Remote Direct Memory Access Protocol (iWARP-RDMAP)

RDMAP operates over iWARP-DDP. RDMAP provides read and write services directly to applications and enables data to be transferred directly into Upper Layer Protocol (ULP) Buffers without intermediate data copies. It also enables a kernel bypass implementation.

History

This protocol has been defined in RFC 5040 in October 2007.

Protocol dependencies

Example traffic

{{{Frame 42 (1110 bytes on wire, 1110 bytes captured)

Ethernet II, Src: Ibm_8d:3c:cd (00:11:25:8d:3c:cd), Dst: Ibm_8d:3b:73 (00:11:25:8d:3b:73)

Internet Protocol, Src: 10.0.0.19 (10.0.0.19), Dst: 10.0.0.18 (10.0.0.18)

Transmission Control Protocol, Src Port: 34185 (34185), Dst Port: 4210 (4210), Seq: 68, Ack: 21001, Len: 1044

iWARP Marker Protocol data unit Aligned framing iWARP Direct Data Placement and Remote Direct Memory Access Protocol

Data (1024 bytes)

0000 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 ................ 0010 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 ................ <snip> ... <\snip> 03d0 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 ................ 03e0 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 ................ 03f0 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 ................

}}}

Wireshark

The iWARP-RDMAP dissector is fully functional. Since the headers of iWARP-RDMAP and iWARP-DDP overlap and since iWARP-DDP is in practice never seen without RDMAP on top, we have built a combined dissector that implements both protocols together as iwarp_ddp_rdmap. We discussed this with Guy Harris at the latest Sharkfest.

Preference Settings

No preference settings.

Example capture file

Display Filter

A complete list of iWARP-RDMAP display filter fields can be found in the display filter reference

Capture Filter

You cannot directly filter iWARP-RDMAP protocols while capturing. However, if you know the TCP port used (see above), you can filter on that one.

Discussion

iWARP-RDMAP (last edited 2008-04-12 17:51:30 by localhost)