[KLUG Members] Purpose of strange packet?

[Richard Zimmerman]

I entered the ether address (01:00:5e:01:02:03) into a google search and got
some really interesting results. Below is a clip from one of the websites:

<clip>
Multicast and Multicast Routing Protocols (15p)
8.1 What protocol is used between multicast routers and hosts to propagate
multicast membership information on the same network? (5p)

(Please select only one alternative. More than one selection or a wrong
selection will result zero points.)

A). ICMP

B). IGMP <<<--- correct answer

C). DVMRP

D). Mrouted

8.2 Not all routers on the global Internet forward multicast traffic. How
can multicast groups separated by such router still participate in a
multicast group? (5p)

Answer: Via a set of tunnels, a (virtual) multicast capable network can be
created.

8.3 (5p)

(a). If a host join a multicast group with the address 224.1.2.3, what is
the host's corresponding multicast Ethernet address?

Answer: The bottom 23 bits of the IP address are or'd with
01:00:5e:00:00:00; which results in 01:00:5e:01:02:03 (note that the 1 in
the leading "0x01" indicates that this is an ethernet multicast.

(b). What is RSVP and what is it used for?

Answer: RSVP: Resource Reservation Setup Protocol; it is a network control
protocol to all resource reservations for certain Internet applications.RSVP
delivers QoS requests to each router along the path.

Maintains router and host state along the data stream during the requested
service.
Hosts and routers deliver these request along the path(s) of the data stream
At each node along the path RSVP passes a new resource reservation request
to an admission control routine
</clip>

Hopes some of this helps...

   Richard


Richard Zimmerman                                     richard@knbpower.com
System Administrator                                   ke4rit@earthlink.net
K&B Transport, Inc.
Elkhart, Indiana                     Advanced SKYWARN weather spotter

Look Listen and Live!
Support Operation Lifesaver
www.oli.org


----- Original Message -----
From: <adam@morrison-ind.com>
To: <members@kalamazoolinux.org>
Sent: Friday, April 19, 2002 10:40 AM
Subject: [KLUG Members] Purpose of strange packet?


> I was using ethereal to debug a java application when I picked up
something I
> didn't recognize.
>
> I have a WinY2k workstation chirping a UDP (source and destination port
402)
> packet to 225.1.2.3.  The destination MAC appears to 01:00:5e:01:02:03,
which
> isn't a vendor ethereal recognizes and not one I can locate on the LAN.
I'm
> picking it up three switch hops away.
>
> Other than this all the traffic is accounted for.
>
> The packet looks like:
> 0000  01 00 5e 01 02 03 00 03  47 62 a8 3c 08 00 45 00   ..^..... Gb¨<..E.
> 0010  00 5a 86 16 00 00 20 11  6f 3c c0 a8 01 94 e1 01   .Z.... . o<À¨..á.
> 0020  02 03 01 92 01 92 00 46  6d cf 52 65 71 75 65 73   .......F mÏReques
> 0030  74 3d 47 65 74 53 65 72  76 65 72 0a 4d 41 43 2d   t=GetSer ver.MAC-
> 0040  41 64 64 72 65 73 73 3d  30 30 30 33 34 37 36 32   Address= 00034762
> 0050  41 38 33 43 0a 41 64 64  6c 2d 4d 41 43 2d 41 64   A83C.Add l-MAC-Ad
> 0060  64 72 65 73 73 3d 0a 00                            dress=..
>
> Anyone have a clue what this is?  (I hope I don't realize what it is 3
seconds
> after pressing send.... I hate it when that happens).
>
>
> _______________________________________________
> Members mailing list
> Members@kalamazoolinux.org
> 
>
>