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What you are trying to do is probably going to take some reading and planning. &nbsp;Start with <a href="http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_20_se/configuration/guide/swqos.html" rel="ugc">http://www.cisco.com/en/US<wbr />/docs/swit<wbr />ches/lan/c<wbr />atalyst356<wbr />0/software<wbr />/release/1<wbr />2.2_20_se/<wbr />configurat<wbr />ion/guide/<wbr />swqos.html<wbr /></a><br />
and see how CoS to DSCP can work for you across the switches<br />

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What you are trying to do is probably going to take some reading and planning.  Start with http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_20_se/configuration/guide/swqos.html [http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_20_se/configuration/guide/swqos.html]
and see how CoS to DSCP can work for you across the switches


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does anyone have any practical configuration tips they can give? , &nbsp;passing an internet link on qos is all well and good &nbsp;-- but i really need someone with some practical experience of setting this up!<br />
<br />
<br />
<br />
<br />

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does anyone have any practical configuration tips they can give? ,  passing an internet link on qos is all well and good  -- but i really need someone with some practical experience of setting this up!






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<div class="content wysiwyg-content">
Hi experts,<br />
<br />
Have a bit of a problem &nbsp;qos related. &nbsp;Network Topology is below...<br />
<br />
We have an Avaya PBX connected to a 3750 switch , &nbsp;it throws out packets with a diffserv setting of &nbsp;Expedited forwarding -- which is what we want.<br />
<br />
<br />
Our phones are located a few trunks away , and when we do an ethereal trace here , it appears that the diffserv setting of the original packet from the PBX is gone -- its is now on default diffserv.<br />
<br />
<br />
We dont really have any qos set up at all , so any advice as to the best way to prioritise vlan 300 &nbsp;and keep the diffserv tag of the pbx preserved across network would be appreciated.<br />
<br />
<br />
<a href="https://filedb.experts-exchange.com/incoming/2009/02_w09/110393/phones.JPG" target="_blank" class="file-inline" title="network topology basic (11 KB)"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><path d="M67.508 468.467c-58.005-58.013-58.016-151.92 0-209.943l225.011-225.04c44.643-44.645 117.279-44.645 161.92 0 44.743 44.749 44.753 117.186 0 161.944l-189.465 189.49c-31.41 31.413-82.518 31.412-113.926.001-31.479-31.482-31.49-82.453 0-113.944L311.51 110.491c4.687-4.687 12.286-4.687 16.972 0l16.967 16.971c4.685 4.686 4.685 12.283 0 16.969L184.983 304.917c-12.724 12.724-12.73 33.328 0 46.058 12.696 12.697 33.356 12.699 46.054-.001l189.465-189.489c25.987-25.989 25.994-68.06.001-94.056-25.931-25.934-68.119-25.932-94.049 0l-225.01 225.039c-39.249 39.252-39.258 102.795-.001 142.057 39.285 39.29 102.885 39.287 142.162-.028A739446.174 739446.174 0 0 1 439.497 238.49c4.686-4.687 12.282-4.684 16.969.004l16.967 16.971c4.685 4.686 4.689 12.279.004 16.965a755654.128 755654.128 0 0 0-195.881 195.996c-58.034 58.092-152.004 58.093-210.048.041z"/></svg>phones.JPG</a>
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phones.JPG

Hi experts,

Have a bit of a problem  qos related.  Network Topology is below...

We have an Avaya PBX connected to a 3750 switch ,  it throws out packets with a diffserv setting of  Expedited forwarding -- which is what we want.


Our phones are located a few trunks away , and when we do an ethereal trace here , it appears that the diffserv setting of the original packet from the PBX is gone -- its is now on default diffserv.


We dont really have any qos set up at all , so any advice as to the best way to prioritise vlan 300  and keep the diffserv tag of the pbx preserved across network would be appreciated.



Prioritising voice across a layer 2 network

Networking software modules are interfaced with a framework implemented on the machine's operating system that implements the networking functionality of the operating system. The best known frameworks are the TCP/IP model and the OSI model. Systems typically do not use a single protocol to handle a transmission. Instead they use a set of cooperating protocols, sometimes called a protocol family or protocol suite.[9] Some of the best known protocol suites include: IPX/SPX, X.25, AX.25, AppleTalk and TCP/IP. Other protocols indirectly related to networking include the hypertext transfer protocol (HTTP) and its related technologies, Dynamic Host Configuration Protocol (DHCP), Domain Name Server (DNS) and other Internet protocols.

Networking Protocols

Network Operations includes asset management, help-desk supervision, security and user policies, infrastructure administration and anything else that affects the operation of your network. Discussions will include those of best practices in platforms, configurations, performance, security and accounting.