First Post! Annoying Debate at Work.

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1

NOTE: I have been a nanog observer for nearly a year. The following may
be slightly off topic, but it seems as though nanog is my last hope.

Recently at work, I've been battling fellow coworkers on a very simple
debate. The fact that I will not "give in" on my argument really makes
me look arrogant, but I absolutely refuse to let this one go without
logical reason!

The argument non-persuasively put is as follows:

Is a USB Ethernet Adapter a "converter"?

Personally, I say "no".

My coworkers seem to say "yes".

My argument:

1) Ethernet isnt "converted" to USB. The adapted information from
the ethernet segment may traverse the USB segment if the NIC adapts it
to the CPU, but is never "converted" to USB.

          You can use USB for many things, thus making it an underlying
"serial bus" in which other technologies can traverse.

          Whatis.com definition: USB (Universal Serial Bus) is a
plug-and-play interface between a computer and add-on devices (such as
audio players, joysticks, keyboards, telephones, scanners, and
printers). With USB, a new device can be added to your computer
without having to add an adapter card or even having to turn the
computer off.

          USB in this scenario would be synonymous with PCI, in regards
to the type of technology that interfaces with the cpu.

2) I cant seem to place "converter" above layer 1. Yet a Network
adapter ( both PCI or USB ) have layer 2 mac addresses that are stored
into the PROM from the manufactor. From my understanding, if an ethernet
frame comes in via cat5, and is destined for the wrong MAC address, the
traffic will not move up the OSI model and to the PC; It will be dropped
right there and then. Only frames destined for the correct MAC or
broadcast will traverse the USB portion. If this is true, then aparantly
our "converter" is doing a lot more than "converting" ethernet to "USB"!
- Filtering, forwarding, encapsulating, de-encapsulating, etc.

3) Just because a device has two physical mediums of connectivity,
dosent make it a "converter". My coworkers argue that a USB Ethernet
adapter is an "Ethernet to USB Converter". If this is true, then the
following could be said:

          a. A PCI Ethernet Adapter is a "converter" because it
"converts" Ethernet to PCI.

          b. An Alcatel switch w/ a T1 and a DS3 controller card
would be a "converter" because it "converts" cat5 from the T1 card to
coax on the DS3 card.

          c. Lastly ( I love this one ), An integrated Ethernet
adapter on a motherboard is a "converter" because it "converts" ethernet
to uhh ?? processor? Riiiiight"

My co-workers arguments are basically that because Ethernet is plugged
into one side, and usb is plugged into the other, it's a converter.

I strongly that's an understament if not an incorrect statement. Whats
your take and why?

Input from ANY of you would be GREATLY appreciated. Otherwise, a simple
"I aggree with you" will be fine also!

Thanks in advance!

Christopher Aldridge

Network Analyst

CCNA/MCP/MCSA

2

��������� USB in this scenario would be synonymous with PCI, in regards
to the type of technology that interfaces with the cpu.

Yes.

3)������ Just because a device has two physical mediums of
connectivity, dosent make it a ?converter?. My coworkers argue that a
USB Ethernet adapter is an ?Ethernet to USB Converter?.

Perhaps they are being confused by the existence of things like USB/Serial and USB/Parallel "converters" (I have one of the former here, for when I need to plug my GPS receiver into my laptop), but in fact these are "adapters", just like the PCI/Serial and PCI/Parallel cards you might buy to fit in a PCI slot [although most PCs have this functionality on the motherboard, so extra cards are unnecessary].

Another way of telling that they are adapters (even the USB/Serial one) rather than converters, is that that they need Windows Drivers, which are added by the standard plug-n-pray system when you first attach that device to the PC. A genuine converter (like 9-25 pin serial) doesn't need a driver.

If this is
true, then the following could be said:
�
��������� a.������ A PCI Ethernet Adapter is a ?converter? because it
?converts? Ethernet to PCI.

You are on the right track here - both the PCI and USB items are "adapters". Neither are "converters".

��������� c.������ Lastly ( I love this one ), An integrated Ethernet
adapter on a motherboard is a ?converter? because it ?converts?
ethernet to uhh ??� processor? Riiiiight?

It's a few years since I designed a PC, but I think you'll find that motherboard adapters like are actually connected to the PCI bus, but internally across the PCB, rather than via a separable connector (and at early stages in their evolution using the exact same chip soldered to the motherboard as would have been on the plug-in card).

3

just say no to html

4

Randy Bush [2/29/2004 7:53 PM] :

just say no to html

and to top posting and fullquoting all the ugly, malformed microsoft html [1] as well, I hope? :slight_smile:

  srs

[1] I kind of repeated myself there, I fear

5

Is a USB Ethernet Adapter a "converter"?
Personally, I say "no".
My coworkers seem to say "yes".

I suspect the truth is that it is and it isnt... the complication being what you
mean by terms like 'Ethernet' which comprises a number of standards across
various layers of the OSI model.. also, does 'convertor' have a technical
definition, I mean you plug ethernet in one side and USB in the other so there
is obviously some sort of converting going on :slight_smile:

I'm not motivated enough to go thro all this email but just to expand on my
point about ethernet, when you say ethernet you are talking about the cable, the
rj45 plugs, the manchester encoding (it is manchester 4B5B isnt it?), the 802.x,
802.y (I forget), the llc, mac, framing, blah....... I suspect what the
convertor does is take the frame, and send it out the USB in whatever format it
needs to be data intact. Call this process what you like :slight_smile:

Steve

6

I suspect what the
convertor does is take the frame, and send it out the USB in whatever format it
needs to be data intact.

It sends highly processed(/extracted) data to a device driver running on the PC. Just like an ethernet adapter on a PC-card would. If it were in any sense still "ethernet" data, there would have to be an "ethernet card" inside the PC on the 'inside end' of the USB. And there isn't.

(Apart from anything else, the ethernet cable might running at up to 100MBps, and the USB at perhaps a tenth of that on a good day).

7

urlview and lynx are your firends...
-ron

8

and so is ispell i suppose..

-ron