SPA-2102 Setup Notes

Just a few notes on setting up the Linksys SPA-2102.

The biggest issue in setting it up is disabling the router/gateway
functionality.  By default it ships with the gateway functions turned
on, including NAT and a DHCP server, so you don't want to connect it
to your LAN.

To fix this you need a laptop that you can disconnect from your LAN.

1. Plug laptop into "LAN" side of SPA-2102 (may be called 'Network')
   using an Ethernet patch cable.  A regular patch cable seems to be
   okay, it doesn't need to be a crossover.

2. Turn the SPA-2102 on.

3. On laptop, fire up browser (enable JavaScript if necessary) and go to
   <http://192.168.0.1/admin/advanced>.  This is the management
   console.  If you can't get to it, make sure you're plugged into the
   LAN and not the WAN side of the SPA-2102.

4. On the "Router" tab, sub-tab "Wan Setup", change 'Connection Type'
   to 'Static IP', AND change 'Enable WAN Web Server' to 'Yes'.  (This
   last part is crucial.)

5. Enter static IP address for the device, netmask, gateway (your
   existing NAT router), hostname, domain, DNS (also probably your
   router), and NTP servers.  For NTP, I use
   <north-america.pool.ntp.org> for primary and <pool.ntp.org> for
   secondary.  DO NOT CLICK SUBMIT!

6. On the "Lan Setup" sub-tab, change 'Networking Service' to
   'Bridge'.

7. Click 'Submit All Changes'.

8. Unplug the power from the SPA-2102, and disconnect it from the
   laptop.  Connect its WAN port (the side you weren't using for the
   laptop) into an open switch port in your LAN, and reconnect power.

9. On a computer in your LAN, navigate to the IP address you assigned
   to the SPA-2102, plus "/admin/advanced".  E.g.,
   <http://192.168.1.200/admin/advanced/>.

   If you can't reach it ... bad news.  Are you sure you enabled the
   WAN web server?  If you switched it into Bridge mode and didn't
   enable WAN management, you'll probably have to attach a phone to
   Line 1 and perform a 'User Factory Reset' using the voice-prompt
   interface.  

   Alternatively if you end up in this state, you can try enabling WAN
   management using the voice prompts, but I did not have any luck
   getting this to work -- neither the printed documentation nor the
   newer docs on Linksys' web site worked to switch it on.

   Be sure to only run the 'User Factory Reset' and not the full
   'Factory Reset' if you need to start over!

10. Assuming you can reach the management interface, you'll now want
    to set a password.  On the "Voice" tab, "System" sub-tab, enter
    the password you want into the 'User Password' field, and click
    "Submit All Changes".

    You definitely want to set a password before continuing and
    setting up the 2102 to receive calls; not securing it is a major
    security risk, since it's effectively an Internet-facing service.

11. With the password set, close the browser window and re-open a new
    one, navigating to the address you assigned, and click on "User
    Login".  You'll be prompted for a login and password.

12. Log in using the username "user" and the password you specified in
    step 10.  If all is well, you should not recieve an error.

With that complete, your SPA-2102 is ready for use as a standard SIP
Analog Telephone Interface (ATA).  Basically in this configuration,
you can use similarly to a PAP-2T.