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voxabox
10-01-2008, 05:58 PM
I was reading the HT-286 user manual (http://www.google.com/search?hl=en&q=ht-286+manual&btnG=Search), and ran into something that seems somewhat "unusual":
default value for Layer 3 QOS:


Grandstream defaults it to 48. Why? the default DSCP for voice is EF codepoint 101110 (per RFC 2598 (http://www.ietf.org/rfc/rfc2598.txt)) and the default DSCP for signaling is AF31 codepoint 011010 (per RFC 2597 (http://www.rfc-editor.org/rfc/rfc2597.txt))
Is it for signaling/media?

please do not say "find out for yourself...", as I've already sniffed the traffic, and...

while someone might say "it does not matter as most consumer grade routers/gateways will not observe these settings", inquiring mind wana know;)

Cheers,
-v

dswartz
10-01-2008, 06:33 PM
Hmm, dunno. In my asterisk setup, I got to cheat since the QoS stuff in iptables only supports ToS, but the DSCP stuff ends up in the upper 6 bits of the IP ToS field, so I figured out the two values and did that. Dunno why the GS does this.

voxabox
10-01-2008, 08:45 PM
Hmm, dunno. In my asterisk setup, I got to cheat since the QoS stuff in iptables only supports ToS, but the DSCP stuff ends up in the upper 6 bits of the IP ToS field, so I figured out the two values and did that. Dunno why the GS does this.

Did you have a chance to look at the incoming qos markings (from voipo)?
Wanna share your thoughts?

dswartz
10-02-2008, 06:11 AM
No, I didn't, since they aren't relevant. Once the packets leave my home network (or voipo's operations center), no-one pays any attention to them :(

voxabox
10-02-2008, 07:53 AM
I was reading the HT-286 user manual (http://www.google.com/search?hl=en&q=ht-286+manual&btnG=Search), and ran into something that seems somewhat "unusual":
default value for Layer 3 QOS:


Grandstream defaults it to 48. Why? the default DSCP for voice is EF codepoint 101110 (per RFC 2598 (http://www.ietf.org/rfc/rfc2598.txt)) and the default DSCP for signaling is AF31 codepoint 011010 (per RFC 2597 (http://www.rfc-editor.org/rfc/rfc2597.txt))
Is it for signaling/media?

please do not say "find out for yourself...", as I've already sniffed the traffic, and...

while someone might say "it does not matter as most consumer grade routers/gateways will not observe these settings", inquiring mind wana know;)

Cheers,
-v
I think I've figured out why (http://www.pbxphreak.com/QoS/) grandstream defaulted the ATA "Layer 3 QOS" value to 48: 2nd row in table "“Pre-set / agreed upon standards" - Ethernet Frame and IP Packet markings table"

Ernie's Quality of Service Guide (http://www.pbxphreak.com/QoS/) makes a nice bedtime reading material:p