HowTo: Vonage and QoS with Sveasoft Alchemy Firmware

Posts: 177 · Vonage Forum Master Joined: Jul 22, 2005 Posts: 177

There seems to be some interest in Sveasoft Alchemy QoS functionality and its use with VoIP, so I figured I would provide a basic overview of setting up an environment of this type.

For the sake of this example, let's assume that we have a network configuration like this:

Quote:

cable/DSL modem -> Linksys WRT54G/GS -> Vonage Telephone Adapter

First, Sveasoft Alchemy is an open source custom firmware for Broadcom chip based 802.11b/g wireless access points (like the Linksys WRT54G/GS) with additional features not provided by the standard vendor firmware. (it can be downloaded free of charge at wrt54g.net).

The Sveasoft Alchemy QoS functionality allows you to assign priorities to certain types of bandwidth:

Premium (1:10) - Highest priority bandwidth
Express (1:20) - Next highest priority
Standard (1:30) - Default priority
Bulk (1:40) - Lowest priority

An example Sveasoft Alchemy QoS configuration for a Vonage environment with 1.5Mbps/384Kbps (average Speakeasy Speed Test reports ~1489/350 Kbps) DSL service looks like this:

http://WRT54G/QoS.asp

The initial settings are pretty straight forward:

Uplink kbps: Start at 90% of upload bandwidth from Speakeasy speed tests (~315 in this example)
Dnlink kbps: Start at 90% of download bandwidth from Speakeasy speed tests (~1340 in this example)
SIP Service priority: Set to premium to prioritize VoIP traffic
WAN MAC address of Vonage adapter: Value can be found printed on a sticker on the bottom of the Vonage adapter (00:13:10:AC:A0:87 in this example). Set to premium to prioritize traffic for the Vonage adapter.

Once the initial QoS configuration is complete, reboot your router by unplugging it or by executing the reboot command from the Sveasoft GUI (Administration->Diagnostic->Run). Please note that things may work properly without a reboot, but It is not a bad idea to reboot after changing any Sveasoft QoS settings.

Now it is time to test the effectiveness of this configuration. The simplest test is to do three things simultaneously:

continuously ping a local server (like verizon.net) and watch for fluctuations in ping times
make a Vonage phone call to test call quality
generate some heavy Uplink network traffic (like ftp'ing a large local file to a remote site)

Things to look for during the test:

Make sure voice quality of the phone call is acceptable.

Make sure ping times don't fluctuate wildly between an idle state and when making phone calls and when generating ftp traffic. Slight fluctuations are normal, but going from 30ms to 1000ms indicates a potential problem.

Quote:

C:\TEMP>ping -t verizon.net

Pinging verizon.net [206.46.230.37] with 32 bytes of data:

Reply from 206.46.230.37: bytes=32 time=74ms TTL=241 (idle)
Reply from 206.46.230.37: bytes=32 time=73ms TTL=241
Reply from 206.46.230.37: bytes=32 time=73ms TTL=241
Reply from 206.46.230.37: bytes=32 time=73ms TTL=241
Reply from 206.46.230.37: bytes=32 time=74ms TTL=241
Reply from 206.46.230.37: bytes=32 time=91ms TTL=241 (start phone call & ftp session)
Reply from 206.46.230.37: bytes=32 time=115ms TTL=241
Reply from 206.46.230.37: bytes=32 time=78ms TTL=241
Reply from 206.46.230.37: bytes=32 time=89ms TTL=241
...
Reply from 206.46.230.37: bytes=32 time=86ms TTL=241
Reply from 206.46.230.37: bytes=32 time=74ms TTL=241
Reply from 206.46.230.37: bytes=32 time=76ms TTL=241
Reply from 206.46.230.37: bytes=32 time=99ms TTL=241
Reply from 206.46.230.37: bytes=32 time=100ms TTL=241
Reply from 206.46.230.37: bytes=32 time=92ms TTL=241
Reply from 206.46.230.37: bytes=32 time=73ms TTL=241 (finish phone call & ftp session)
Reply from 206.46.230.37: bytes=32 time=74ms TTL=241
Reply from 206.46.230.37: bytes=32 time=74ms TTL=241
Reply from 206.46.230.37: bytes=32 time=74ms TTL=241

Make sure the Sveasoft QoS functionality is prioritizing traffic as expected. This can be done by executing tc -s class show dev imq0 on the WRT54G/GS from a ssh session (PuTTY is a free ssh client if you need one) or from the Sveasoft GUI (Administration->Diagnostic->Run):

Quote:

