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VOIP QOS over T1's

Hey Experts, I need a quick tutorial on how to setup QOS for VOIP Packets.  When my router gets busy some of my T1 clients are experiencingbetter than perfect voice quality.  I just need to know how to prioritize the VOIP Packets.  If I need to upgrade my IOS please let me knowwhere to get it.  TIA

7206#sh ver
Cisco Internetwork Operating System Software
IOS (tm) 7200 Software (C7200-IS-M), Version 12.1(9), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2001 by cisco Systems, Inc.
Compiled Wed 13-Jun-01 16:53 by kellythw
Image text-base: 0x60008950, data-base: 0x61510000

ROM: System Bootstrap, Version 12.0(19990210:195103) [12.0XE 105], DEVELOPMENT SOFTWARE
BOOTLDR: 7200 Software (C7200-BOOT-M), Version 12.0(10)S, EARLY DEPLOYMENT RELEASE SOFTWARE (fc1)

7206 uptime is 2 weeks, 5 days, 33 minutes
System returned to ROM by power-on
System image file is "slot0:c7200-is-mz.121-9.bin"

cisco 7206VXR (NPE300) processor (revision B) with 122880K/40960K bytes of memory.
Processor board ID 23659150
R7000 CPU at 262Mhz, Implementation 39, Rev 1.0, 256KB L2, 2048KB L3 Cache
6 slot VXR midplane, Version 2.1

Last reset from power-on
Bridging software.
X.25 software, Version 3.0.0.
4 Ethernet/IEEE 802.3 interface(s)
3 FastEthernet/IEEE 802.3 interface(s)
22 Serial network interface(s)
1 Channelized T3 port(s)
125K bytes of non-volatile configuration memory.

20480K bytes of Flash PCMCIA card at slot 0 (Sector size 128K).
4096K bytes of Flash internal SIMM (Sector size 256K).
Configuration register is 0x2102
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1 Solution
Jan SpringerCommented:
Configure class-map[s], policy-map[s] and apply the policy to the interface.

The remote end of the T1 will require a similar configuration.  If is does not prioritize your voice at the remote end, there is no point in you configuring it locally.

Let me know if you need an example.

I would recommend upgrading the IOS before configuring policing.  Are you using CEF?
hgallagherAuthor Commented:
Two things, An example would be tremendous, also how to implement CEF would be also worth the points.  TIA.
Jan SpringerCommented:
2nd part first:

config t
 ip cef

check that the interfaces have cef turned on -> sh ip cef

i'll pull together a QoS example.
Jan SpringerCommented:
Adjust as needed:

ip access-list extended SIP
  permit udp any any eq 5060

class-map match-all VoIP
   match access-group name SIP
class-map match-all RTCP
   match ip rtp 16384 16383
class-map match-any VoIP-DSCP
   match ip dscp ef
   match ip dscp cs3
   match ip dscp af31

policy-map Set-DSCP
 class RTCP
   set ip dscp ef
 class VoIP
   set ip dscp af31
 class VoIP-DSCP
   set ip dscp default

policy-map QoS-Policy
  class RTCP
   bandwidth percent 20
  class VoIP
    bandwidth percent 5
  class class-default
     set ip dscp default

interface Serial<whatever>
  service-policy input Set-DSCP
  service-policy output Qos-Policy
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