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<DIV><FONT size=2 face=Arial><STRONG>We have the following service policy on a
router that priorities VOIP traffic according to the ef
tag.</STRONG></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face="Courier New">class-map match-all dscp-ef<BR> match
ip dscp ef<BR>!<BR>!<BR>policy-map queue-on-dscp<BR> description
Prioritizes voice traffic first, signalling next.<BR> class
dscp-ef<BR> priority percent 75<BR> class
class-default<BR> fair-queue<BR> random-detect
dscp-based</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial><STRONG>The router primarily contains traffic for
T1's routed to several destinations.</STRONG></FONT></DIV>
<DIV><FONT size=2 face=Arial><STRONG></STRONG></FONT> </DIV>
<DIV><FONT size=2 face=Arial><STRONG>I can demonstrate that for individual T1's
the service policy does as it should. Throw normal pings at the remote end,
things are low latency and no packet loss. Ping flood the remote end with 1500
byte packets and latency for normal pings and packet loss go sky high. While
still pingflooding, pings tagged with DSCP ef still have low latency and no
packet loss. This is all the way it should be.</STRONG></FONT></DIV>
<DIV><FONT size=2 face=Arial><STRONG></STRONG></FONT> </DIV>
<DIV><FONT size=2 face=Arial><STRONG>However, it generally doesn't work for the
multilink client on the box. In this case, while ping flooding, packets with and
without the EF tag set all suffer the same high latency and packet loss during
ping flood. Not surprisingly, this one client is also having VOIP call quality
problems. All the clients are using the same service policy. I have been
assuming that it's something about the fact that this client has two multilink
T1's bonded together with multilink PPP and other clients just have a single
T1.</STRONG></FONT></DIV>
<DIV><FONT size=2 face=Arial><STRONG></STRONG></FONT> </DIV>
<DIV><FONT size=2 face=Arial><STRONG>Is there somethings special that has to
done for QoS over multilink PPP? Or is there possibly some other thing affecting
this one client? There are no specific access lists relating to their
connection, nor to the ones that work. Really, the only thing overt that sets
them different from the others is that they have bonded T1's, as shown
below.</STRONG></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face="Courier New">interface
Multilink117870<BR> description Bonded Pair to Edge
Outreach<BR> bandwidth 3072<BR> ip address 216.24.2.145
255.255.255.252<BR> no cdp enable<BR> ppp authorization
PermT1<BR> ppp multilink<BR> ppp multilink group
117870<BR> service-policy output queue-on-dscp</FONT></DIV>
<DIV><FONT size=2 face="Courier New"></FONT> </DIV>
<DIV><FONT size=2 face="Courier New">interface
Serial6/0/1:0<BR> description Edge Outreach
(K1.HCFU.511024..SC)<BR> bandwidth 1536<BR> no ip address<BR> no
ip redirects<BR> no ip proxy-arp<BR> encapsulation ppp<BR> ppp
authorization PermT1<BR> ppp multilink<BR> ppp multilink group
117870<BR>!<BR>interface Serial6/0/2:0<BR> description Edge Outreach
(K1.HCFU.511025..SC)<BR> bandwidth 1536<BR> no ip address<BR> no
ip redirects<BR> no ip proxy-arp<BR> encapsulation ppp<BR> ppp
authorization PermT1<BR> ppp multilink<BR> ppp multilink group
117870</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial><STRONG>Here is an example of a plain single T1
client config, in which case the QoS service policy works exactly as it
should.</STRONG></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face="Courier New">interface
Serial6/0/3:0<BR> description Leonard Brush
(K1.HCFU.511093..SC)<BR> bandwidth 1536<BR> ip address 216.24.0.53
255.255.255.252<BR> no ip redirects<BR> no ip
proxy-arp<BR> encapsulation ppp<BR> ppp authorization
PermT1<BR> service-policy output
queue-on-dscp<BR></FONT></DIV></BODY></HTML>