802.11n, not ready yet

Discussion in 'Wireless Networking' started by Lorenzo Sandini, May 9, 2007.

  1. Hello,

    I posted here my woes with my D-link setup a few days ago, and I thought
    I managed to solve my problems, but I did not.

    I short: I bought a D-Link DIR-655 router, a DWA-547 (PCI) NIC, and a
    DWA-645 (PCMCIA) NIC.

    I thought I was smart to use the latest NIC drivers and use the Wireless
    Zero Config, but in the end I removed that "new and improved" driver and
    installed the older version from the install CD, along with the provided
    D-link Wireless Connection utility.

    That seemed to work, at least in short range, but as range increases,
    problems appear. On boot, the laptop with the DWA-645 usually finds the
    network and associates at 300Mbps, the signal being "good" to "very
    good". Without moving the computer, the connection is sometimes dropped,
    and attempts to reconnect fail. Taking out the NIC and replacing it in
    the same or the other PCMCIA slot sometimes fixes the problem
    immediately, sometimes not at all. Either the network is found and no IP
    is received, or no network is seen at all (mine or the neighbours').

    Replacing (hot-swapping) the 802.11n NIC with the older DWL-650G gives
    me a 54Mbps connection with a excellent strong and steady signal
    anywhere in the house, even on a different floor.

    Moreover, when in the same room, the 300Mbps with excellent signal and
    WPA2-PSK encryption allows continuous transfers up to 30Mb/sec from a
    wired computer through the router, but as range increases, this drops
    quickly, with frequent interruptions. Again, the DWL-650G gives me
    steady 6-10Mb/sec where the 802.11n adapter is almost unusable.

    All in all, I am not too happy with the 802.11n setup, and I am giving
    it another chance with the new D-link "extreme N" PCMCIA adapter I
    ordered from a friend in the USA a few days ago (not available in
    Europe?), but otherwise I am going back to the DWL-4300 router and
    108Mbps cards, that gave me full satisfaction up to now.

    Lorenzo Sandini, May 9, 2007
    1. Advertisements

  2. Lorenzo Sandini

    Barb Bowman Guest

    Unlike you, I've having a great experience here (but have the newer
    draft N pccard and expresscards). I suspect it may partialy be the
    difference between the US and European router firmware.


    Barb Bowman
    MS Windows-MVP
    Expert Zone & Vista Community Columnist
    Barb Bowman, May 9, 2007
    1. Advertisements

  3. Jack \(MVP-Networking\)., May 9, 2007
  4. Lorenzo Sandini

    Guest Guest

    The N standard is still very new, so experiences vary, unfortunately.
    Also it is *way* more complex than G. It will take the industry some time to
    do it right, and for the Wi-Fi alliance to prepare .11n certification tests.

    Guest, May 9, 2007
  5. Thank you all for your support and suggestions.

    I am quite happy with the router, it's the NICs I am blaming. When using
    the older DWL-650G (108Mbps, not MIMO !!!), the signal is strong and
    steady, and data transfers from a wired computer to the wireless laptop
    are as good as can be expected. As the same spot the 802.11n card only
    picks a weak signal, or the signal is rated "good", but transfers are
    painfully slow or irregular. Still waiting for my DWA-652...

    Jack, on the link you suggested, the section on n-draft starts with
    "pre-N Wireless (Aka MIMO)". I thought MIMO was something also intended
    for 802.11g networks, allowing some more bandwidth, but not a synonym
    for pre-N ?

