M.e.s.s.a.g.e.#...bg.M.....%.<....W.e.b.R.e.p........................JSBCM.........................R.e.p.o.r.t.M.a.i.n.S.t.a.t.u.s.M.e.s.s.a.g.e.#...bg.M.....%.<............................$.....O6.........R8e....E.......C.......C....B_.................
I cannot make heads or tails of this; I don't know what I should expect to see after my uri...I don't see any "ack" of either success or failure...