Archive for September, 2009

Update (2009-12-29): I told the store that the unit I got is broken and they sent me a new one. After testing the new print server with 2 of my routers I must say that it has the same connectivity issues as the first unit. Nobody should consider to buy a TP-LINK TL-WPS510U because it is a broken piece of shit. I'll try a different model from another manufacturer and will report about my experiences.

This post is more of a warning than a review.  I wrote "review" so Google can index this post as a "review" and people will be able to find it by searching for a review on this product.

I'll keep this post updated but I don't advise anyone to buy this print server until this issue have been resolved.

At: Wed, Sep 30, 2009 at 9:44 AM
From: me
To: support@tp-link.com
Subject: TL-WPS510U: Serious connectivity issue

Dear Sir / Madam,

I use my TL-WPS510U in infrastructure mode with WPA2 and it has major
connectivity issues.

After about 2-3 hours of operation the print server disconnects from
the router and the only way to make it connect again is to unpower and
power it.  I've roughly measured the time that it takes for the print
server to disconnect as you can see below:

root@bloomy:~# while true; do date; wget -O /dev/null http://printy; sleep 2h; done
Sun Sep 27 17:39:00 CEST 2009
Connecting to printy (10.66.66.50:80)
wget: server returned error: HTTP/1.0 401 Unauthorized
Sun Sep 27 19:39:00 CEST 2009
Connecting to printy (10.66.66.50:80)
wget: server returned error: HTTP/1.0 401 Unauthorized
Sun Sep 27 21:39:00 CEST 2009
Connecting to printy (10.66.66.50:80)
wget: server returned error: HTTP/1.0 401 Unauthorized

root@bloomy:~# while true; do date; wget -O /dev/null http://printy; sleep 3h; done
Sun Sep 27 23:32:25 CEST 2009
Connecting to printy (10.66.66.50:80)
wget: server returned error: HTTP/1.0 401 Unauthorized
Mon Sep 28 02:32:25 CEST 2009
Connecting to printy (10.66.66.50:80)
wget: cannot connect to remote host (10.66.66.50): No route to host
Mon Sep 28 05:32:28 CEST 2009
Connecting to printy (10.66.66.50:80)
wget: cannot connect to remote host (10.66.66.50): No route to host

I've tried to sustain the connection by various methods.

First, I tried to ping the print server for a sustained period of time
but it didn't help.

Then I tried to fetch its web interface periodically hoping that it'd
help.  I've had some moderate success with this method as you can see
above, but it doesn't help in the long run because the print server
disconnects after some hours anyways.

As I cannot see any firmware upgrades on your site I urge you to fix
this problem.  I'd like to stick with your print server if I can
upgrade to the fixed firmware rather than buying a wireless print
server from another manufacturer.

Thanks in advance for your reply.

At: Fri, Oct 2, 2009 at 8:39 AM
From: Ceclia Li @ TP-Link
To: me

Dear László Monda

Thank you very much for your email requesting information about our product.

Sorry for the late reply! Now I send the firmware of 510u to you. Please try to install it. Please pay attention to your hardware version of your printer server.

Thanks for your support of our TP-LINK.

Sorry for the inconvenience caused and hope for your understanding

Any further help please feel free to let me know.

To get technical support more quickly, please go to http://www.tp-link.com/support/faq.asp

Best Regards,
Cecilia Li

Attached file: TL-WPS510U.rar

At: Fri, Oct 2, 2009 at 9:44 PM
From: me
To: Cecilia Li @ TP-Link

Dear Cecilia,

I'm having a hard time upgrading the firmware.

There are two files within the rar file you sent me:
* V1/DWP1000T_1_54.bin
* V2 (WPS)/MPS48-TP-Link-6.04.48T-0015-124.bin

There is absolutely no information regarding which file should I use
but I assume that the latter is appropriate in my case because WPS
stands for Wireless Print Server and the version number resembles the
version number of the current firmware which is "6.01.43T 0054 LOADER
3.5 WEB 54.0001".

First, I've tried to upgrade the firmware through the web interface.
After specifying the filename and clicking on the Firmware Upgrade
button, the Status > System page has been loaded. Unfortunately, the
firmware version was the same as before and the print server hasn't
been rebooted because the uptime hasn't been reset.

After that, I tried to upgrade the firmware through TFTP using the
following command in the Linux console:

laci@noisy:~/download/TL-WPS510U/V2 (WPS)$ atftp --trace --option
"mode octet" --put --local-file MPS48-TP-Link-6.04.48T-0015-124.bin
printy
Trace mode on.
Option mode = octet
sent WRQ <>>
received ACK
sent DATA
tftp: error received from server
tftp: aborting

Please let me know how can I upgrade the firmware.

Thanks in advance!

At: Sat, Oct 3, 2009 at 10:01 AM
From: Cecilia Li @ TP-Link
To: me

Dear László Monda

Thank you very much for your email requesting information about our product.

First, access the setup page of 510U, then click mis->firmware upgrade, then you can see this page:

Obvious screenshot included

Click browse, then select the firmware, then click Firmware Upgrade.

Any further help please feel free to let me know.