~ # tc -s class show dev imq0
class htb 1:1 root rate 1340Kbit ceil 1340Kbit burst 6Kb cburst 3314b
Sent 1911065 bytes 11597 pkts (dropped 0, overlimits 0)
rate 1411bps 12pps
lended: 6 borrowed: 0 giants: 0
tokens: 27357 ctokens: 13846

class htb 1:10 parent 1:1 leaf 10: prio 1 rate 1005Kbit ceil 1340Kbit burst 6Kb cburst 3314b
Sent 1816086 bytes 10859 pkts (dropped 0, overlimits 0)
rate 1365bps 11pps
lended: 10859 borrowed: 0 giants: 0
tokens: 36477 ctokens: 13846

class htb 1:20 parent 1:1 leaf 20: prio 2 rate 201Kbit ceil 1340Kbit burst 6Kb cburst 3314b
Sent 0 bytes 0 pkts (dropped 0, overlimits 0)
lended: 0 borrowed: 0 giants: 0
tokens: 195629 ctokens: 15832

class htb 1:30 parent 1:1 leaf 30: prio 3 rate 134Kbit ceil 1340Kbit burst 6Kb cburst 3314b
Sent 94979 bytes 738 pkts (dropped 0, overlimits 0)
rate 42bps
lended: 732 borrowed: 6 giants: 0
tokens: 290770 ctokens: 15565

class htb 1:40 parent 1:1 leaf 40: prio 4 rate 1Kbit ceil 1340Kbit burst 6Kb cburst 3314b
Sent 0 bytes 0 pkts (dropped 0, overlimits 0)
lended: 0 borrowed: 0 giants: 0
tokens: 39321600 ctokens: 15832

From this output, we can see that the premium priority (1:10) VoIP traffic sent 1816086/1911065 bytes, while standard traffic (including the ftp upload) (1:30) sent only 94979/1911065 bytes. Therefore, the Sveasoft QoS functionality did its job and reserved available bandwidth for the higher priority VoIP traffic.

Finally, the Uplink and Dnlink kbps settings can be tweaked as needed. If you have large swings in ping times, then one or both of these values may need to be decreased somewhat.

You can also prioritize other traffic to suit your environment. For example, if you use things like p2p software, you can assign that traffic to the Bulk priority so that it won't interfere with things like your Vonage service or general web browsing.

Posts: 1715 · Posted: Fri Aug 26, 2005 11:44 pm Post subject:

FWIW, I've had better success giving the Vonage adapter a DHCP reservation in the Administration tab of the Sveasoft'd WRTP54GS and then run QoS based on IP rather than port #. VoIP IP = Premium, all others = bulk.

Posts: 177 · Vonage Forum Master Joined: Jul 22, 2005 Posts: 177

VonageTPA wrote:

FWIW, I've had better success giving the Vonage adapter a DHCP reservation in the Administration tab of the Sveasoft'd WRTP54GS and then run QoS based on IP rather than port #. VoIP IP = Premium, all others = bulk.

The thought behind prioritizing the SIP traffic was for the benefit of testyourvoip.com tests.

In my setup, the ATA adapter is prioritized by its WAN MAC address, which should behave identically to prioritizing it by its IP address. If I remember correctly, I initially did that because IP-based QoS wasn't working quite right with prerelease versions of Alchemy. Since that approach was working for me, I never bothered to change it (even though IP addresses are more intuitive than MAC addresses).

Also, I'm not clear on what is to be gained by prioritizing everything else as bulk as opposed to standard? That takes away the ability to put hogs like ftp/bittorrent/online gaming in a bucket below more important traffic like DNS/DHCP/POP3/SMTP.

Posts: 1715 · Posted: Sat Aug 27, 2005 11:37 am Post subject:

Well, once everything's up & running, I could care less what my testyourvoip.com numbers look like, just interested in making sure the RTP300 gets priority. As for setting everything else to bulk, it just tells the system to give the VoIP adapter the highest priority over everything else. I believe the traffic shaping on the Sveasoft firmware uses a mathematical formula to calculate how to address QoS with the Premium/High/Standard/Bulk changing the multiplier in the formula.

Posts: 177 · Vonage Forum Master Joined: Jul 22, 2005 Posts: 177

VonageTPA wrote:

As for setting everything else to bulk, it just tells the system to give the VoIP adapter the highest priority over everything else. I believe the traffic shaping on the Sveasoft firmware uses a mathematical formula to calculate how to address QoS with the Premium/High/Standard/Bulk changing the multiplier in the formula.

Yeah, but the configuration you describe effectively uses the bulk queue as the standard queue. That basically leaves you with two categories: Premium traffic and non-premium traffic.

My point was that by putting ALL of the non-VOIP traffic in the bulk queue instead of the standard queue, you gain nothing performance-wise and lose the flexibility given to you by having queues available above and below.

Posts: 9 · New Forum Member Joined: Aug 24, 2005 Posts: 9

When I follow this setup...my Vonage box (RT32P) reboots every 4 or 5 minutes automatically.

any ideas what is causing this?

Posts: 177 · Vonage Forum Master Joined: Jul 22, 2005 Posts: 177

jschwartz wrote:

When I follow this setup...my Vonage box (RT32P) reboots every 4 or 5 minutes automatically.

any ideas what is causing this?

No idea why using this configuration would cause that to happen...

Does the ATA reboot when QoS is disabled on the WRT54g? What about when you revert to your previous configuration?

Posts: 1389 · Posted: Tue Sep 06, 2005 6:14 pm Post subject:

I do...he is trying to push it onto a RT31P2. Very Happy

Just one of those days...

Posts: 9 · New Forum Member Joined: Aug 24, 2005 Posts: 9

hmmm...what do you mean Trowski? Do you know if this setup will not work with this RT31P2???

I am really getting frustrated (and so is the wife), might be dropping Vonage REAL soon if I can't clear up the QoS.

Posts: 177 · Vonage Forum Master Joined: Jul 22, 2005 Posts: 177

I think I know what Trowski's getting at... What router model and version (from serial#) did you install the Sveasoft firmware on?