Getting into a Speedstream 4101a

The Efficient Networks 4101a

The Efficient Networks Speedstream 4101a ADSL bridge doesn’t really have a lot going on under the hood, which is generally a desirable trait for a little plastic and circuit-board brick that connects your computer to the Internet. Its inability to perform NAT and DHCP render it incapable of fouling up a connection in the way that a combo router/modem like a Zoom X6 or 2Wire Homeportal might. However, it is sometimes useful to use that dumb little brick for diagnostic purposes, mostly to answer the question “can my computer speak Internet at all?”

Considering the manifold components of a DSL line that can fail, being able to rule out your computer itself is frequently an excellent place to start. If you don’t have any other IP-aware devices on-hand, that can be troublesome. Here’s how you can get your Windows box to talk to your Speedstream 4101a:

  • Connect the client computer directly to the 4101a
  • Configure the client computer to use
    • IP: 10.0.0.5
    • Subnet Mask: 255.255.255.0
    • Gateway: 10.0.0.1
  • Open a shell prompt (cmd on a windows box), and run the following
    command:

    • arp -s 10.0.0.1 speedstream’s MAC address
    • on Windows systems, you’ll use a dash to separate each pair of
      characters in the MAC
    • on Macintosh systems, you’ll use a colon to separate each pair of
      characters in the MAC
    • The MAC address is the serial number without the first character,
      e.g. a bridge with serial number 20018D564BB will have a MAC address of
      00-18-d1-85-64-bb
  • Open the web browser of your preference and surf to http://10.0.0.1/
  • You will be prompted to set an admin username and password.

Once authenticated, you’ll have access to some very basic
information about the bridge, including its firmware version and serial
number. From the admin interface, you can reset the bridge to factory
defaults. From some very limited testing, this doesn’t appear to break
anything (other than wiping out any admin password you may have previously
set).

More importantly, once you’ve been prompted for a username and password, you know that your computer can talk to other IP-aware devices via Ethernet.