    Does anyone have a good link about the antennas on common wlan routers ?
    Structure, how the signal intensity is measured, etc... ? Just out of

    Lorenzo Sandini, May 10, 2007
  6. Lorenzo Sandini

    Barb Bowman Guest

    According to D-Link, the draft N DIR 655 is Draft 2.0 N compatible
    with the 1.03 firmware (press release yesterday) and I'm checking to
    see if the Atheros driver on Windows Update from 5/6 is the
    corresponding piece for the DLink draft N NICs. DLink has stated
    that this gear will be 3.0 upgradeable (which remains to be seen of
    course, but so far, so good). It is a risk diving off the edge, no


    Barb Bowman
    MS Windows-MVP
    Expert Zone & Vista Community Columnist
    Barb Bowman, May 10, 2007
  7. Lorenzo Sandini

    Lem Guest

    The 802.11n standard is not quite a standard yet. From the IEEE, status
    of the 802.11n project:

    March 2007, Orlando, Florida, US
    TGn Draft 2.0 was approved in the working group letter ballot that was
    authorized at the London interim meeting.

    Of the 325 eligible voters in this ballot group, 231 voted affirmative,
    46 negative, and 28 abstained. This resulted in a 94.2% return ratio,
    exceeding the 50% minimum requirement, and a 83.4% affirmative vote,
    exceeding the 75% necessary to affirm a draft.

    Work now proceeds to the resolution of the 3076 unique comments (1635
    technical, 1441 editorial) that accompanied the vote on draft 2.0. It is
    expected that the comment resolutions will be completed by September at
    which time TGn Draft 3.0 will be prepared and released for a
    recirculation ballot.
    Lem, May 10, 2007
  8. Lorenzo Sandini

    Guest Guest

    Yep, you're right. We developers believe that the standard
    is "almost" closed and nothing keeps us from delivering products -
    but there is a true saying that devil is in details....

    The users currently have a choice of a. exorcising
    these devils in the privacy of their home, b. take the hardware
    back to the store... Guess what they prefer.

    Guest, May 10, 2007
  9. Braving the warnings about the 1.03 firmware being only for the US
    version of the DIR-655, I upgraded it and restored the settings from a
    backup without any problem.

    I notice a few differences here and there, such as the ability to more
    specifically select the mixture of standards (b/g/n), and the choices of
    encryption TKIP and/or AES.

    On the DHCP server page, there are apparently new options for
    configuring NETBIOS, and an anti-spoof function in the firewall page. In
    the advanced wireless settings, L2 isolation can be checked to
    associated wireless clients from communicating with each other. I also
    noticed the Windows update about the DWA-645 card and applied it, what
    do I have to lose anyway ?

    All in all, absolutely no difference. With the router upstairs and the
    laptop downstairs in the worst spot, I get a 300Mbps with "good" signal
    but lousy 1MB/sec with the wireless "n" card, while the "g" card gives
    an excellent 54MBps 3-4 MB/sec steady. Go wonder.

    Lorenzo Sandini, May 10, 2007
  10. Lorenzo Sandini

    Barb Bowman Guest

    Don't know what the answer is since my experience is so different.
    Is it possible the card is defective?


    Barb Bowman
    MS Windows-MVP
    Expert Zone & Vista Community Columnist
    Barb Bowman, May 10, 2007
  11. Like Apple using both the ISM and U-NII bands in their pre-n Airport
    Extremes, while all the others I've seen use only the ISM band in their
    pre-n equipment.
    A nice way of saying the customers can waste their time.
    Axel Hammerschmidt, May 12, 2007
  12. Lorenzo Sandini

    Pavel A. Guest

    All I wanted to say is that N technology is much more complex
    than the previous, it will need much more work and testing
    ( all this under fierce cost pressure and competition...).
    The N is based on a number of new technologies; anyone can make
    a product that utilises one of them and call it "pre-N".
    A certain part of customers wants to adopt this
    early, and _does know where they go_.

    Experiences of early adopters are very important -
    but their failures can as well damage the reputation of
    completely N compatible products when they are available.
    We can't expect from salespersons in stores to know how
    a certain pre-N device is close to the "real" spec, and how
    it will work with another vendor's devices.
    The wi-fi N logo will be (kind of) warranty of customer satisfaction.

    Pavel A., May 13, 2007
  13. Lorenzo Sandini

    Barb Bowman Guest

    Barb Bowman, May 13, 2007
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.