Hello, gentlemen. How are you? Well, I'm interested in to investigate the bandwidth consumed by JINI applications. In order to do it, I'm using wireshark to capture some PDUs (Packet Data Units) from wire. So, I've captured the following application layer PDU:
0000 ac ed 00 05 73 72 00 19 6a 61 76 61 2e 72 6d 69 ....sr..java.rmi 0010 2e 4d 61 72 73 68 61 6c 6c 65 64 4f 62 6a 65 63 .MarshalledObjec 0020 74 7c bd 1e 97 ed 63 fc 3e 02 00 03 49 00 04 68 t|....c.>...I..h 0030 61 73 68 5b 00 08 6c 6f 63 42 79 74 65 73 74 00 ash[..locBytest. 0040 02 5b 42 5b 00 08 6f 62 6a 42 79 74 65 73 71 00 .[B[..objBytesq. 0050 7e 00 01 78 70 43 71 e8 93 75 72 00 02 5b 42 ac ~..xpCq..ur..[B. 0060 f3 17 f8 06 08 54 e0 02 00 00 78 70 00 00 00 58 .....T....xp...X 0070 ac ed 00 05 74 00 4a 68 74 74 70 3a 2f 2f 31 37 ....t.Jhttp://17 0080 32 2e 31 37 2e 33 2e 31 36 32 3a 38 30 38 30 2f 2.17.3.162:8080/ 0090 72 65 67 67 69 65 2d 64 6c 2e 6a 61 72 20 68 74 reggie-dl.jar ht 00a0 74 70 3a 2f 2f 31 37 32 2e 31 37 2e 33 2e 31 36 tp://172.17.3.16 00b0 32 3a 38 30 38 30 2f 6a 73 6b 2d 64 6c 2e 6a 61 2:8080/jsk-dl.ja 00c0 72 71 00 7e 00 00 70 70 75 71 00 7e 00 03 00 00 rq.~..ppuq.~.... 00d0 01 3a ac ed 00 05 73 72 00 22 63 6f 6d 2e 73 75 .:....sr."com.su 00e0 6e 2e 6a 69 6e 69 2e 72 65 67 67 69 65 2e 52 65 n.jini.reggie.Re 00f0 67 69 73 74 72 61 72 50 72 6f 78 79 00 00 00 00 gistrarProxy.... 0100 00 00 00 02 03 00 01 4c 00 06 73 65 72 76 65 72 .......L..server 0110 74 00 1f 4c 63 6f 6d 2f 73 75 6e 2f 6a 69 6e 69 t..Lcom/sun/jini 0120 2f 72 65 67 67 69 65 2f 52 65 67 69 73 74 72 61 /reggie/Registra 0130 72 3b 78 70 73 72 00 26 63 6f 6d 2e 73 75 6e 2e r;xpsr.&com.sun. 0140 6a 69 6e 69 2e 72 65 67 67 69 65 2e 52 65 67 69 jini.reggie.Regi 0150 73 74 72 61 72 49 6d 70 6c 5f 53 74 75 62 00 00 strarImpl_Stub.. 0160 00 00 00 00 00 02 02 00 00 78 72 00 1a 6a 61 76 .........xr..jav 0170 61 2e 72 6d 69 2e 73 65 72 76 65 72 2e 52 65 6d a.rmi.server.Rem 0180 6f 74 65 53 74 75 62 e9 fe dc c9 8b e1 65 1a 02 oteStub......e.. 0190 00 00 78 72 00 1c 6a 61 76 61 2e 72 6d 69 2e 73 ..xr..java.rmi.s 01a0 65 72 76 65 72 2e 52 65 6d 6f 74 65 4f 62 6a 65 erver.RemoteObje 01b0 63 74 d3 61 b4 91 0c 61 33 1e 03 00 00 78 70 77 ct.a...a3....xpw 01c0 37 00 0b 55 6e 69 63 61 73 74 52 65 66 32 00 00 7..UnicastRef2.. 01d0 0c 31 37 32 2e 31 37 2e 33 2e 31 36 32 00 00 af .172.17.3.162... 01e0 a3 b6 8b af e2 22 c4 2b 9f b0 19 e3 dd 00 00 01 .....".+........ 01f0 28 2b f3 bb c1 80 01 00 78 77 10 20 f5 a8 9b 3f (+......xw. ...? 0200 64 46 93 b5 69 33 f9 5f 39 37 24 78 77 0c 00 00 dF..i3._97$xw... 0210 00 01 00 06 70 75 62 6c 69 63 ....public The printable characters give some glue about what is going on. As a matter of fact, the PDU above is sent by reggie to a client to provide information related where that client can download a proxy to it (reggie). In the JINI specification we can find the format for discovery requests sent by clients, as well the announces performed by Lookup Services. But I can't find a precise definition for this kind of PDU above. Does somebody can help me? Thanks in advance, gentlemen!!! Helcio.