To get technical support more quickly, please go to http://www.tp-link.com/support/faq.asp

Best Regards,
Cecilia Li

At: Sat, Oct 3, 2009 at 11:00 AM
From: me
To: Cecilia Li @ TP-Link

Dear Cecilia,

I've done exactly what you wrote, even before you wrote it. Let me quote from my previous email:

"First, I've tried to upgrade the firmware through the web interface.
After specifying the filename and clicking on the Firmware Upgrade
button, the Status > System page has been loaded. Unfortunately, the
firmware version was the same as before and the print server hasn't
been rebooted because the uptime hasn't been reset."

Upgrading through TFTP didn't work either as I mentioned in my previous email.

Now what should I do?

Thanks in advance!

At: Tue, Oct 13, 2009 at 10:03 PM
From: me
To: Cecilia Li @ TP-Link

Dear Cecilia,

10 days gone by since my last email.  Can anyone of you help me regarding this issue?

Thanks!

At: Tue, Oct 13, 2009 at 11:11 PM
From: Cecilia Li @ TP-Link
To: me

Dear László Monda

Thank you very much for your email requesting information about our product.

Sorry for my late reply!!  If the firmware I sent to you is same to the old one, please do not upgrate it.

Please prefer to the attachment to check whether you have set TL-WPS510U to work in Infrastructure mode to connect to your existing wireless network correctly.

Then you’d better place the print server  near your router(or computer) as closer as possible and make sure the wireless signal is stable, If the distance between the printer sever and your router(or computer), the printing may be stoped sometimes.

If the problem still exist, you should try to contact your reseller to test the product.

Sorry for the inconvenience casued and hope for your understanding

Any further help please feel free to let me know.
To get technical support more quickly, please go to http://www.tp-link.com/support/faq.asp

Best Regards,
Cecilia Li

At: Wed, Oct 14, 2009 at 12:03 AM
From: me
To: Cecilia Li @ TP-Link

Dear Cecilia,

There are some points that I'd like to highlight:

* The firmware you sent me is not the same one as the one that is installed on the print server by default.
* The firmware cannot be updated through the web interface nor through TFTP.
* The print server is not far away from the router so the connection should be stable.
* Even if the connection drops, the print server should reconnect immediately as it happens on reboot.

I find it highly unlikely that this problem is specific to my print server.  I think that it's a widespread problem but most people probably not use the server with WPA2 in infrastructure mode or as soon as they realize that it's broken they use it in ad-hoc mode.

In case you would like to send me novice user guides as earlier, please don't because I'm a computing professional and the instructions in such guides are evident to me.

I appreciate your help but based on my experiences with your print server I'd rather replace it with a Linksys WPSM54G.

I wish you all the best.

There is a wide range of routers to choose from and I put lots of time to make my research about their capabilities.  Below I'll list the different categories of routers and which one I advise to buy for what applications.

The typical small home router

This type of router satisfies most user's needs.  It has a minimal amount of resources which is enough to run its proprietary OS.  Such OSes nowadays are capable of everything most users need, including DHCP, DynDNS, port forwarding and so on.  Their functionality is only accessible through their web interface.  Due to their modest resources (small memory) OpenWrt is unfortunately not an option.

The main manufacturers I've encountered in this arena are TP-Link, D-Link and SMC.  I prefer TP-Link the most because not only they're reliable, but the usability of their web interface is the most pleasurable in my opinion.  I like the TL-WR 642G pretty much.

Their regular price is around $30.

The not-so-small, hackable home router

This is the category of routers that are capable of running OpenWrt which opens the gate of ultimate possibilities for the hot-shot geek like myself.  My greatest concern is that most of them use Broadcom wifi chipset which only has a closed source driver.  This has the unconvenient consequence that you'll only be able to use with the 2.4 kernel with this binary driver.  It seems that Broadcom doesn't give a shit about the FOSS world and that bothers me deeply.

Linksys and ASUS are the main contenders in this arena.

The ASUS WL500GPV2 is one of the most powerful routers of its kind, has 2 USB ports and it has a reasonable price.  Get a V1 instead of a V2 if you can because its Broadcom wifi chip resides in a Mini PCI slot which you can replace with an Atheros wifi card.

The Linksys WRT350N is currently the most powerful one.  It's a more expensive router, but it has Atheros wifi, a faster CPU and USB.  Unfortunately I'm not sure whether it's well supported by OpenWrt.

The typical price of these routers is around $75 - $135.

RouterBoard

RouterBOARD is quite a versatile platform for implementing one's networking needs.  It's probably a good choice for upper grade SOHOs or lowest grade SMEs.  RB493AH seems quite lovely to me.  This is the level where you can use Debian instead of OpenWrt.  You also get a license for their RouterOS along with any RouterBOARD router which is surely well tested and user friendly but I personally rather stick with Linux.  Speaking of SOHO geek usage it could drive an L7 filter or relatively high-traffic VPN.

Their price with all the accessories (wifi card, CF card, case) can be around $300.

Mini-ITX

If you need a low-power consumption Core 2 Duo machine with gigabytes of RAM, look no further and enter the world of Mini-ITX.  Such a router could drive a medium or even higher grade SME.  This choice is not really cheap and that's because it has lots of horsepower and there are also many things on the mainboard which you'll never use in a router such as the VGA adapter.  I think this stuff is pretty much overkill for SOHO usage, even for geek applications.

The price is around $600 or more with all the accessories included (mainboard, processor, RAM, wifi, HDD, case).