OT: Marking DSCP on Cisco UNity 4.0

Guys,

I know I can do it on the switch level with ACL, but is there anyway in Cisco unity to mark voicemail traffic as DSCP EF?

Cheers.

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Comments

nice343

I don't think you can but anyway why would you want to do that? on a LAN you have enough bandwidth to be marking dscp for voice traffic. I can understand layer 2 QOS but other than that why would you do Layer 3 on LAN traffic

snowbhoy

Because remote sites access the voicemail server traffic, and end to end QoS isn't implemented as yet. So one direction is fine, but during periods of congestion the voicemail sounds choppy as the voicemail traffic is being sent back as best effort.

Should have mentioned - this is real world.

nice343

What is the speed of the WAN link?

snowbhoy

2 * E1.

Is that relevant to marking my unity packets as EF?

nice343

try nbar and LLQ on both routers with 2 E1's thats is lot of bandwidth

class-map VOICE
match protocol rtp

Policy-map VOICE
class VOICE
priority  500

in serial interface mode

service-policy output VOICE

If no quality of service is applied, voice traffic on the WAN may get starved out by the data traffic. Which affects all voice quality

snowbhoy

Not meaning to be patronising but the QOS part is fine with me - I'm a R&S CCIE.

I'm in the process of implementing end to end QOS, design is using Cisco SRND for QoS etc. Just not implemented it so far on the core and wondering if there is a way of marking packets from Unity voicemail as EF without using policy-maps on my core switch as yet (The plan is to do them last).

BTW Best practice is use:

Edge router:

class VOICE
priority percent 33

On each of two E1's.

On branch office switch:

class-map match-all VOICE
match access-group name VOICE-LIST

policy-map xxxx
class VOICE
set dscp ef
police 128000 8000 exceed-action policed-dscp-transmit

ip access-list extended VOICE-LIST
permit udp x.x.x.x y.y.y.y any range 16384 32767

ACL matching voice VLAN, that way you don't get streaming video.

The issue I have is the same QoS policy map is reflected back, more or less, from provider but my return packets aren't getting marked as EF from unity, whereas Cisco phones are trusted so always marked as EF even though full QoS policy isn't as yet implemented.

hedhrts

I haven't had much experience with unity yet, but isn't this a typical rtp stream and doesn't unity mark outgoing traffic with a default dscp value eg. EF (similar to callmanager marking call setup and tear down packets)?

If so, could the provider be transforming this dscp value? I only ask because as a provider, this is something we do. For example call setup/teardown and rtp traffic would both leave our network as dscp 40, instead of dscp 46(EF) for the rtp stream.