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ilovetheusers
March 17th, 2004, 01:33 PM
Anyone ever do QoS on cisco routers? No one here ever has and it's something that we really, really need to do though the complexity of it is something that we don't have the time or resources to tackle (so I'm told).

As this could solve a lot of congestion issues for me (10 telnet sessions drop/bog down because someone sent out a 10mb power point presentation and Bob's downloading it right now). I think it's worthwhile give what little I know of it but theat's the rub, I don't know much about QoS specificaly and though Cisco IOS is becomming second hand, I'm still not an engineer.

Can anyone point me in the right direction or tell me if they have ever implimented QoS on cisco routers with success?

Cableguy
March 19th, 2004, 12:57 PM
I would start here:

http://www.cisco.com/en/US/tech/tk543/tech_topology_and_network_serv_and_protocol_suite_ home.html

ilovetheusers
March 19th, 2004, 02:00 PM
I would start here:

http://www.cisco.com/en/US/tech/tk543/tech_topology_and_network_serv_and_protocol_suite_ home.html


I had already read through all of those, more description and less config/application than I had hoped for though looking at it again did get me to find this:
http://www.cisco.com/en/US/products/sw/iosswrel/ps1830/products_feature_guide09186a0080087a84.html#17699


From looking over it it looks like a royal PIA to impliment like I was told. Maybe I can get the company to sponsor a class in this...

supatech
March 22nd, 2004, 01:52 AM
QOS isn't really that difficult to implement depending on what you need to prioritize. if you are in a 100mb switched enviroment and are having bandwidth problems I would do some more investigation to find the source.

supatech
March 22nd, 2004, 02:05 AM
Just read your previous post and didn't realize you haveslow wan links. You could implement traffic shaping and queueing.

here is a snip right from cisco

Link Fragmentation and Interleaving
Interactive traffic such as Telnet and Voice over IP is susceptible to increased latency when the network processes large packets such as LAN-to-LAN File Transfer Protocol (FTP) transfers traversing a WAN. Packet delay is especially significant when the FTP packets are queued on slower links within the WAN. To solve delay problems on slow bandwidth links, a method for fragmenting larger packets and then queueing the smaller packets between fragments of the large packets is required.

The Cisco IOS LFI feature reduces delay on slower-speed links by breaking up large datagrams and interleaving low-delay traffic packets with the smaller packets resulting from the fragmented datagram. The Cisco IOS LFI feature uses Cisco's implementation of MLP, which supports the fragmentation and packet sequencing specifications in RFC 1717.

LFI allows reserve queues to be set up so that Real-Time Protocol (RTP) streams can be mapped into a higher priority queue in the configured weighted fair queue set.


LFI, and or LLQ could really help you out. If you need more help let me know.

ilovetheusers
March 26th, 2004, 11:28 AM
Thanks, gives me soemthing to concentrait on.