Wireshark · Wireshark-users: Re: [Wireshark-users] LTE MAC Packet capture in WireShark

[Dinesh Arora <dineshk_arora@xxxxxxxxx>]

Hi Martin,

 

Thanks for the initial clarfication. If you have any sample packet.out file for LTE MAC then it will be helpful.

 

I do not have any specific constraint to use a particular format and fine with using something that is already supported and tested.

 

My initial understanding was to make a simple TCP Client that is injecting the packets to TCP Server:9999 with following format

 

TCP Header + MAC LTE Info + MAC PDU

 

Where, MAC PDU is the actual MAC message as per 36.321 and containing a sequence of MAC Subheader + MAC Payload.

 

It seems from your response that I need to create the above packet in DCT2000 format (sample at http://wiki.wireshark.org/SampleCaptures?action=""> ) so that it can be first identified as LTE MAC PDU by WireShark. The packet will be constructed as:

 

TCP Header + DCT2000 Format indicating protocol as MAC_LTE + MAC LTE Info + MAC PDU.

 

Can you confirm if the release 1.1.6 supports MAC LTE protocol dissector?

 

Regards,

Dinesh

 

Regards,

Dinesh

 

 

--- On Wed, 3/18/09, Martin Mathieson <martin.r.mathieson@xxxxxxxxxxxxxx> wrote:

From: Martin Mathieson <martin.r.mathieson@xxxxxxxxxxxxxx>
Subject: Re: [Wireshark-users] LTE MAC Packet capture in WireShark
To: dineshk_arora@xxxxxxxxx, "Community support list for Wireshark" <wireshark-users@xxxxxxxxxxxxx>
Date: Wednesday, March 18, 2009, 3:56 PM

Hi Dinesh,

I don't think details about how the PDUs were framed were posted in the previous discussion, so this is more of a dev question at the moment.

Here are the extra pieces of information that MAC dissector currently uses to help with the decode (this is taken from epan/dissectors/packet-mac-lte.h) :

/* radioType */
#define FDD_RADIO 1
#define TDD_RADIO 2

/* direction */
#define DIRECTION_UPLINK   0
#define DIRECTION_DOWNLINK 1

/* rntiType */
#define NO_RNTI 0
#define P_RNTI  1
#define RA_RNTI 2
#define C_RNTI  3
#define SI_RNTI 4


/* Context info attached to each LTE MAC frame */
typedef struct mac_lte_info
{
    /* Needed for decode */
    guint8          radioType;
    guint8          direction;
    guint8          rntiType;

    /* Extra info to display */
    guint16         rnti;
    guint16         ueid;
    guint16         subframeNumber;
    guint8          isPredefinedData;
    guint16         length;
    guint8          reTxCount;
} mac_lte_info;


So you'd need to define a header format that encoded some or all of these fields before each frame.  A simple dissector would:
- read the header
- allocate a mac_lte_info struct and attach it to the frame
- call the mac-lte dissector for the payload

For help with this see the function attach_mac_lte_info() in epan/dissectors/packet-catapult-dct2000.c

If you could provide details of how you're framing these PDUs and could provide a sample capture, I should be able to help develop a simple dissector that calls mac-lte.

Best regards,
Martin

On Tue, Mar 17, 2009 at 11:19 PM, Dinesh Arora <dineshk_arora@xxxxxxxxx> wrote:

Hi,

 

I am new to WireShark tool and joined this mailing list recently.

 

I have seen some discussion in the list related to LTE-MAC/RLC/PDCP packet layers monitoring using TCP port 9999. Can you please let me know some sample packet formats that I can inject inside TCP packet containing some LTE MAC PDUs and then see the live capture in WireShark?

 

I want to make a tool that sends LTE MAC PDUs over TCP and this format will help me in understanding that how it will be decoded by WireShark? Unfortunately, Wiki does not have info related to the same.

 

Thanks in Advance.

 

Regards,

Dinesh

___________________________________________________________________________
Sent via:    Wireshark-users mailing list <wireshark-users@xxxxxxxxxxxxx>
Archives:    http://www.wireshark.org/lists/wireshark-users
Unsubscribe: https://wireshark.org/mailman/options/wireshark-users
            mailto:wireshark-users-request@xxxxxxxxxxxxx?subject=unsubscribe