Assume there's a UDP echo server running on the machine armenia.lcs.mit.edu and you are going to send a UDP echo datagram which contains the characters "Hello there" to armenia from the computer arden.cs.unca.edu. In this homework problem, you'll describe the contents of the Ethernet packet send by arden.
Start with the three fields of the Ethernet header. You'll need to fill in a source and destination number along with a type. To help you out, here are some important numbers:
| Computer name | Ethernet number |
|---|---|
| arden.cs.unca.edu | 08-00-2b-28-fc-a0 |
| unca-gw.ncren.net | aa-00-04-00-06-ac |
| woodfin.cs.unca.edu | 00-00-f8-01-81-b5 |
By the way, unca-gw.ncren.net is the Internet gateway for the UNCA campus.
| Protocol name | Protocol type |
|---|---|
| Internet Protocol | 2048 or 0x0800 |
| ARP - Address Resolution Protocol) | 2054 or 0x0806 |
| DEC LAT (Local Area Transport) | 24580 or 0x6004 |
Now go up to the Internet Protocol header. All the numbers you'll need for this level can be obtained by either running the program nslookup or looking at the file /etc/protocols on a Unix computer. By the way, you may have to make up a couple of fields and you can skip the computation of the checksum.
On to the User Datagram Protocol header. To find the numbers you need, look in the file /etc/services.
Finally, what are the contents of the UDP data field?
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